Showing posts with label occlusion training. Show all posts
Showing posts with label occlusion training. Show all posts
Monday, May 3, 2010
Occlusion Training: Tightening up everything we don't know about Hypertrophy
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If we asked someone "what should i do to build muscle" probably not a lot of people would say "cut off the blood flow to a working limb." Turns out though, that this latter kind of work - called occlusion training, or blood flow restriction (BFR) - has proven a powerful technique for inducing hypertrophy at very low loads (10-30% of a 1RM). While it's mainly been explored as a rehab technique to help accelerate recovery, some researchers have been looking at it as an approach in regular training. What, then, are the pro's and con's of this technique for training? And what are we learning about the mystery that is hypertrophy from studying the phenomena of occlusion for hypertrohhy strength?
These questions are addressed in an excellent review of occlusion research from 2008 called " Ischemic strength training: a low-load alternative to heavy resistance exercise?"
Two of the highlights of the paper (at least for me) -the review of hypertrophy models such as they are and a possible rationale for the Pump in bodybuilding circles.
Overview on the (un)Known of Muscle Building
The authors go through an amazing job of investigating the known models of hypertrophy - and all that we dont know about it - to see where occlusion training may fit in with existing models. Heck, in order to understand what role occlusion plays, we need to have some sense of the depth and breadth of the puddle it's playing in.
Unaccustomed as i am to being brief, i'm actually not going to go through these models in detail here. Suffice it to say though that what we have often thought of as the biggie thing to boost in order to super charge hypertrophy may not hold. The authors do a lovely job of showing for instance that heh, post occlusion training, yes Growth Hormone (GH) is up and IGF-1 is up, but according to all this other research, we really don't know if the presence of these hormone levels is really what's upping protein synthesis at all.
Not just hormones, the reviewers look at other factors too - like mechano checmical. THat means that maybe the calcium involved in the actin/myosin bridge that enables contractions is a key to what's really important for hypertrophy - but so far there aren't studies looking at these responses in occlusion, so we have no comparison.
This review is great for myth busting. In other words, its review of what we can actually point to and say "that's what casues muscle growth" shows us what we know is so small, it's really exciting. Why is being able to say "but we don't know if that's what's doing it" exciting? One, it means we're starting to know what's going on in more detail to be able to say we don't know and two, it means in any discussion about somebody saying this is WHY this works (like why the pump "works") we can be pretty confident in knowing they maybe shouldn't be so confident.
It may seem a fine point, but work like this also lets us continue to say that "if you do this protocol, you'll get big" - assuming it's been tested on lots of athletes of various types. What we cannot say with the same confidence is WHY if we follow that protocol we're getting big.
I recommend the full first half of the article just for this review of the state of the art (as of 2008) on hypertrophy.
SO where does this get us then with occlusion and hypertrophy?
First a few words about occlusion training - what is it?
Occlusion training goes by a bunch of names: kaatsu training, occlusion, Blood Flow Restriction (BFR), ishemic training. Occlusion generally means to obstruct or block or even hide something (from view). In the case of muscle work, the blood flow is obstructed, usually by a tournequette of some kind. Ischemia is sort of the technical term for blood flow restriction - to the heart or other body tissue -as a result of some type of block (or occlusion).
Protocols - often seem to involve tournequetting the working limb, then using loads of 10-30% of a 1RM, usually lots of reps, very low rest, until fatigue hits. The results in strength gains are similar to working sets with 80% 1RMs.
The main benefit has been seen in rehab, getting a person who's too weak to work at heavy levels, back on their feet again. There's even been consideration of the use of this kind of training for astraunauts who, following Woolfs' and Davis's law do tend to lose it from not using it - their muscle that is.
So, we can start to see with results like this, it would be interesting to understand how low loads with a cuff can cause strength gains equivalent to 80% of a 1RM
Is It Safe?
One of the biggie first questions people have about occlusion is (well, what was yours>) - is - is it safe? The authors respond that by saying they looked at 13 studies with thousands of trials - and even in the one where the forearm was completely occluded for 20mins, there were no measurable ill effects.
Most sessions last only 5-10 mins, and are not full, but partial occlusion.
Likewise, i was reading a 2010 study that wanted to see if thrombosis symptoms would occur in healthy participants - another concern about occlusion - and nothing close to that effect was measured. So from these typical kinds of fears, no such effects it seems have been measured.
The one side effect "acute muscle pain" - i think this means similar to the burn sensation some folks get when going too far in a set. That's common with the "to fatigue" type training used in occlusion. DOMS is also common in the first few bouts. The authors suggest that with these cautions in mind "training combined with ischemia clearly requires a high degree of motivation from the trainee, especially if performed with a high level of effort."
Will that be Wide or Narrow?
The consensus is it seems that wide cuffs have the advantage: lower pressures can be used with wider cuffs. Likewise there are fewer shear force issues with wider cuff and one can stay away from complete occlusion with more control.
Last year i looked at a study that just tied up the lower limbs with wide wraps. Important to note that the cuffs these folks are describing in the research reviews can have the pressure adjusted with the cuff to exact mmHg, similar to a blood pressure cuff.
I make no recommendations about whether it's better to use a proper occlusion cuff or just wrap up a limb; i only note that the places in Japan that have the most experience with this approach use Katsu cuffs - cuffs that enable control of pressure.
Is a Tournequette Even Necessary?
This is my favorite part of the paper because i think there's a link between what is described here, and what is discussed with the Pump (b2d overview here). See what you think.
First the authors point out that studies show the effect of an occlusion cuff is erased once loads get up to 40-60% load. What's interesting is that work using research's favorite - the leg extension - showed that even without a cuff, loads as low as 20% could induce "ischemic pain" - like that's a good thing.
The authors hypothesize that there are ways to get a low load ischemic effect without a cuff by doing the following: partials
So this is where my Pump query comes in: the Pump - if one is not overtraining and under nourished - is easy to achieve by using lots of reps with light loads, until one's arms or related feel like they're so full of blood they can't move. Sounds like kaatsu work.
Now there's been an ongoing debate about whether or not the Pump really leads to hypertrophy. Some of the vigerous come backs are "i never train for the pump and i still get big" - while true not really a defence. And actually, what hasn't been directly tested it seems is post ishemia self-induced, does hypertrophy occur? A lot of body builders will say yes.
What i'm intrigued by is that there seems to be a lot of circumstantial evidence to say that ishemia induced with low loads develops hypertrophy - but if anyone tries to say "and here's why that is" - and they start talking about NO supplements and flushing and who knows what all - you can pretty confidently say, well, based on what research?
In other words, there's a relationship it looks like, but what the actual mechanism is, we don't entirely know. Mybe it's fatiguing out type one and bringing on type II, maybe its IGF-1 goes up and myostatin goes down. Maybe it's mTOR levels. They're all in the soup. But what's cause and what's conincidence - ain't clear. But i sure as heck ain't gonna say the pump is a myth - just the explanations for it so far are pretty mythical.
To Cuff or Not to Cuff
One might think that just going for this kind of non-cuff'd based ischemia (blood pooling; can't flow back) is better than cuff based. Here's what the authors think:
What about the Dose?
To summarise a great long section of this paper, the results are not in for normal training about what the optimal frequence, volume, intensity is for optimal hypertrophic effect using occlusion.
The authors make a great note that not all ischemic training results in strength gains. For some reason, cycling isn't great for occlusion and strength development. On the other hand walk training is one of the big successes of occlusion work, and of course stength training - the short bursts of activity - is where the biggest benefit seems to be. Whether therefore the ratio between ischemia and reperfusion is key here, we just don't know but it seems to be a factor.
Will it Blend
So if we're not rehabbing, and with all the unknowns about dose, is it appropriate to put occlusion training into the mix of a regular strength program with "heavy" resistance.
I dunno.
The authors focus on work that's looked at two great benefits of heavy resistance training: bone mineral density and tendon stiffness.
In both cases lighter load work has been shown to have less of an effect on these factors. So - for ones bones, heavy resistance is a bonus - but then, so is stop and start action. For tendons, however, it seems that volume is also a key factor in enhancing stiffness (MTC descibed here - doesn't mean anything about flexibility, but about load, really)
In other words, while occlusion may not bring on the benefits of heavy resistance, there are other ways than heavy work to enhance these benefits so playing with ischemia may be useful for strength development.
High Volume towards Ischemia? Again, to take another page from bodybuilding and powerlifting practice, mechanisms to increase volume without killing form or inducing failure can be awesome. 
Trainer par excellance Roland Fisher introduced me to the timed sets of Huge in a Hurry
's Chad Waterbury. Very simple: get a weight at the end of a session where you can do 20 reps, and as soon as the fast tempo drops to complete the set, drop the weight, go for another 20. By using time as the marker, there's no way to get to fatigue and form failure. One heck of a pump, too. Thus, one has done their heavy work, and uses the occlusion level sets for a finisher. I love it. Your mileage may vary. See what you find.
Wrap UP - sans wraps even
And speaking of finisher, the authors wrap up with the following. The first sentence for me is key:
Meanwhile, if you wish to try occlusion training yourself, there's only about 4 uni's in the US using it; most work is in Japan. Here's an intereting PDF that talks about a specific Kaatsu cuff system, too.
The point is, i guess, that as this article started, just when we think we know something who'd a thought that strength can be aided by counter-intuitive actions like restricting blood supply? where does that map to evolution?
If nothing else, occlusion work shows us that we are complex systems with more than one path to create an effect.
Related Resources
Citations:
If we asked someone "what should i do to build muscle" probably not a lot of people would say "cut off the blood flow to a working limb." Turns out though, that this latter kind of work - called occlusion training, or blood flow restriction (BFR) - has proven a powerful technique for inducing hypertrophy at very low loads (10-30% of a 1RM). While it's mainly been explored as a rehab technique to help accelerate recovery, some researchers have been looking at it as an approach in regular training. What, then, are the pro's and con's of this technique for training? And what are we learning about the mystery that is hypertrophy from studying the phenomena of occlusion for hypertrohhy strength?These questions are addressed in an excellent review of occlusion research from 2008 called " Ischemic strength training: a low-load alternative to heavy resistance exercise?"
Two of the highlights of the paper (at least for me) -the review of hypertrophy models such as they are and a possible rationale for the Pump in bodybuilding circles.
Overview on the (un)Known of Muscle Building
The authors go through an amazing job of investigating the known models of hypertrophy - and all that we dont know about it - to see where occlusion training may fit in with existing models. Heck, in order to understand what role occlusion plays, we need to have some sense of the depth and breadth of the puddle it's playing in.
Unaccustomed as i am to being brief, i'm actually not going to go through these models in detail here. Suffice it to say though that what we have often thought of as the biggie thing to boost in order to super charge hypertrophy may not hold. The authors do a lovely job of showing for instance that heh, post occlusion training, yes Growth Hormone (GH) is up and IGF-1 is up, but according to all this other research, we really don't know if the presence of these hormone levels is really what's upping protein synthesis at all. Not just hormones, the reviewers look at other factors too - like mechano checmical. THat means that maybe the calcium involved in the actin/myosin bridge that enables contractions is a key to what's really important for hypertrophy - but so far there aren't studies looking at these responses in occlusion, so we have no comparison.
This review is great for myth busting. In other words, its review of what we can actually point to and say "that's what casues muscle growth" shows us what we know is so small, it's really exciting. Why is being able to say "but we don't know if that's what's doing it" exciting? One, it means we're starting to know what's going on in more detail to be able to say we don't know and two, it means in any discussion about somebody saying this is WHY this works (like why the pump "works") we can be pretty confident in knowing they maybe shouldn't be so confident.
It may seem a fine point, but work like this also lets us continue to say that "if you do this protocol, you'll get big" - assuming it's been tested on lots of athletes of various types. What we cannot say with the same confidence is WHY if we follow that protocol we're getting big.
I recommend the full first half of the article just for this review of the state of the art (as of 2008) on hypertrophy.
SO where does this get us then with occlusion and hypertrophy?
First a few words about occlusion training - what is it?
Occlusion training goes by a bunch of names: kaatsu training, occlusion, Blood Flow Restriction (BFR), ishemic training. Occlusion generally means to obstruct or block or even hide something (from view). In the case of muscle work, the blood flow is obstructed, usually by a tournequette of some kind. Ischemia is sort of the technical term for blood flow restriction - to the heart or other body tissue -as a result of some type of block (or occlusion).
Protocols - often seem to involve tournequetting the working limb, then using loads of 10-30% of a 1RM, usually lots of reps, very low rest, until fatigue hits. The results in strength gains are similar to working sets with 80% 1RMs.
The main benefit has been seen in rehab, getting a person who's too weak to work at heavy levels, back on their feet again. There's even been consideration of the use of this kind of training for astraunauts who, following Woolfs' and Davis's law do tend to lose it from not using it - their muscle that is.
So, we can start to see with results like this, it would be interesting to understand how low loads with a cuff can cause strength gains equivalent to 80% of a 1RM
Is It Safe?
One of the biggie first questions people have about occlusion is (well, what was yours>) - is - is it safe? The authors respond that by saying they looked at 13 studies with thousands of trials - and even in the one where the forearm was completely occluded for 20mins, there were no measurable ill effects.
Most sessions last only 5-10 mins, and are not full, but partial occlusion.
Likewise, i was reading a 2010 study that wanted to see if thrombosis symptoms would occur in healthy participants - another concern about occlusion - and nothing close to that effect was measured. So from these typical kinds of fears, no such effects it seems have been measured.
The one side effect "acute muscle pain" - i think this means similar to the burn sensation some folks get when going too far in a set. That's common with the "to fatigue" type training used in occlusion. DOMS is also common in the first few bouts. The authors suggest that with these cautions in mind "training combined with ischemia clearly requires a high degree of motivation from the trainee, especially if performed with a high level of effort."
Will that be Wide or Narrow?
The consensus is it seems that wide cuffs have the advantage: lower pressures can be used with wider cuffs. Likewise there are fewer shear force issues with wider cuff and one can stay away from complete occlusion with more control.Last year i looked at a study that just tied up the lower limbs with wide wraps. Important to note that the cuffs these folks are describing in the research reviews can have the pressure adjusted with the cuff to exact mmHg, similar to a blood pressure cuff.
I make no recommendations about whether it's better to use a proper occlusion cuff or just wrap up a limb; i only note that the places in Japan that have the most experience with this approach use Katsu cuffs - cuffs that enable control of pressure.
Is a Tournequette Even Necessary?
This is my favorite part of the paper because i think there's a link between what is described here, and what is discussed with the Pump (b2d overview here). See what you think.
First the authors point out that studies show the effect of an occlusion cuff is erased once loads get up to 40-60% load. What's interesting is that work using research's favorite - the leg extension - showed that even without a cuff, loads as low as 20% could induce "ischemic pain" - like that's a good thing.
The authors hypothesize that there are ways to get a low load ischemic effect without a cuff by doing the following: partials
Other quadriceps exercises can also be modified to achieve intramuscular restriction of blood flow. During closed kinetic chain exercises such as the squat and the leg press, the force demands of the movement dictate that the electrical activity of the quadriceps is high at flexed knee angles (90°–100°) and low near full-knee extension (Andersen et al., 2006). If the range of motion instead is limited to between ∼50° and 100° of flexion, the muscle activity remains fairly high throughout the movement and intramuscular occlusion is thus more likely to occur.The goal of going for ischemia with low loads is to get the benefit of heavier loads without having to use heavier loads that perhaps could not be taken to the given rep level.
So this is where my Pump query comes in: the Pump - if one is not overtraining and under nourished - is easy to achieve by using lots of reps with light loads, until one's arms or related feel like they're so full of blood they can't move. Sounds like kaatsu work.
Now there's been an ongoing debate about whether or not the Pump really leads to hypertrophy. Some of the vigerous come backs are "i never train for the pump and i still get big" - while true not really a defence. And actually, what hasn't been directly tested it seems is post ishemia self-induced, does hypertrophy occur? A lot of body builders will say yes. What i'm intrigued by is that there seems to be a lot of circumstantial evidence to say that ishemia induced with low loads develops hypertrophy - but if anyone tries to say "and here's why that is" - and they start talking about NO supplements and flushing and who knows what all - you can pretty confidently say, well, based on what research?
In other words, there's a relationship it looks like, but what the actual mechanism is, we don't entirely know. Mybe it's fatiguing out type one and bringing on type II, maybe its IGF-1 goes up and myostatin goes down. Maybe it's mTOR levels. They're all in the soup. But what's cause and what's conincidence - ain't clear. But i sure as heck ain't gonna say the pump is a myth - just the explanations for it so far are pretty mythical.
To Cuff or Not to Cuff
One might think that just going for this kind of non-cuff'd based ischemia (blood pooling; can't flow back) is better than cuff based. Here's what the authors think:
Intuitively, a training model which is based on the muscles own internal restriction of blood flow would have advantages both from a safety point of view and from a practical point of view. On the other hand, in certain muscle groups and in some individuals, it may be difficult to induce relative ischemia at low loads by exercise alone, due to factors such as insufficient intramuscular pressures developed during exercise. Furthermore, it is possible that there are differences between the muscle ischemia resulting from exercise alone and the ischemia induced with a tourniquet in combination with exercise (e.g., a greater build-up of metabolites in the cuff-occluded muscle), which in turn could lead to differences in the stimulation of hypertrophic pathways. Future studies should compare the effects of ischemic training with and without cuff occlusion at the same level of effort.Another great "we don't know" but a great question: is cuffing the same kind of physiological response as non-cuffing occlusion effect?
What about the Dose?
To summarise a great long section of this paper, the results are not in for normal training about what the optimal frequence, volume, intensity is for optimal hypertrophic effect using occlusion.
The authors make a great note that not all ischemic training results in strength gains. For some reason, cycling isn't great for occlusion and strength development. On the other hand walk training is one of the big successes of occlusion work, and of course stength training - the short bursts of activity - is where the biggest benefit seems to be. Whether therefore the ratio between ischemia and reperfusion is key here, we just don't know but it seems to be a factor.
Will it Blend
So if we're not rehabbing, and with all the unknowns about dose, is it appropriate to put occlusion training into the mix of a regular strength program with "heavy" resistance.
I dunno.
The authors focus on work that's looked at two great benefits of heavy resistance training: bone mineral density and tendon stiffness.
In both cases lighter load work has been shown to have less of an effect on these factors. So - for ones bones, heavy resistance is a bonus - but then, so is stop and start action. For tendons, however, it seems that volume is also a key factor in enhancing stiffness (MTC descibed here - doesn't mean anything about flexibility, but about load, really)
In other words, while occlusion may not bring on the benefits of heavy resistance, there are other ways than heavy work to enhance these benefits so playing with ischemia may be useful for strength development.
High Volume towards Ischemia? Again, to take another page from bodybuilding and powerlifting practice, mechanisms to increase volume without killing form or inducing failure can be awesome. Trainer par excellance Roland Fisher introduced me to the timed sets of Huge in a Hurry's Chad Waterbury. Very simple: get a weight at the end of a session where you can do 20 reps, and as soon as the fast tempo drops to complete the set, drop the weight, go for another 20. By using time as the marker, there's no way to get to fatigue and form failure. One heck of a pump, too. Thus, one has done their heavy work, and uses the occlusion level sets for a finisher. I love it. Your mileage may vary. See what you find.Wrap UP - sans wraps even
And speaking of finisher, the authors wrap up with the following. The first sentence for me is key:
By seeing an interesting strength effect from occlusion, that raises the question how is this working in terms of what we know about hypertrophy? Turns out that in asking what we know about hypertrophy, it's surprisingly still very little. Lots about what's happening in the soup with strength training, but not lots of clear A therefore B. Having occlusion in the mix gives us a great point of comparison to be able to say at least what's different with the following factors (or the same) when blood flow is restricted? what's going on that this is happening? That's cool.
The research on resistance exercise performed during ischemic conditions has so far provided important new insights into the physiology of strength training. In addition to being a possible alternative or complement to conventional high-load resistance training in certain situations, ischemic strength training may also have a place in sports training. Because relative ischemia can be induced at rather low loads in certain exercises even without tourniquets, external pressure may not always be necessary to achieve significant training effects. Also, any unique effects of cuff occlusion per se during exercise have yet to be determined because the increased training effects observed in the studies published to date may simply have been due to greater effort. With reference to training combined with cuff occlusion, current evidence suggests that this mode of exercise is relatively safe, but more research is needed especially regarding the potential adverse effects on soft tissues.
Meanwhile, if you wish to try occlusion training yourself, there's only about 4 uni's in the US using it; most work is in Japan. Here's an intereting PDF that talks about a specific Kaatsu cuff system, too. The point is, i guess, that as this article started, just when we think we know something who'd a thought that strength can be aided by counter-intuitive actions like restricting blood supply? where does that map to evolution?
If nothing else, occlusion work shows us that we are complex systems with more than one path to create an effect.
Related Resources
- Occlusion Training
- Get Huge or Die
- Protein Ingestion and Protein Sythesis
- Nutrient Timing for muscle building
- Creatine and Beta Alanine
- Does this stuff work?
- the Pump
Citations:
Tweet Follow @begin2dig
Wernbom M, Augustsson J, & Raastad T (2008). Ischemic strength training: a low-load alternative to heavy resistance exercise? Scandinavian journal of medicine & science in sports, 18 (4), 401-16 PMID: 18466185
Madarame, H., Kurano, M., Takano, H., Iida, H., Sato, Y., Ohshima, H., Abe, T., Ishii, N., Morita, T., & Nakajima, T. (2010). Effects of low-intensity resistance exercise with blood flow restriction on coagulation system in healthy subjects Clinical Physiology and Functional Imaging, 30 (3), 210-213 DOI: 10.1111/j.1475-097X.2010.00927.x
Loenneke, J., & Pujol, T. (2009). The Use of Occlusion Training to Produce Muscle Hypertrophy Strength and Conditioning Journal, 31 (3), 77-84 DOI: 10.1519/SSC.0b013e3181a5a352
PDF
Sunday, September 20, 2009
DOMS Part 2 - what works to reduce/eliminate delayed onset muscle soreness:
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In part 1 we looked at what DOMS is and what's been tried and DOESN'T work to reduce any of its markers from swelling to soreness to reduced ROM and force production.
In this part (II) we look at a range of strategies that seem to attenuate DOMS in a number of ways. My goal in this article is to get to an approach that requires the least gear and seems to have the most benefit.
You will be amazed! So sit back with a nice glass of milk (not kidding), maybe while having a tub (again not kidding) and welcome to the world of muscle repair.
Let's review what's measured in assessing DOMS in the literature.
B2D buddie Mike T. Nelson of extremehumanperformance.com asks the question: is the experience of soreness directly correlated to a drop in performance? Mike in conversation makes the point that pain perception being a brain thing is going to be pretty individual. So how DOMS success is measured is something to bare in mind when looking at the studies following that claim to be effective against DOMS - are we talking DOMS pain reduction (always nice) or performance in a DOMS state?
The following DOMS fighting strategies that researchers claim wins on are:
compression (and compression suits) have been studied
over the past 8 years. In 2001 the well respected Kraemer and crew looked at compression for elbow flexion and saw a lot of benefit across the mutli markers of DOMS:
DOMS pain reduction with Vibration
In a very recent (this month, Sept 2009) study, looking only at perceived pain measures, it seems that vibration plates may have considerable effect at reducing DOMS.
Another intriguing hypothesis is around proprioception: the vibration is causing interneurons to turn down pain signaling. So perhaps an increased pain threshold is happening. Does this mean that the pain reduction is faked? and that the other usual crap around DOMS is still occurring, we just don't feel it? Is that a good idea? Unfortunately the authors do not look at the other markers of DOMS to see what effect is had on them.
DOMS Deminishment- just add water?
The above findings lead us to see that there are some strategies that actually do seem to help with DOMS. But when assessing these treatments, it seems we usually have to make a choice about the effects of care. Massage may reduce some insignificant degree of pain, but not benefit performance in terms of ROM or power generation. Well, there's been some consideration of contrast water therapy for benefiting performance.
In 2008, as if hearing these cautiously optimistic ideas, another study investigates multiple types of temperature immersion:
SO we have several modalities - vibration, if you have access to a plate, compression (with gear on ) and contrast bathing (with all gear off) that seem from repeated studies to have benefits. Of these three compression and contrast bathing have been studied most, with the most consistent results. So just for the sake of full disclosure, there's one study that says they both suck:
DOMS reduction sans gear: DO MORE WORK
Is there any approach that may escape controversy? and also be a little less tool-dependent? Is there a more natural way to fight DOMS as it were?
Some of us at the gym may have tried swapping between hot and cold showers to attempt to replicate the effect of CWI protocols without a tub; i haven't seen any work that's formally checked this, but if you don't have a tub, and aren't keen on setting off a lot of water resources, there may be other approaches.
In 2006, concentric exercises were shown to help offset DOMS.
And just to come back to the question of the value of warm ups discussed in a previous article- here's one more benefit beyond injury prevention: Warm up - light cardio pre unfamiliar eccentric exercises (this is the walking backwards on an inclined treadmill) worked to reduce perceived soreness - but that was the only measure of DOMS, but a not bad one.
My favorite study so far in this space looks at where no other study has dared to go: the complete elimination of DOMS. Give oneself four weeks, and the participant will build in a DOMS eradicator, it seems. Bold claims.
It's important to clarify the protocol: get the heart rate up before each resistance set.
Effectively, the main hypothesis of this study is that keeping an elevated heart rate throughout
a workout helps reduce then eliminate DOMS. Heart rate varied between 60-84% HRR - by contrast the control group heart rate was at 20-39% HRR.
The authors suggest a two part explanation for why their protocol has such a powerful effect. In the first phase (4 weeks) of adaptation, the higher heart rate increases perfusion, getting up lactate and nutrient movement to and from the muscles, clearing out waste.
In discussing this protocol with colleagues when it came out, some were concerned that doing the extra cardio would negatively impact strength work. In anticipation of just this concern, the authors ran a great follow up study to show that quite the opposite was the case. In other words, not only does this protocol sweep away DOMS, it also improves strength work. THat article is discussed in detail in Does Cardio Interfere with Strength Training: How 'bout No?
Now i'd be happy to end here with the best recommendations being that while CWI is grand it's not generally available, and so, for both the benefits of eliminating DOMS and improving strength work, the Santa Cruz group approach is optimal. But there are just a few more things to consider for improving/lessening one's DOMS experience.
DOMS: Got Milk? What about Protease or BCAAs?
In 2007, a study looked at the effect of protease used for DOMS. Now protease is most often found as an enzyme added to proteins like whey to assist in their digestion. We know that muscles use amino acids from proteins to repair muscles, so it makes sense, rather that if these enzymes are present to optimize proteins' digestion so more amino acids area available, that sounds like a good thing. But then so did having more vitamin c - and it wasn't. Protease, however, looks pretty good.
Going a step further, it seems that pumping up the volume of milk after those eccentrics can actually accelerate muscle repair and get performance back faster than without it. Here, the authors claim that (unlike protease alone) that those important blood markers like CK and myoglobin are also better off from a dose of milk. As far as i know no one has gone head to head between CWI and Milk for increasing repair rate and decreasing DOMS, but again, if those immersion tanks aren't there, and you haven't been cardio'ing for the 4 weeks yet. This may be yet one more reason to value milk as a recovery drink. Milk offers no help for soreness however. Alas.
In this part (II) we look at a range of strategies that seem to attenuate DOMS in a number of ways. My goal in this article is to get to an approach that requires the least gear and seems to have the most benefit.
You will be amazed! So sit back with a nice glass of milk (not kidding), maybe while having a tub (again not kidding) and welcome to the world of muscle repair.
Let's review what's measured in assessing DOMS in the literature.
- what's in the blood: usually there are markers in the blood like creatine kinase and LDH - these are markers of muscle damage - we may have the same CK levels and have very different responses to soreness
- then there's the subjective measures of soreness themselves using rating scales.
- then there's the more objective bits: Range of motion and force production.
B2D buddie Mike T. Nelson of extremehumanperformance.com asks the question: is the experience of soreness directly correlated to a drop in performance? Mike in conversation makes the point that pain perception being a brain thing is going to be pretty individual. So how DOMS success is measured is something to bare in mind when looking at the studies following that claim to be effective against DOMS - are we talking DOMS pain reduction (always nice) or performance in a DOMS state?
The following DOMS fighting strategies that researchers claim wins on are:
- Gear that works on: compression
- gear that works off: tubs
- what works sans gear: get the heart rate up and keep it up
- What to ingest that might help these mods further (milk, bcaa, protease?)
compression (and compression suits) have been studied
over the past 8 years. In 2001 the well respected Kraemer and crew looked at compression for elbow flexion and saw a lot of benefit across the mutli markers of DOMS:J Orthop Sports Phys Ther. 2001 Jun;31(6):282-90.In 2006, another study seemed to reinforce these findings
Influence of compression therapy on symptoms following soft tissue injury from maximal eccentric exercise.
Kraemer WJ, Bush JA, Wickham RB, Denegar CR, Gómez AL, Gotshalk LA, Duncan ND, Volek JS, Putukian M, Sebastianelli WJ.The Human Performance Laboratory, Ball State University, Muncie, Ind 47306, USA. wkraemer@bsu.edu
STUDY DESIGN: A between groups design was used to compare recovery following eccentric muscle damage under 2 experimental conditions. OBJECTIVE: To determine if a compression sleeve donned immediately after maximal eccentric exercise would enhance recovery of physical function and decrease symptoms of soreness. BACKGROUND: Prior investigations using ice, intermittent compression, or exercise have not shown efficacy in relieving symptoms of delayed onset muscle soreness (DOMS). To date, no study has shown the effect of continuous compression on DOMS, yet this would offer a low cost intervention for patients suffering with the symptoms of DOMS. METHODS AND MEASURES: Twenty nonimpaired non-strength-trained women participated in the study. Subjects were matched for age, anthropometric data, and one repetition maximum concentric arm curl strength and then randomly placed into a control group (n = 10) or an experimental compression sleeve group (n = 10). Subjects were instructed to avoid pain-relieving modalities (eg, analgesic medications, ice) throughout the study. The experimental group wore a compressive sleeve garment for 5 days following eccentric exercise. Subjects performed 2 sets of 50 passive arm curls with the dominant arm on an isokinetic dynamometer with a maximal eccentric muscle action superimposed every fourth passive repetition. One repetition maximum elbow flexion, upper arm circumference, relaxed elbow angle, blood serum cortisol, creatine kinase, lactate dehydrogenase, and perception of soreness questionnaires were collected prior to the exercise bout and daily thereafter for 5 days. RESULTS: Creatine kinase was significantly elevated from the baseline value in both groups, although the experimental compression test group showed decreased magnitude of creatine kinase elevation following the eccentric exercise. Compression sleeve use prevented loss of elbow motion, decreased perceived soreness, reduced swelling, and promoted recovery of force production.
The low oxidative demand and muscular adaptations accompanying eccentric exercise hold benefits for both healthy and clinical populations. Compression garments have been suggested to reduce muscle damage and maintain muscle function. This study investigated whether compression garments could benefit metabolic recovery from eccentric exercise. Following 30-min of downhill walking participants wore compression garments on one leg (COMP), the other leg was used as an internal, untreated control (CONT). The muscle metabolites phosphomonoester (PME), phosphodiester (PDE), phosphocreatine (PCr), inorganic phosphate (Pi) and adenosine triphosphate (ATP) were evaluated at baseline, 1-h and 48-h after eccentric exercise using 31P-magnetic resonance spectroscopy. Subjective reports of muscle soreness were recorded at all time points. The pressure of the garment against the thigh was assessed at 1-h and 48-h following exercise. There was a significant increase in perceived muscle soreness from baseline in both the control (CONT) and compression (COMP) leg at 1-h and 48-h following eccentric exercise (p <>2+ or PME at any time point or between CONT and COMP legs. Eccentric exercise causes disruption of pH control in skeletal muscle but does not cause disruption to cellular control of free energy. Compression garments may alter potential indices of the repair processes accompanying structural damage to the skeletal muscle following eccentric exercise allowing a faster cellular repairWhat we don't see clearly in the above piece is a measure of force production and range of motion. So more recently (2009) again, a thumbs up on attenuation from compression:
Delayed onset muscle soreness (DOMS) is a common experience following unaccustomed eccentric exercise. DOMS and associated force deficits may limit optimal performance in subsequent days. The cause of DOMS remains poorly understood, thus there is no effective treatment. Graduated compression stockings (GCS) are a commonly used intervention believed to diminish DOMS. The purpose of this study was to determine if GCS after eccentric walking exercise minimizes DOMS and associated deficits (e.g. muscle force capacity). Eight healthy subjects (age 26±4 yrs, height 175±8 cm, weight 70±5 kg) volunteered to perform a single bout of backward downhill walking exercise (duration 30 min, velocity 1 m.s-1, negative grade-25%, load 12% of body weight). Following walking exercise, subjects were required to wear 5 hours per day for 3 consecutive days GSC (SupportivTM) on one leg while the second was used as control. Muscle soreness and neuromuscular measures (M-wave, peak twitch, maximal voluntary torque or MVT) were taken pre and postwalk, then 2, 24, 48 and 72 hours post-walking exercise for the two legs. There was a 28% reduction in DOMS 72 h after exercise when wearing GCS (P<0.05)>This list of refs is not complete, but it is largely indicative of results. Now, while some companies sell whole body compression suits - claiming a whole host of performance benefits, to my knowledge whole suits have not been tested on DOMS, but there does seem to be attenuation with compression.
DOMS pain reduction with Vibration
In a very recent (this month, Sept 2009) study, looking only at perceived pain measures, it seems that vibration plates may have considerable effect at reducing DOMS.
J Strength Cond Res. 2009 Sep;23(6):1677-82.Click here to read LinksIntriguingly use of EMT (rapid pulsed contraction of muscles) has not had success in treating DOMS but this shaking does. The authors hypothesize that the reason for the effect may be enhanced local blood flow to move waste products out of the muscles faster.
Effect of iTonic whole-body vibration on delayed-onset muscle soreness among untrained individuals.
Rhea MR, Bunker D, Marín PJ, Lunt K.
A.T. Still University, Mesa, Arizona, 85206, USA. mrhea@atsu.edu
Attempts to reduce or eliminate delayed-onset of muscle soreness are important asthis condition is painful and debilitating. The purpose of this study was to examine the effectiveness of whole-body vibration (WBV) massage and stretching exercises at reducing perceived pain among untrained men. Sixteen adult men (age, 36.6 +/- 2.1 yr) volunteered to perform a strenuous exercise session consisting of resistance training and repeated sprints. Subjects were randomly assigned to 1 of 2 recovery groups: a group performing WBV stretching sessions or a stretching group performing static stretching without vibration. Both groups performed similar stretches, twice per day for 3 days after the workout. The vibration group performed their stretches on the iTonic platform (frequency, 35 Hz; amplitude, 2 mm). Perceived pain was measured at 12, 24, 48, and 72 hours postworkout. Statistical analyses identified a significantly lower level of reported perceived pain at all postworkout measurement times among the WBV group.
Another intriguing hypothesis is around proprioception: the vibration is causing interneurons to turn down pain signaling. So perhaps an increased pain threshold is happening. Does this mean that the pain reduction is faked? and that the other usual crap around DOMS is still occurring, we just don't feel it? Is that a good idea? Unfortunately the authors do not look at the other markers of DOMS to see what effect is had on them.
DOMS Deminishment- just add water?
The above findings lead us to see that there are some strategies that actually do seem to help with DOMS. But when assessing these treatments, it seems we usually have to make a choice about the effects of care. Massage may reduce some insignificant degree of pain, but not benefit performance in terms of ROM or power generation. Well, there's been some consideration of contrast water therapy for benefiting performance.Just to be clear on what CWT means here the authors write:
J Strength Cond Res. 2007 Aug;21(3):697-702.Links
The effect of contrast water therapy on symptoms of delayed onset muscle soreness.
Vaile JM, Gill ND, Blazevich AJ.
Department of Physiology, Australian Institute of Sport, Canberra, Australia.
This study examined the effect of contrast water therapy (CWT) on the physiological and functional symptoms of delayed onset muscle soreness (DOMS) following DOMS-inducing leg press exercise. Thirteen recreational athletes performed 2 experimental trials separated by 6 weeks in a randomized crossover design. On each occasion, subjects performed a DOMS-inducing leg press protocol consisting of 5 x 10 eccentric contractions (180 seconds recovery between sets) at 140% of 1 repetition maximum (1RM). This was followed by a 15-minute recovery period incorporating either CWT or no intervention, passive recovery (PAS). Creatine kinase concentration (CK), perceived pain, thigh volume, isometric squat strength, and weighted jump squat performance were measured prior to the eccentric exercise, immediately post recovery, and 24, 48, and 72 hours post recovery. Isometric force production was not reduced below baseline measures throughout the 72-hour data collection period following CWT ( approximately 4-10%). However, following PAS, isometric force production (mean +/- SD) was 14.8 +/- 11.4% below baseline immediately post recovery (p < size =" 0.76)."> 0.01) differences in perceived pain between treatments. Contrast water therapy was associated with a smaller reduction, and faster restoration, of strength and power measured by isometric force and jump squat production following DOMS-inducing leg press exercise when compared to PAS. Therefore, CWT seems to be effective in reducing and improving the recovery of functional deficiencies that result from DOMS, as opposed to passive recovery.
where subjects immersed their lower body to the level of the anterior superior iliac spine alternately between 2 baths—immersion for 60 seconds in cold water (8–10 degrees C) followed immediately by immersion for 120 sec- onds in hot water (40–42 degrees C); subjects alternated between the 2 baths for a total of 15 minutes.As the authors suggest for practical applications (a nice feature of JSC articles)
The present results indicate that CWT can significantly reduce swelling. It is hypothesized that CWT The findings of this study indicate that strength, power, and symptoms of DOMS are improved following CWT compared to passive recovery. These improvements in the recovery profile support CWT as a practical and low-cost recovery strategy. Therefore, CWT appears to be a recovery strategy that could easily be adopted and integrated into athletes’ recovery programs.The authors are also reasonably cautious about their results:
The results of the present study are the first to provide positive scientific support for the practice of CWT. While CWT has been acknowledged in sports medicine as a recovery strategy for the treatment of postacute soft- tissue injury (21), there is an apparent lack of knowledge surrounding its use as a recovery strategy to alleviate muscle soreness and enhance the recovery of various physiological factors. Although the results of the present study support the use of CWT, further research into its use is required to develop knowledge and information in the area of this recovery strategy, with an emphasis on gaining understanding into the possible physiological mechanisms of CWT. Given that the CWT protocol used in the present study was successful in minimizing force loss and promoting recovery, it could be used as a template for future studies. Despite its positive affect on muscle force generation, the long-term effects of CWT are not known. Some caution should therefore be exercised with its prolonged use until its effects on long-term muscle adaptation are fully understood.In other words, CWT seems to have an effect in reducing non-pain symptoms of DOMS to get athletes up to force and speed faster than without it, but we don't know exactly why or how it's working. We don't want to be damaging anything, so let's keep looking at this phenomenon.
In 2008, as if hearing these cautiously optimistic ideas, another study investigates multiple types of temperature immersion:
Eur J Appl Physiol. 2008 Mar;102(4):447-55. Epub 2007 Nov 3.The happy thing is that there seem to be some benefits from all sorts of immersions: just hot, contrast and just cold. The main difference is that contrast water therapy had the best effect on all markers when checked at 24, 48 and 72 hours. Cold water only kicks in with force recovery at 48 hours. Now my personal pref, hot water, is shown to improve isometric force - that's good. But apparently that's it. Weighted squat jump, perceived pain, thigh girths and blood variables didn't change. Best on all markers though is the protocol hit upon by the 2007 study: contrast water immersion: going from short cold to longer hot, back and forth.
Erratum in: Eur J Appl Physiol. 2008 May;103(1):121-2.
Effect of hydrotherapy on the signs and symptoms of delayed onset muscle soreness.
Vaile J, Halson S, Gill N, Dawson B.
Department of Physiology, Australian Institute of Sport, PO Box 176, Belconnen, ACT, Australia. jo.vaile@ausport.gov.au
This study independently examined the effects of three hydrotherapy interventions on the physiological and functional symptoms of delayed onset muscle soreness (DOMS). Strength trained males (n = 38) completed two experimental trials separated by 8 months in a randomised crossover design; one trial involved passive recovery (PAS, control), the other a specific hydrotherapy protocol for 72 h post-exercise; either: (1) cold water immersion (CWI: n = 12), (2) hot water immersion (HWI: n = 11) or (3) contrast water therapy (CWT: n = 15). For each trial, subjects performed a DOMS-inducing leg press protocol followed by PAS or one of the hydrotherapy interventions for 14 min. Weighted squat jump, isometric squat, perceived pain, thigh girths and blood variables were measured prior to, immediately after, and at 24, 48 and 72 h post-exercise. Squat jump performance and isometric force recovery were significantly enhanced.
SO we have several modalities - vibration, if you have access to a plate, compression (with gear on ) and contrast bathing (with all gear off) that seem from repeated studies to have benefits. Of these three compression and contrast bathing have been studied most, with the most consistent results. So just for the sake of full disclosure, there's one study that says they both suck:
- Med Sci Sports Exerc. 2008 Jul;40(7):1297-306.
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The effects of contrast bathing and compression therapy on muscular performance.
English Institute of Sport, North East Region, Gateshead International Stadium, Gateshead, Tyne and Wear, UNITED KINGDOM. duncan.french@eis2win.co.uk
Contrast bathing (CB) and compression garments (CG) are widely used to promote recovery. PURPOSE: To evaluate CB and CG as regeneration strategies after exercise-induced muscle damage (EIMD). METHODS: Baseline values of muscle soreness, serum creatine kinase (CK) and myoglobin (Mb), joint range of motion, limb girth, 10- or 30-m sprint, countermovement jump (CMJ), and five repetition maximum squat were completed by 26 young men who then undertook a resistance exercise challenge (REC) to induce EIMD: 6 x 10 parallel squats at 100% body weight with 5-s one repetition maximum eccentric squat superimposed onto each set. After the REC, subjects were separated into three intervention groups: CB, CG, and control (CONT). Forty-eight hours after REC, the subjects exercise performance was reassessed. CK and Mb were also measured +1, +24, and +48 h post-REC. RESULTS: CK was elevated at +24 h ( upward arrow140%; upward arrow161%; upward arrow270%), and Mb was elevated at +1 h ( upward arrow523%; upward arrow458%; upward arrow682%) in CB, CG, and CONT. Within-group large effect sizes for loge[CK] were found for CB at +24 h (0.80) and +48 h (0.84). Area under the [Mb] curve was lower in CB compared with CG and CONT (P < or =" 0.05).">
DOMS reduction sans gear: DO MORE WORK
Is there any approach that may escape controversy? and also be a little less tool-dependent? Is there a more natural way to fight DOMS as it were?
Some of us at the gym may have tried swapping between hot and cold showers to attempt to replicate the effect of CWI protocols without a tub; i haven't seen any work that's formally checked this, but if you don't have a tub, and aren't keen on setting off a lot of water resources, there may be other approaches.
In 2006, concentric exercises were shown to help offset DOMS.
Appl Physiol Nutr Metab. 2006 Apr;31(2):126-34.Click here to read LinksOk, so concentrics help reduce pain, but don't do anything for performance. What about light eccentrics?
Light concentric exercise has a temporarily analgesic effect on delayed-onset muscle soreness, but no effect on recovery from eccentric exercise.
Zainuddin Z, Sacco P, Newton M, Nosaka K.
School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.
This study investigated the hypothesis that a bout of light concentric exercise (LCE) would alleviate delayed-onset muscle soreness (DOMS) and enhance recovery from muscle damage. Fourteen subjects performed two bouts of 60 maximal eccentric actions of the elbow flexors (Max-ECC) separated by 2-4 weeks. One arm performed LCE (600 elbow flexion and extension actions with minimal force generation) 1, 2, 3, and 4 d after Max-ECC; the contralateral (control) arm performed only Max-ECC. Changes in maximal isometric and isokinetic strength, range of motion (ROM), upper arm circumference, and muscle soreness and tenderness were assessed before and immediately after LCE bouts. Changes in these measures and plasma creatine kinase (CK) activity for 7 d after Max-ECC were compared between the control and LCE arms using 2-way repeated measures analysis of variance (ANOVA). Significant (p < style="color: rgb(102, 51, 0);">These results suggest that LCE has a temporary analgesic effect on DOMS, but no effect on recovery from muscle damage.
J Sci Med Sport. 2008 Jun;11(3):291-8. Epub 2007 Aug 17.Click here to read LinksThese low load high volume eccentrics have also been seen as a mitigating prep against DOMS. Indeed, approaches to strength building like Kenneth Jay's Beast training protocol of alternating high volume lighter load days (a variant described here) with low volume higher load days may be just right - just remember to start with the high volume.
A light load eccentric exercise confers protection against a subsequent bout of more demanding eccentric exercise.
Lavender AP, Nosaka K.
Graduate School of Integrated Science, Yokohama City University, Yokohama, Japan.
This study investigated the hypothesis that a light eccentric exercise (ECC) that does not induce a loss of muscle function and delayed onset muscle soreness would confer a protective effect against a more strenuous ECC. Eighteen young men were randomly placed into two groups: 10-40% (n=9) and 40% (n=9). Subjects in the 10-40% group performed ECC of the elbow flexors (six sets of five reps) using a dumbbell set at 10% of maximal isometric strength (MVC) at an elbow joint angle of 90 degrees , followed 2 days later by ECC using a dumbbell weight of 40% MVC. Subjects in the 40% group performed the 40% ECC only. Changes in MVC, range of motion (ROM), upper arm circumference (CIR), plasma creatine kinase (CK) activity and muscle soreness before, immediately after, 1-5 and 7 days following the 40% ECC were compared between groups by a two-way repeated measures ANOVA. No significant changes in any of the criterion measures were found immediately and 1-2 days after the 10% ECC. Following the 40% ECC, the 10-40% group showed significantly (P<0.05) style="color: rgb(102, 51, 0);" style="color: rgb(102, 51, 0);">These results suggest that the 10% ECC induced some protection against a subsequent bout of 40% ECC performed 2 days later. It appears that the light eccentric exercise preconditioned the muscles for exposure to the subsequent damaging eccentric exercise bout.
And just to come back to the question of the value of warm ups discussed in a previous article- here's one more benefit beyond injury prevention: Warm up - light cardio pre unfamiliar eccentric exercises (this is the walking backwards on an inclined treadmill) worked to reduce perceived soreness - but that was the only measure of DOMS, but a not bad one.
Aust J Physiother. 2007;53(2):91-5.Note the paper only measures perceived soreness rather than looking at performance factors.
Warm-up reduces delayed onset muscle soreness but cool-down does not: a randomised controlled trial.
Law RY, Herbert RD.
The University of Sydney, Australia.
QUESTION: Does warm-up or cool-down (also called warm-down) reduce delayed-onset muscle soreness? DESIGN: Randomised controlled trial of factorial design with concealed allocation and intention-to-treat analysis. PARTICIPANTS: Fifty-two healthy adults (23 men and 29 women aged 17 to 40 years). INTERVENTION: Four equally-sized groups received either warm-up and cool-down, warm-up only, cool-down only, or neither warm-up nor cool-down. All participants performed exercise to induce delayed-onset muscle soreness, which involved walking backwards downhill on an inclined treadmill for 30 minutes. The warm-up and cool-down exercise involved walking forwards uphill on an inclined treadmill for 10 minutes. OUTCOME MEASURE: Muscle soreness, measured on a 100-mm visual analogue scale. RESULTS: Warm-up reduced perceived muscle soreness 48 hours after exercise on the visual analogue scale (mean effect of 13 mm, 95% CI 2 to 24 mm). However cool-down had no apparent effect (mean effect of 0 mm, 95% CI -11 to 11 mm). CONCLUSION: Warm-up performed immediately prior to unaccustomed eccentric exercise produces small reductions in delayed-onset muscle soreness but cool-down performed after exercise does not.
My favorite study so far in this space looks at where no other study has dared to go: the complete elimination of DOMS. Give oneself four weeks, and the participant will build in a DOMS eradicator, it seems. Bold claims.
J Strength Cond Res. 2008 Jan;22(1):212-25.
Elimination of delayed-onset muscle soreness by pre-resistance cardioacceleration before each set.
Davis WJ, Wood DT, Andrews RG, Elkind LM, Davis WB.
Division of Physical and Biological Sciences, University of California at Santa Cruz, Santa Cruz, California, USA. jackson@MiracleWorkout.com
We compared delayed-onset muscle soreness (DOMS) induced by anaerobic resistance exercises with and without aerobic cardioacceleration before each set, under the rationale that elevated heart rate (HR) may increase blood perfusion in muscles to limit eccentric contraction damage and/or speed muscle recovery. In two identical experiments (20 men, 28 women), well-conditioned athletes paired by similar physical condition were assigned randomly to experimental or control groups. HR (independent variable) was recorded with HR monitors. DOMS (dependent variable) was self-reported using Borg's Rating of Perceived Pain scale. After identical pre-training strength testing, mean DOMS in the experimental and control groups was indistinguishable (P > or = 0.19) for musculature employed in eight resistance exercises in both genders, validating the dependent variable. Subjects then trained three times per week for 9 (men) to 11 (women) weeks in a progressive, whole-body, concurrent training protocol. Before each set of resistance exercises, experimental subjects cardioaccelerated briefly (mean HR during resistance training, 63.7% HR reserve), whereas control subjects rested briefly (mean HR, 33.5% HR reserve). Mean DOMS among all muscle groups and workouts was discernibly less in experimental than control groups in men (P = 0.0000019) and women (P = 0.0007); less for each muscle group used in nine resistance exercises in both genders, discernible (P > 0.025) in 15 of 18 comparisons; and less in every workout, discernible (P > 0.05) in 32% (men) and 55% (women) of workouts. Most effect sizes were moderate. In both genders, mean DOMS per workout disappeared by the fourth week of training in experimental but not control groups. Aerobic cardioacceleration immediately before each set of resistance exercises therefore rapidly eliminates DOMS during vigorous progressive resistance training in athletes.
It's important to clarify the protocol: get the heart rate up before each resistance set.
Effectively, the main hypothesis of this study is that keeping an elevated heart rate throughout
a workout helps reduce then eliminate DOMS. Heart rate varied between 60-84% HRR - by contrast the control group heart rate was at 20-39% HRR.The authors suggest a two part explanation for why their protocol has such a powerful effect. In the first phase (4 weeks) of adaptation, the higher heart rate increases perfusion, getting up lactate and nutrient movement to and from the muscles, clearing out waste.
In this first stage, therefore, the increased muscle perfusion induced by pre-resistance cardioacceleration retards cellular destruction induced by eccentric contraction and/or accelerates tissue repair, limiting muscle inflammation and therefore reducing DOMS in the first few workouts.In the second stage, post 4 weeks when the DOMS is eliminated, basically the same effects being built in phase one are in phase two established and fully operational: an expanding peripheral vascular bed is established with better capilarization meaning that repair can happen more effectively to the muscles.
In discussing this protocol with colleagues when it came out, some were concerned that doing the extra cardio would negatively impact strength work. In anticipation of just this concern, the authors ran a great follow up study to show that quite the opposite was the case. In other words, not only does this protocol sweep away DOMS, it also improves strength work. THat article is discussed in detail in Does Cardio Interfere with Strength Training: How 'bout No?
Now i'd be happy to end here with the best recommendations being that while CWI is grand it's not generally available, and so, for both the benefits of eliminating DOMS and improving strength work, the Santa Cruz group approach is optimal. But there are just a few more things to consider for improving/lessening one's DOMS experience.
DOMS: Got Milk? What about Protease or BCAAs?
In 2007, a study looked at the effect of protease used for DOMS. Now protease is most often found as an enzyme added to proteins like whey to assist in their digestion. We know that muscles use amino acids from proteins to repair muscles, so it makes sense, rather that if these enzymes are present to optimize proteins' digestion so more amino acids area available, that sounds like a good thing. But then so did having more vitamin c - and it wasn't. Protease, however, looks pretty good.J Strength Cond Res. 2007 Aug;21(3):661-7.LinksSo what seems to be happening is that there's an effect of protease associated with better muscle strength - reducing strength loss right after exercise - but so far that's it. Pain is still there. Go get in a cold tub.
Effects of a protease supplement on eccentric exercise-induced markers of delayed-onset muscle soreness and muscle damage.
Beck TW, Housh TJ, Johnson GO, Schmidt RJ, Housh DJ, Coburn JW, Malek MH, Mielke M.
Department of Nutrition and Health Sciences, Human Performance Laboratory University of Nebraska-Lincoln, Lincoln, Nebraska 68583, USA. tbeck@unlserve.unl.edu
This investigation examined the effects of a protease supplement on selected markers of muscle damage and delayed-onset muscle soreness (DOMS). The study used a double-blinded, placebo-controlled, crossover design. Twenty men (mean +/- SD age = 21.0 +/- 3.1 years) were randomly assigned to either a supplement group (SUPP) or a placebo group (PLAC). All subjects were tested for unilateral isometric forearm flexion strength, hanging joint angle, relaxed arm circumference, subjective pain rating, and plasma creatine kinase activity and myoglobin concentration. The testing occurred before (TIME1), immediately after (TIME2), and 24 (TIME3), 48 (TIME4), and 72 (TIME5) hours after a bout of eccentric exercise. During these tests, the subjects in the SUPP group ingested a protease supplement. The subjects in the PLAC group took microcrystalline cellulose. After testing at TIME5 and 2 weeks of rest, the subjects were crossed over into the opposite group and performed the same tests as during visits 1-5, but with the opposite limb. Overall, isometric forearm flexion strength was greater (7.6%) for the SUPP group than for the PLAC group, despite nearly identical (difference = 0.14 N.m, p = 0.940) mean strength values before (TIME1) the eccentric exercise protocol. There were no between-group differences for hanging joint angle, relaxed arm circumference, subjective pain ratings, and plasma creatine kinase activity and myoglobin concentration from TIME1 to TIME5. These findings provided initial evidence that the protease supplement may be useful for reducing strength loss immediately after eccentric exercise and for aiding in short-term strength recovery. The protease supplement had no effect, however, on the perception of pain associated with DOMS or the blood markers of muscle damage.
Going a step further, it seems that pumping up the volume of milk after those eccentrics can actually accelerate muscle repair and get performance back faster than without it. Here, the authors claim that (unlike protease alone) that those important blood markers like CK and myoglobin are also better off from a dose of milk. As far as i know no one has gone head to head between CWI and Milk for increasing repair rate and decreasing DOMS, but again, if those immersion tanks aren't there, and you haven't been cardio'ing for the 4 weeks yet. This may be yet one more reason to value milk as a recovery drink. Milk offers no help for soreness however. Alas.
Appl Physiol Nutr Metab. 2008 Aug;33(4):775-83.Click here to read LinksTweet Follow @begin2dig
Acute milk-based protein-CHO supplementation attenuates exercise-induced muscle damage.
Cockburn E, Hayes PR, French DN, Stevenson E, St Clair Gibson A.
Division of Sports Sciences, Northumbria University, Newcastle, UK. e.cockburn@unn.ac.uk
Exercise-induced muscle damage (EIMD) leads to the degradation of protein structures within the muscle. This may subsequently lead to decrements in muscle performance and increases in intramuscular enzymes and delayed-onset muscle soreness (DOMS). Milk, which provides protein and carbohydrate (CHO), may lead to the attenuation of protein degradation and (or) an increase in protein synthesis that would limit the consequential effects of EIMD. This study examined the effects of acute milk and milk-based protein-CHO (CHO-P) supplementation on attenuating EIMD. Four independent groups of 6 healthy males consumed water (CON), CHO sports drink, milk-based CHO-P or milk (M), post EIMD. DOMS, isokinetic muscle performance, creatine kinase (CK), and myoglobin (Mb) were assessed immediately before and 24 and 48 h after EIMD. DOMS was not significantly different (p > 0.05) between groups at any time point. Peak torque (dominant) was significantly higher(p <>
And one more: BCAA's may be good in that they simply help reduce muscle damage, something the authors assert leads to DOMS. The authors do not claim however that BCAA's reduce DOMS, but that they sure do lots of good things related to this.J Sports Med Phys Fitness. 2008 Sep;48(3):347-51.LinksAnd just a final aside, in another galaxy that looks at occlusion training and hypertrophy, here's one study looking at occlusion (here called Blood Flow Restriction). We won't get into the why's and wherefores of occlusion training, but here's a discussion of recent research and rationals of same.
Branched-chain amino acid supplementation does not enhance athletic performance but affects muscle recovery and the immune system.
Negro M, Giardina S, Marzani B, Marzatico F.
Pharmacobiochemistry Laboratory, Section of Pharmacology and Pharmacological Biotechnology, Department of Cellular and Molecular, Physiological and Pharmacological Sciences, University of Pavia, Pavia, Italy.
Since the 1980's there has been high interest in branched-chain amino acids (BCAA) by sports nutrition scientists. The metabolism of BCAA is involved in some specific biochemical muscle processes and many studies have been carried out to understand whether sports performance can be enhanced by a BCAA supplementation. However, many of these researches have failed to confirm this hypothesis. Thus, in recent years investigators have changed their research target and focused on the effects of BCAA on the muscle protein matrix and the immune system. Data show that BCAA supplementation before and after exercise has beneficial effects for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis. Muscle damage develops delayed onset muscle soreness: a syndrome that occurs 24-48 h after intensive physical activity that can inhibit athletic performance. Other recent works indicate that BCAA supplementation recovers peripheral blood mononuclear cell proliferation in response to mitogens after a long distance intense exercise, as well as plasma glutamine concentration. The BCAA also modifies the pattern of exercise-related cytokine production, leading to a diversion of the lymphocyte immune response towards a Th1 type. According to these findings, it is possible to consider the BCAA as a useful supplement for muscle recovery and immune regulation for sports events.
Suffice it to showing that unlike non-occluded work, BFR can elicit DOMS from concentric and eccentric work, and resting soreness is worse in the concentric case. I would just never have thought of that.Eur J Appl Physiol. 2009 Aug 29. [Epub ahead of print]Click here to read LinksSo while BFR can have real benefits for training and for rehab in certain populations, it seems it can also get a person both coming and going with DOMS. Add that to your thoughts next time you want to squat with a tourniquet around your thighs. That said, most occlusion training is in the low load low volume region, so hmm.
Delayed-onset muscle soreness induced by low-load blood flow-restricted exercise.
Umbel JD, Hoffman RL, Dearth DJ, Chleboun GS, Manini TM, Clark BC.
Institute for Neuromusculoskeletal Research, Ohio University, Athens, OH, USA.
We performed two experiments to describe the magnitude of delayed-onset muscle soreness (DOMS) associated with blood flow restriction (BFR) exercise and to determine the contribution of the concentric (CON) versus eccentric (ECC) actions of BFR exercise on DOMS. In experiment 1, nine subjects performed three sets of unilateral knee extension BFR exercise at 35% of maximal voluntary contraction (MVC) to failure with a thigh cuff inflated 30% above brachial systolic pressure. Subjects repeated the protocol with the contralateral limb without flow restriction. Resting soreness (0-10 scale) and algometry (pain-pressure threshold; PPT) were assessed before and 24, 48 and 96 h post-exercise. Additionally, MVC and vastus lateralis cross-sectional area (CSA) were measured as indices of exercise-induced muscle damage. At 24-h post-exercise, BFR exercise resulted in more soreness than exercise without BFR (2.8 +/- 0.3 vs 1.7 +/- 0.5) and greater reductions in PPT (15.2 +/- 1.7 vs. 20 +/- 2.3 N) and MVC (14.1 +/- 2.5% decrease vs. 1.5 +/- 4.5% decrease) (p <= 0.05). In experiment 2, 15 different subjects performed three sets of unilateral BFR exercise at 35% MVC with one limb performing only the CON action and the contralateral performing the ECC action. The aforementioned indices of DOMS were assessed before exercise and 24, 48 and 96 h post-exercise. At 24 h post-exercise, CON BFR exercise resulted in more resting soreness than ECC BFR exercise (3.0 +/- 0.5 vs. 1.6 +/- 0.4), and a greater decrease in MVC (9.8 +/- 2.7% decrease vs. 3.4 +/- 2.5% decrease) (p <=0.05). These data suggest that knee extension BFR exercise induces mild DOMS and that BFR exercise elicits muscle damage under atypical conditions with low-tension concentric contractions.
Summary: Avoiding, Reducing, Eliminating DOMS
We've seen that there's more going on in DOMS than simply sore muscles. Reduced ROM, limb swelling, reduced power output and various internal effects on CK and myoglobin to name two are all triggered - in ways that fatigue alone for instance does not induce.
As for dealing with DOMS effects, when luxury affords, jumping between cold (shorter) and hot (longer. yay!) immersions is also very effective.
Passive manual therapies like acupuncture and massage seem to do nothing for DOMS but vibration plates do seem to have an effect on pain perception. Compression garments may have even greater effect.
Of all the techniques proposed, the most consistently effective, doable by anyone, DOMS reducers are active interventions, from doing light warm ups, to lighter load sets of a main eccentric movement days before, to my fave, and seemingly the most effective, doing cardio *within* a resistance workout that has that new intensity or unfamiliar level of eccentric activity to it. Doing cardio within sets (ie keeping the HR up throughout the efforts) is the only protocol to claim that within 4 weeks, DOMS can be eliminated - and strength improvements increased concurrently.
So if you want to kill off DOMS in your resistance training work, keep your heart rate up before you lift, pull or push (between 60-84% of HRR ) and after 4 weeks of that, pending keeping up the program, DOMS will be a memory and something you have to commiserate with your friends about while you escape, getting stronger while you're at it.
And possibly, if you want to amp up the recovery, throw some whey protein with protease into a glass of milk and add some BCAA's to that too, and you ought to be in a DOMS free paradise.
Happy Practicing To You
Related Posts
- Delayed Onset Muscle Soreness (Part 1): What Is It and What Doesn't Work to reduce, attenuate or eliminate it
- Occlusion training: how to and why you might try it
- Does Cardio Interfere with Strength Training: How 'Bout No
- Lots more Perfusion: Review of Viking Warrior Conditioning
- What's a warm up and why do one?
- protein blends (with protease) for vegan and omnivore alike
Friday, July 24, 2009
Occlusion training: Sparking Muscle Growth when Injured or Just Sick of Heavy Loads
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When we hear the words "muscle hypertrophy" most of us think of body building and super duper muscle mass.
But hypertrophy itself is a natural and indeed necessary part of strength development. And it can be hard to induce hypertrophy when coming back from an injury or just when pooped of dealing with heavy weig Occlusion training (restricting venus return for very short periods) has intriguingly been associated with muscle hypertrophy. This recent review shows that its combined use with low loads can be great for rehab of ACL injuries as well as general athletic prep.
Great scott. Do you see capitol letters as shouting? this authors must be really excited about the research.
The part that is exciting is that if you can give a population a way to train their muscles and build their muscles at loads that are much lighter that what would be needed otherwise, you can imagine that the opportunities to get repair happening or growth happening could be, er, huge. Hypertrophy huge.
So let's take a quick peek at what hypertrophy is understood to be, and then at how occlusion training is generally applied.
Hypertrophy. Well, we know that if bodybuilders talk about hypertrophy they're talking about building muscle mass. But as said, anyone developing strength will get some hypertrophy happening. Why? How do we get stronger? That's complicated, but a simplified model would be: in the first instance, we are learning simply how to fire the muscles we have to do some new task, like lifting something heavy. So for someone who's never lifted, when starting a lifting program, say, they make big leaps in their strength in the first 8-12 weeks. A lot of that is neurological.
The other part of muscle building is laying down new muscle fibers to deal with trauma. When we train, we break down muscle tissue often deliberately in order to create an adaptation/growth. SO muscle literally gets pulled apart from time to time. Ironically, that is not what causes delayed onset muscle soreness (or DOMS). DOMS hits 24 - 48 hours after working out muscles (hence the delay part) and some theories are that it's the result of new muscle fibers butting up against each other and settling in - so it's the repair process rather than the damage process that is painful. Neat.
Which brings us to hypertrophy, in particular myofibrillated hypertrophy, which is the laying down of new actual muscle fibers or myofibrils. These are tiny fibers and not where the body builders' bulk comes from. That's generally sarcoplasmic - also important to protect the myofibrils and usually goes hand in hand with myofibrillated hypertrophy. We'll come back to that another time. Suffice it to say, what kind of growth is where sets, reps and REOCVERY come into play in terms of this balance and which kind of hypertrophy a program is privileging.
So let's say we're looking at getting the muscles around a knee injury built back up. The person is at a place where they can body squat, maybe do some light weight work, but (a) it may not be desireable for the person to do TONS of reps, but unless they do tons of reps with a light weight, desired hypertrophy - new muscle tissue growth - is not going to happen. Enter this really cool aspect of hypertrophy training, Occlusion training.
Likewise, OT *may* be useful to give athletes a break from high load work. Note, this does not mean do OT during a back off weak: the whole point of a back off weak is to let the body recover, not push it to adapt further.
Occlusion Training. Occlusion is a beautiful sounding word, isn't it? It's usually seen in visual contexts - to occlude something is to block it from view. If you put your mother's picture in front of that ugly stone someone gave you from their holiday in Crete, you have occluded the view of the offensive object that your loved ones won't let you chuck.
In occlusion training, we're talking about another kind of block. In this case, blocking the flow of blood - a bit, and for intervals. So what? How can that be good?
Well, an idea is, restricting blood flow causes fast twitch fibers to get involved in the process sooner than they otherwise would. Likewise a biggie in the effect is the production of blood by-products, and ones that trigger significant increases in GH. (i have visions now of Mike Mahler tying up his quads while doing lightweight kettlebell swings).
Caveats of Application. SO when we talk about restricting blood flow, what are we really talking about? IF we cut it off, don't our limbs drop off? Well, yes. So here, we're talking about restriction as opposed to total constriction, and also for particular intervals. And for light loads.
Ok what does that mean in practice? There are a variety of approaches described in the article that involve walking and the effects on strength. Pretty cool stuff. The authors, however, offer a sample protocol for strength:
from the article: note binding for knee work is at the top of the thigh - the proximal end of the vastus
The above is not encouragement to go try tying off your friend's legs and asking them to jump around :) As the authors state about future work:
Loenneke, J., & Pujol, T. (2009). The Use of Occlusion Training to Produce Muscle Hypertrophy Strength and Conditioning Journal, 31 (3), 77-84 DOI: 10.1519/SSC.0b013e3181a5a352 Tweet Follow @begin2dig
When we hear the words "muscle hypertrophy" most of us think of body building and super duper muscle mass.But hypertrophy itself is a natural and indeed necessary part of strength development. And it can be hard to induce hypertrophy when coming back from an injury or just when pooped of dealing with heavy weig Occlusion training (restricting venus return for very short periods) has intriguingly been associated with muscle hypertrophy. This recent review shows that its combined use with low loads can be great for rehab of ACL injuries as well as general athletic prep.
The Use of Occlusion Training to Produce Muscle Hypertrophy
Loenneke, Jeremy Paul BS; Pujol, Thomas Joseph EdD, CSCS
Strength and Conditioning Journal:
June 2009 - Volume 31 - Issue 3 - pp 77-84
doi: 10.1519/SSC.0b013e3181a5a352
Articles
LOW-INTENSITY OCCLUSION (50-100 MM HG) TRAINING PROVIDES A UNIQUE BENEFICIAL TRAINING MODE FOR PROMOTING MUSCLE HYPERTROPHY. TRAINING AT INTENSITIES AS LOW AS 20% 1 REPETITION MAXIMUM WITH MODERATE VASCULAR OCCLUSION RESULTS IN MUSCLE HYPERTROPHY IN AS LITTLE AS 3 WEEKS. A TYPICAL EXERCISE PRESCRIPTION CALLS FOR 3 TO 5 SETS TO VOLITIONAL FATIGUE WITH SHORT REST PERIODS. THE METABOLIC BUILDUP CAUSES POSITIVE PHYSIOLOGIC REACTIONS, SPECIFICALLY A RISE IN GROWTH HORMONE THAT IS HIGHER THAN LEVELS FOUND WITH HIGHER INTENSITIES. OCCLUSION TRAINING IS APPLICABLE FOR THOSE WHO ARE UNABLE TO SUSTAIN HIGH LOADS DUE TO JOINT PAIN, POSTOPERATIVE PATIENTS, CARDIAC REHABILITATION, ATHLETES WHO ARE UNLOADING, AND ASTRONAUTS.
Great scott. Do you see capitol letters as shouting? this authors must be really excited about the research.
The part that is exciting is that if you can give a population a way to train their muscles and build their muscles at loads that are much lighter that what would be needed otherwise, you can imagine that the opportunities to get repair happening or growth happening could be, er, huge. Hypertrophy huge.
So let's take a quick peek at what hypertrophy is understood to be, and then at how occlusion training is generally applied.
Hypertrophy. Well, we know that if bodybuilders talk about hypertrophy they're talking about building muscle mass. But as said, anyone developing strength will get some hypertrophy happening. Why? How do we get stronger? That's complicated, but a simplified model would be: in the first instance, we are learning simply how to fire the muscles we have to do some new task, like lifting something heavy. So for someone who's never lifted, when starting a lifting program, say, they make big leaps in their strength in the first 8-12 weeks. A lot of that is neurological.
The other part of muscle building is laying down new muscle fibers to deal with trauma. When we train, we break down muscle tissue often deliberately in order to create an adaptation/growth. SO muscle literally gets pulled apart from time to time. Ironically, that is not what causes delayed onset muscle soreness (or DOMS). DOMS hits 24 - 48 hours after working out muscles (hence the delay part) and some theories are that it's the result of new muscle fibers butting up against each other and settling in - so it's the repair process rather than the damage process that is painful. Neat.
Which brings us to hypertrophy, in particular myofibrillated hypertrophy, which is the laying down of new actual muscle fibers or myofibrils. These are tiny fibers and not where the body builders' bulk comes from. That's generally sarcoplasmic - also important to protect the myofibrils and usually goes hand in hand with myofibrillated hypertrophy. We'll come back to that another time. Suffice it to say, what kind of growth is where sets, reps and REOCVERY come into play in terms of this balance and which kind of hypertrophy a program is privileging.So let's say we're looking at getting the muscles around a knee injury built back up. The person is at a place where they can body squat, maybe do some light weight work, but (a) it may not be desireable for the person to do TONS of reps, but unless they do tons of reps with a light weight, desired hypertrophy - new muscle tissue growth - is not going to happen. Enter this really cool aspect of hypertrophy training, Occlusion training.
Likewise, OT *may* be useful to give athletes a break from high load work. Note, this does not mean do OT during a back off weak: the whole point of a back off weak is to let the body recover, not push it to adapt further.
Occlusion Training. Occlusion is a beautiful sounding word, isn't it? It's usually seen in visual contexts - to occlude something is to block it from view. If you put your mother's picture in front of that ugly stone someone gave you from their holiday in Crete, you have occluded the view of the offensive object that your loved ones won't let you chuck.
In occlusion training, we're talking about another kind of block. In this case, blocking the flow of blood - a bit, and for intervals. So what? How can that be good?
Well, an idea is, restricting blood flow causes fast twitch fibers to get involved in the process sooner than they otherwise would. Likewise a biggie in the effect is the production of blood by-products, and ones that trigger significant increases in GH. (i have visions now of Mike Mahler tying up his quads while doing lightweight kettlebell swings).
Caveats of Application. SO when we talk about restricting blood flow, what are we really talking about? IF we cut it off, don't our limbs drop off? Well, yes. So here, we're talking about restriction as opposed to total constriction, and also for particular intervals. And for light loads.
Ok what does that mean in practice? There are a variety of approaches described in the article that involve walking and the effects on strength. Pretty cool stuff. The authors, however, offer a sample protocol for strength:
A typical low-intensity prescription would involve an intensity of 20-50% of 1RM with a 2-second cadence for both the concentric and eccentric actions. The 1RM is calculated from the maximum amount of weight you can lift once under normal blood flow conditions. Three to five sets of each exercise are completed to volitional fatigue. This is done to ensure that there is a high metabolic buildup. The rest periods are 30 seconds to 1 minute in length and occur between every set, with the occlusion still being applied (5,6,27,35,36,39). At the conclusion of the last set, blood flow is restored to the muscle.Again, the important take away here is LIGHT loads for a few sets. Likewise the PROXIMAL end of the targetted muscle is what gets bound, as shown in the image below.
Cook et al. (6) compared different protocols of occlusion using percent maximal voluntary contraction (%MVC) and found that 20% MVC with continuous partial occlusion was the only protocol that elicited significantly more fatigue than the higher intensity protocol.
from the article: note binding for knee work is at the top of the thigh - the proximal end of the vastusThe above is not encouragement to go try tying off your friend's legs and asking them to jump around :) As the authors state about future work:
Future research on occlusion training should focus on studying the health risks associated with long-term use and determine populations in which this type of training may be contraindicated (6). Although the research has yet to define populations in which occlusion training is dangerous, we postulate that those with endothelial dysfunction should not use occlusion training because of the reduction in blood flow. Research should also further study the microdamage to blood vessels and subtle changes in blood flow, both of which may stimulate thrombosis (38). Also, one should seek to evaluate the gene expression at later stages of postexercise recovery after occlusion and in response to occlusion training (7). Finally, studies should begin to focus on the local regulators of muscular growth, such as growth factors and reactive oxygen species, to elucidate the mechanism for the present cooperative effects of exercise and occlusive stimuli (39).Take away: if you're looking to build up strength especially after an injury, short term use of occlusion training may be a good way to get back in the game. Likewise, if you're getting fatigued by heavy lifting or jus the thought of having to pick up a really heavy bar to make a difference is getting you down, doing some short term occulsion sets because of their effective LOW reps and LIGHT weight, may be just the thing to keep you training and provide the mental break necessary to get back at it.
Loenneke, J., & Pujol, T. (2009). The Use of Occlusion Training to Produce Muscle Hypertrophy Strength and Conditioning Journal, 31 (3), 77-84 DOI: 10.1519/SSC.0b013e3181a5a352 Tweet Follow @begin2dig
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