Friday, July 31, 2009
Last year when talking about the difference between cradio and vo2max training and the benefits thereof, especially for enhancing mitochondrial density, the stuff that makes fat burn in the cells, i mentioned this pretty new research out of (happiness and joy) Canada:
Here's the abstract
Low-volume 'sprint' interval training (SIT) stimulates rapid improvements in muscle oxidative capacity that are comparable to levels reached following traditional endurance training (ET) but no study has examined metabolic adaptations during exercise after these different training strategies. We hypothesized that SIT and ET would induce similar adaptations in markers of skeletal muscle carbohydrate (CHO) and lipid metabolism and metabolic control during exercise despite large differences in training volume and time commitment. Active but untrained subjects (23 ± 1 years) performed a constant-load cycling challenge (1 h at 65% of peak oxygen uptake before and after 6 weeks of either SIT or ET (n= 5 men and 5 women per group). SIT consisted of four to six repeats of a 30 s 'all out' Wingate Test (mean power output ∼500 W) with 4.5 min recovery between repeats, 3 days per week. ET consisted of 40–60 min of continuous cycling at a workload that elicited ∼65% (mean power output ∼150 W) per day, 5 days per week. Weekly time commitment (∼1.5 versus∼4.5 h) and total training volume (∼225 versus∼2250 kJ weekOn the face of it, the big take away from the study, as the authors say themselves in the Discussion part of the article: the effect on carbs in the muscle and fat metabolism were comparable to the endurance training protocols, and here's the kicker
−1) were substantially lower in SIT versus ET. Despite these differences, both protocols induced similar increases
Similar metabolic adaptations during exercise after low volume sprint interval and traditional endurance training in humans
Kirsten A. Burgomaster, Krista R. Howarth, Stuart M. Phillips, Mark Rakobowchuk, Maureen J. MacDonald, Sean L. McGee, Martin J. Gibala
Published Online: Jan 2 2008 12:00AM
quick note on terms: vo2peak is highest VO2 elicited in test to exhaustion; the more familiar vo2max which is the plateau hit for V02 when adding progressive load. So you can readily hit vo2max before exhaustion.
despite a much lower training volume and time commitment. By design, weekly training volume was ∼90% lower in the SIT group (∼225 versus∼2250 kJ week90% lower! in terms of time and effort. So, low volume (few repeats) of maximal effort with good recovery has the same effect as high volume mid intenstity.
−1for ET) and necessitated a training time commitment that was only ∼one-third of that of the ET group (∼1.5 versus 4.5 h [over 6 weeks -mc]).
Now some folks may say ya ya, we know intervals are more efficient at burning calories than lower intensity steady state: more effort you burn more. Duh. But calories burned is not the big exciting part of this story. It's the mitochondria and the carbohydrates that are kinda amazing.
Getting Endurance Effects from Resistance Like Training?
One of the big reasons people blend HIIT with steady state lower intensity (65%) cardio training is both for (1) elasticity of heart muscle health that say resistance training alone doesn't give (pick up Kenneth Jay's Viking Warrior Conditioning for more on this) and/or (2) creating cells that are better fat burners. Aerobic workouts both privilege fat as the fuel of choice AND they enhance the qualities of cells (mitochondria) that get fat oxidized (burned) for fuel.
Folks in the house who use kettlebells may be getting all smug here by saying that doing lots of swings with a mid sized bell does the endurance work, while all their presses, pulls and snatches takes care of the power/resistance stuff. Yes, it's a magic ball!
The thing is, again, the powerful finding of this work, is that it shows that that all important, highly sought-after mitochondria proliferation is occurring in super intense work in a way comparable to that 65% endurance work. That's not what we're doing in a ten minute swing set with a kb. And that's just not what would be predicted in the normal model of our metabolism. And here's why i love good science: the authors admit as much by saying they don't know why they are getting these results, citing that traditional and current understanding of strength/endurance
In other words (i love good science, did i say that?) given what we've understood about how our bodies work, these results shouldn't happen (and this is the second time the authors have repeated these results - in fact that they're getting similar effects in this 6 week trial as they did in their 2 week trial is provocative in itself).
While the present study demonstrates the potency of SIT [sprint interval training -mc] to elicit changes in muscle oxidative capacity and selected metabolic adjustments during exercise that resemble ET [endurance training -mc], the underlying mechanisms are unclear. From a cell signalling perspective, exercise is typically classified as either 'strength' or 'endurance', with short-duration, high-intensity work usually associated with increased skeletal muscle mass, and prolonged, low- to moderate-intensity work associated with increased mitochondrial mass and oxidative enzyme activity (Baar, 2006).
In other words the 02 deficit may be SO HIGH after this effort your body may up-regulate O2 consumption afterwards, which impacts the aerobic system. So it might be the rest intervals during and post the effort where the aerobic ET-like adaptation is occurring.
What does that mean? Time to update the model - and consider all the variables that may play a role, from the brevity of the interval (longer may be counter-productive) to an understanding of the recovery period processes. The authors speculate that part of the answer is that the intensity of effort turns on a particular gene expression PGC-1α due to a whole bunch of upregulated muscular related fuel events that we'll skip here but that are triggered by this kind of intensity burst.
Indeed, in a study by Gibala that came out just this past June, 2009, the author came back to some of these questions. And that transcripter seems to be a winner. The abstract reads, in part,
A key controller of oxidative enzyme expression in skeletal muscle is peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha), a transcriptional coactivator that serves to coordinate mitochondrial biogenesis...Signaling through AMP-activated protein kinase and p38 mitogen-activated protein kinase to PGC-1alpha may therefore explain, in part, the metabolic remodeling induced by HIT, including mitochondrial biogenesis and an increased capacity for glucose and fatty acid oxidation.The conclusion comes away saying that this KIND (and potentially duration) of interval has magical properties that blend endurance benefits for mitochondria building while being what looks like resistance training:
High-intensity interval exercise represents a unique and understudied model for examining the molecular regulation of skeletal muscle remodeling. Like strength or resistance training, interval exercise is characterized by brief intermit- tent bouts of relatively intense muscle contraction. However, interval exercise training induces phenotypic changes that resemble those elicited after traditional endurance training. Preliminary evidence suggests that signaling through AMPK and p38 MAPK to PGC-1a may explain, in part, the meta- bolic adaptations induced by HIT, including mitochondrial biogenesis and an increased capacity for glucose and fatty acid oxidation.In other words, turning on PGC-1a is a big deal to generating this remodeling. And we know from the other studies - or at least strongly suspect - that it's hitting high intensity for these short blasts that does the turning on.
Carbohydrate AND Phosphocreatine Sparing? What's new?
But let's come back to the other big finding of this study - less sensational, but good to confirm:
The usual model is that, going anaerobic - which an all out sprint effort does - means that we burn fuel from the phosphagen system in the initial blast and then we hit carbs. Phosphagen gives us a small burn of 10-30secs. After that, carbs kick in for about another three minutes of burn. Important to note is that we mean these are the primary fuel systems - oxygen (and so some fat burning) is always working too or we'd croak.
Part of the reason folks do vo2max training is to be carbohydrate sparing - we want to make the body able to use oxygen for greater levels of work, so that it turns to carbs at only higher and higher demands for fuel. Why would we want to do this? Two reasons: we have way more fat available for fuel than we do carbs, and fat gives way more energy bang for the buck than do carbs. In other words we can go longer on a gram of fat than we can a gram of carbs.
If you're doing weight loss work, naturally getting fat burning optimized is a good thing. This effect is again why folks traditionally do lower intensity cardio: it privileges fat burning for fuel.
Likewise in the strength training space, the reason we supplement with creatine is to help keep the phosphagen system topped up - so we can get a few more reps in at that higher phosphogen level fuel system going.
Now here's a protocol that says it's both beneficial for phosphocreatine and carbohydrate sparing. THat's not surprising for interval training to claim. That's part of the reason, as said, we do that with resistance work to develop power, and with vo2max work for higher endurance. The kicker here is the achievement of same with very low volume.
Here's how they tested it: they tested their SIT and ET groups prior to the study commencing with a 65% of pre-training v02peak effort of cycling for an hour. They did the same thing after 6 weeks. The researchers found again comparable changes in fuel usage in both groups so there were both carb and phosocreatine benefits from super low volume training.
The results may not be cost free, but the cost may be minimal or negligible. The amount of ATP at rest in the SIT group was lower; it didn't change in the ET group. This means that amount of available material to be used for muscle contraction was lower in the SIT group. The researchers aren't sure why this was the case: it takes awhile to reamp ATP and it may just be from residual effects of the last excercise bout before the samples were taken, or it may be an effect of the chronic excercise protocol. Not sure. Dunno. Watch that space.
So finally we can dump aerobics/cardio training?
If we get all the tasty goodness of aerobic trad endurance training from these brief moments of vomitus activity, can we skip cardio entirely? Answer: we don't know (did i say i love science yet?)
It is also important to stress that the relatively limited array of metabolic measurements performed in the present study may not be representative of other physiological adaptations normally associated with ET. For example, SIT may differ from ET with respect to changes induced in the cardiovascular and respiratory systems, metabolic control in other organs (e.g. liver or adipose tissue) and protection from various factors associated with chronic inactivity (e.g. insulin resistance or lipid dysregulation).Indeed, with respect to the all important insulin, and the goal of building insulin sensitivity, in another June 09 publication, Hawley and Gibala look at insulin intensity and exercise intensity and ask "how low can you go?" The authors wanted to get as close as current research findings, when synthesized, might suggest, how *intense* does exercise need to be to have a beneficial effect on insulin sensitivity. Conclusions so far?
It remains to be determined whether high-intensity, low-volume interval training protocols can confer all of the health-related benefits associated with less intense, more prolonged traditional endurance training programmes. [Based on the review of literature to date, however -mc] it seems prudent to recommend that, for patients with insulin resistance or type 2 diabetes, the minimal dose of physical activity needed to maintain or improve health is equivalent to ~4,000 kJ/week of low- to moderate-intensity exercise. However, for patients who only show modest improvements in clinical and metabolic outcomes at this level of activity-induced energy expenditure, an increase in the intensity of exercise may be considered because of the potential additional benefits in both metabolic control and cardiorespiratory fitness.In other words going all out with sprint intervals is not for everyone or all conditions.
Is Even Less Even More?
Likewise, the current study measured 30s intervals for 6 mins of work. In a recent interview, Gibala said an upcoming study for fall 2009 will look at how low those intervals can go for benefit. Could a single two or three minute bout be as effective as those six minutes? Dunno!
A few Points on Gear.
I sense the kettlebeller within immediately wanting to give this protocol a go with kb snatching or some such. An important note, then.
The study was carried out on a stationary bike. That's the typical device for a wingate test. It's safe. Swimming is another safe place (no pounding for all those repeats) where one can get one's heart and system up to that intensity - though swimming is harder to gate. Easier on a bike.
The wingate test is a precisely set load on the individual: from .075kg/kg of athlete to 1.3kg/kg of athlete. It would be interesting to think about how to translate this kind of resistance to a *safe* kettlebell routine.
Of course the disadvantage of thinking about such a rep set might be that one's form goes to hell, and that's totally wrong, engraining poor rep quality is rather problematic neurologically not always to be going for a perfect rep.
A few questions about fitness and body comp
Most of us workout because we want to be strong and look half decent half dressed. What this study did not measure is what these results mean for the technical body comp (bf%, say) and the visual body comp (dress size, look in the mirror, buff-ness).
For instance, in a study from 2007, it seemed that for folks to maintain their desired body look and feel, they needed to workout for 5 hours a week, mixing up cardio, intervals and strength work.
Now while this study protocol hasn't been put forward as a training program that's sorta where the NYT interview, cited above, was coming from, and it's certaininly an interest of the folks doing the studies.
But the question might be, given body comp and strength goals, what would this 6 mins a week fitness regine get those of us who are, well, already fit enough to contemplate it?
Part II: What does this all really mean for our actual real workouts? 6 plain language take aways, next.
Burgomaster, K., Howarth, K., Phillips, S., Rakobowchuk, M., MacDonald, M., McGee, S., & Gibala, M. (2007). Similar metabolic adaptations during exercise after low volume sprint interval and traditional endurance training in humans The Journal of Physiology, 586 (1), 151-160 DOI: 10.1113/jphysiol.2007.142109 Tweet Follow @begin2dig
Tuesday, July 28, 2009
Most of us would say "body comp" means weight, girth measures, bmi changes. But no. It doesn't. In this case, it seems to mean fat kids who worked out got stronger, added lean mass, but didn't lose weight or overall fat. This is consistent with other studies of working out without diet to go with it:
McGuigan, MR, Tatasciore, M, Newton, RU, and Pettigrew, S. Eight weeks of resistance training can significantly alter body composition in children who are overweight or obese. J Strength Cond Res 23(1): 80-85, 2009-Update: as R.M. Koske rightly points out in the comments below, body comp is technically changes in fat/muscle/bone ratios. And it's not entirely fair to conflate a scientific definition of a concept used in a research journal with popular understanding. But i DO take issue with the term SIGNIFICANT body comp alteration. more on that below.
The purpose of this study was to investigate the effect of an 8-week resistance training program on children who were overweight or obese. Forty-eight children (n = 26 girls and 22 boys; mean age = 9.7 years) participated in an 8-week undulating periodized resistance training program for 3 d[middle dot]wk-1. Measures of body composition via dual-energy X-ray absorptiometry, anthropometry, strength, and power were made before and after the training intervention. There was a significant decrease in absolute percent body fat of 2.6% (p = 0.003) and a significant increase in lean body mass of 5.3% (p = 0.07). There were no significant changes in height, weight, body mass index, total fat mass, or bone mineral content. There were significant increases in 1-repetition maximum squat (74%), number of push-ups (85%), countermovement jump height (8%), static jump height (4%), and power (16%). These results demonstrate that the resistance training program implemented produces significant changes in body composition and strength and power measures, as well as being well tolerated by the participants. An undulating periodized program provides variation and significantly increases lean body mass, decreases percent body fat, and increases strength and power in children who are overweight and obese.
First off, the main goal of the study was to explore resistance training rather than aerobic intervals training for obese kids. As far as i can tell, they are simply hypothesizing that some kids who are obese may prefer lifting to running type activities, and if that's the case, let's see what that does. That's not much of an hypothesis to test in a research environment is it?
Not surprisingly, since other research has shown this too, obese kids in an 8 week program make super strength and power gains too. Just like non-obese kids. And like adults of all ages who are new to lifting. Neural adaptations are taking place, and new tissue is being laid down.
Now the authors claim that their findings are great. They say
An undulating periodized program provides variation and results in significant increases in lean body mass, decreased percent body fat, and increased strength and power.
It's really great to see BMC going up too - that's something to keep for life.
But where does this take us? IF absolute fat doesn't go down, weight goes up, how does bf% go down? There's more new lean mass. as opposed to more (or less) fat. That's kinda fudging, isn't it?
These results (gaining lean mass; not losing weight overall) are consistent with both non-obese kids and adults. It tells us that muscle building mechanisms for the first 8 weeks of a program have an impact. That's good. What about the next 8 weeks and then the next 48 weeks?
When we work with adults who are overweight, we know that after 8-12 weeks, if their girth, weight, and fat - nothing on these measures seems to change - they are not feeling a whole lot of love and success or seeing it in their mirrors.
We know that the study reports here that eating habits didn't change throughout the study. They weren't logged too religiously, though, and unless an observer is making those logs, we know from other work that we ALL misreport food logs.
We know that folks may feel zippier from working out - and that's fabulous - but we also know with obese adults that without nutrition, all the jumping and pumping in the world will not shed the excess weight which is having the biggest negative impact on overall health.
What's the Point? In fairness, one might say, this study was *just* looking at effects of resistance training over 8weeks on obese kids. Is that good enough? These are real kids with real problems. Is this fair to them or the best we can do?
Consider this: the study doesn't explicitly state an hypothesis, eg: we postulate that fat kids who do resistance will have the same benefits as non-fat kids who start resistance.
Is that poor science not to have an explicit hypothesis? Generally speaking, in most fields, yes.
Because you have to defend why you hypothesize your position and show value of the study: why on earth would you think you'd need to see if fat kids respond to resistance training differently than skinny kids? When that's said outloud, kinda makes one go "hmm" no?
Without that rationale for the study being clear, what's the point of the work? It's rather gratuitous. The authors as said only suggest that some fat kids might not like aerobics or intervals so they need alternatives. Right! so the next point would be again to say, we have lots of results to show the benefits of resistance training for kids. What's the special thing you think you need to test in this population not covered by these other studies?
Well, these kids are obese.
Ok, so what? are you asserting that because of that, the effects of a resistance program may be different? if so why? what's the basis for that assertion and how will you test it? Are there special fat kid risk factors to test that one might think fat kids shouldn't do resistance? No? So what's the point?
The authors just show what we already know from a zillion ways past sunday: resistance training builds lean muscle. And even if absolute fat doesn't go down, because lean muscle goes up, the bf% ratio changes. And as we see in the charts, kids did gain weight - from the lean muscle.
That's why these kind of studies seem gratuitous to me. And heh, not every paper an academic writes is earth shattering. But something leaves me edgy here. Obesity is a real problem. This study is dealing with clinically overweight and obese kids (over 23-43% body fat in the study).
So we've confirmed that yet one more population benefits from resistance training. Was there any doubt, however, that that would be the case? Any hypothesis to test? No? then what's the study contributed, really? For 8 weeks kids got no nutritional counseling when the authors KNOW that obesity programs combine nutrition and exercise. "It is clear that, along with nutrition and lifestyle, exercise plays a significant role in overcoming obesity in children."
But if the authors had provided that counseling, that would have screwed up their results: they wouldn't know what was down to resistance vs what was down to diet.
Now ethically, we can say the children weren't harmed; in fact they are healthier than when they started. And still obese. And if they stick with their current training and their current activity they'll still be obese a year from now.
What's actually been proven here? hypothesis testing two. In the realm of statistics, one can simply set an alpha or confidence level - a percentage - by which if the results fall within that percentage, the results happened because of the intervention, not by chance. The way the authors set up this study, their signficance values don't claim that the body comp change is significant, but that the reason for the change is down to the intervention. That's right. Just that what change occurred is not because of chance but because of the progam. In other words they have an above 95% certainty that that body comp change is because of the training. Shocking.
Ok, that's not shocking but it means the title is: Eight weeks of resistance training can significantly alter body composition in children who are overweight or obese. All that can be claimed, surely, is that we know within the realm of probability, literally, that resistance training has an effect at changing body comp. To say a "significant" effect - again means kinda weasel words. In stats, significance just means there's a treatment effect. To normal human beings significant means "wow that was a big deal."
So the authors are being technically accurate, but less clear that perhaps saying "Resistance training does induce body comp changes in fat kids in 8 week protocol, really really"
So, bottom line, did we learn anything new from this study that we didn't know before? Are the results surprising in any way? Was a bold hypothesis demonstrated? Did researchers who know that nutrition and lifestyle along with exercise is a big part of dealing with obesity provide that information to their participants' families as part of the study or just say good bye to the participants at the end of the 8-weeks?
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Turns out, at least for young men who haven't done creatine before, that doing *some* creatine supplementation makes a difference in terms of preserving lean tissue in the upper limbs.
Johnston, APW, Burke, DG, MacNeil, LG, and Candow, DG. Effect of creatine supplementation during cast-induced immobilization on the preservation of muscle mass, strength, and endurance. J Strength Cond Res 23(1): 116-120, 2009-
Muscle and strength loss will occur during periods of physical inactivity and immobilization. Creatine supplementation may have a favorable effect on muscle mass and strength independently of exercise. The purpose of this study was to determine the effects of creatine supplementation on upper-limb muscle mass and muscle performance after immobilization. Before the study, creatine-naive men (n = 7; 18-25 years) were assessed for lean tissue mass (dual-energy X-ray absorptiometry), strength (1-repetition maximum [1RM] isometric single arm elbow flexion/extension), and muscle endurance (maximum number of single-arm isokinetic elbow flexion/extension repetitions at 60% 1RM). After baseline measures, subjects had their dominant or nondominant (random assignment) upper limb immobilized (long arm plaster cast) at 90[degrees] elbow flexion. Using a single-blind crossover design, subjects received placebo (maltodextrin; 4 x 5 g[middle dot]d-1) during days 1-7 and creatine (4 x 5 g[middle dot]d-1) during days 15-21. The cast was removed during days 8-14 and 22-29. The dependent measures of lean tissue mass, strength, and endurance were assessed at baseline, postcast, and after the study. During immobilization, compared with isocaloric placebo, creatine supplementation better maintained lean tissue mass (Cr +0.9% vs. PLA -3.7%, p
The authors caution that results by others of testing lower limb immobilization has not found these results. They wonder if it's the ratio of fiber types in the upper limbs or other factors that show these results. Suffice it to say, if you find yourself in an arm cast, you may want to consider trying some creatine to reduce "myoplastic changes directly related to disuse atrophy, thereby facilitating the rehabilitation process."
Just be sure to get a good quality creatine :) Tweet Follow @begin2dig
Monday, July 27, 2009
Rannoch's 100s (R100s): the unWorkout that Refreshes, repairs and prepares the embodied soul for work
300 is so 2007. 100 is where it's at.
Awhile ago Rannoch was telling me about his philosophy of getting 100 reps in a day of something. Doesn't matter what. Just get 'em in.
Now at the time i thought that was way cool, and as i have a variety of kettlebells around me at work and home, i started doing 100's of light snatches. That sorta faded from my view for awhile traveling, but in terms of coming back to some serious preparatory training, and feeling kinda down on myself for being deconditioned, i thought about Rannoch's 100's and thought well at least i can start there.
This was a new way of thinking about using the 100's as pump priming.
So i got a 100 out of the way with one weight.
And i felt better.
That was something when i didn't think i was going to have time then for anything.
That's a start; that's a foundation.
That's a few minutes of work i wouldn't have had before a morning shower.
So after a cup of tea, i did another 100. heavier. harder. stinkier
Aside: The pause that refreshes (when the unpause is stupid). When my hand was feeling a little raw on the bell i did something i usually don't let myself do: i put the bell down for a sec and did not feel like a failure or loser for taking a break 25 reps in to go find the chalk. I chalked. And continued. Who said it had to be non-stop every time? Maybe tomorrow it will be. Today i needed chalk - and am i glad i did or there would not be a tomorrow. (I put the ability to take a break down to intense work on getting rid of crap around goals -but that's another story)
So i got in two blocks of non-threatening-to-my-cns-first-thing-in-the-am, happy R100's before the morning shower. First one, gentle reminder with some effort in endurance; the second one more work overall. Good.
Threat Modulation value of 100's
One might say well hell that's not working out, that's not serious. that's nothing.
Well it sure as heck is greasing the neurological groove. Reminding my body about the time it takes to get in 100 consecutive perfect snatches; looking to keep that under 5 mins. Letting my body know what it feels like to find the flow of that movement. Then taking it up a notch. Still feeling safe. Letting myself get chalk to protect my hands - and so feeling safe and those reps were better. And getting in volume on a move. The perfect rep is still the perfect rep.
Those 100s then have great psychological benefit, and what's really cool, considerable neurological benefit, to let my brain, the body and their connective cns tissue work together well and get ready for the Great Work to Come.
Preparation vs A Plan of Action: 100's as the unpsych psych
As said, i'm getting ready to do some serious training. Talking about "getting ready to do some serious training" is a rather newish concept for me anything outside seasonal macro cycles for Strength and Conditioning athletes for pre during and post season training.
What i'm talking about with Preparation is the prep to get into the training i know i need to do for a particular training goal that has a specific date attached to it. What i've learned in the nutrition context and work in the habit-changing context is that when we're introducing a new behaviour (and new can be relative) we often fail because we leap into action without having a plan of how we'll deal with stuff around the action.
For me right now i know that if i try to leap into a heavy training regime some part of me will balk: i need to revise my wake up times and all the rest of it.
So Rannoch's 100's around all the moves i'll need to practice are great ways for me to prepare for the work to come; to get the conversation with my brain and body happening to make the coming 6 months effective, injury free and why not fun?
Non Excercise Physical Activity is Good Too. If you don't need R100's for your prep, that's cool. You may want to consider them as a little extra daily grit like the value of NEPA's. They're great for that too. just super in fact.
What are R100's then?
Rannoch's exact definition may be different, but my sense of them is as something pretty low threat, easy to focus on form, with some at least NEPA value to them.
Likely 100 consecutive whatevers is the goal.
If it's so intense as to require (a) breaks for recovery mid 100's or (b) a do or die requirement for a shower after said 100 cuz you stink beyond what's fit for polite company - it may just be too intense for what we're describing.
Now my second set of 100's today did not pass that later shower requirement test. Do i care? no. i wanted to get some effortfulness in. And the first R100 made that happen. ya hoo.
Hope you'll give some r100's a go - especially if you're a little freaked out about getting into an intense workout regime or if you can't think of where you'll get your workout in today. What's 100 of something you know you can do? Tweet Follow @begin2dig
Fischer, Jennifer; Van Lunen, Bonnie L; Branch, J David; Pirone, Jamie L
The Journal of Strength & Conditioning Research. 23(1):44-50, January 2009.
This study examined the immediate and short-term (20 minute) effects of 3- and 10-minute ice bag applications to the hamstrings on functional performance as measured by the cocontraction test, shuttle run, and single-leg vertical jump. Forty-two (25 women, 17 men) recreational or collegiate athletes who were free of injury in the lower extremity 6 months before testing and who did not suffer from allergy to cryotherapy were included. Time to completion was measured in seconds for the cocontraction and the shuttle run test. Single-leg vertical jump was measured on the Vertec (Sports Imports, Columbus, Ohio) in centimeters. The 10-minute ice bag application reduced immediate postapplication vertical jump performance and increased immediate post and 20-minute post shuttle run time (p <= 0.05). A decrease in cocontraction time was observed at 20 minutes post compared with preapplication during the control condition in which no ice bag was applied. Power and functional performance are affected by short-term cryotherapy application. Power and functional performance was impaired immediately and 20 minutes after 10-minute ice bag application to the hamstrings, whereas a shorter duration of ice application had no effect on these tasks.
Right. Really, this result can't be seen as much of a surprise, so why did this study get published - publication of work generally means there's deemed to be a "significant contribution" to the field by the work presented
Aside: why ice? Turns out that RICE is being debated. While lots of good things have been claimed about icing, and there's literature that says, even though we don't know why, icing works better with compression, (er, maybe it's just the compression) some folks have been wondering if compression and ice are really great ideas rather than not interfering with the body's natural injury healing mechanisms. What about heat instead? what about no restriction on the area? what about compression rather than cold? what about letting the body just do it's thing?
A recent summary in 2007 by JL McDonald called Fire and Ice (pdf) states:
When the evidence to support the use of ice in musculoskeletal disorders is separated out from the commonly used context of the RICE (Rest, Ice, Compression, Elevation) protocol, it has been claimed that ice alone is effective in relieving pain, reducing oedema and relieving muscle spasm.I mean, folks make it sound so obvious: use ice (and elevation and compression) to bring down swelling, not heat because
• The evidence suggests that ice alone has a local anaesthetic [cuts off sensation -mc] rather than analgesic effect [actually acts on pain signals -mc].
• There is contradictory evidence for whether or not ice alone can reduce oedema [tissue swelling - mc] , but it may be that compression is the most effective component of the RICE protocol for oedema, given that, while compression is effective in reducing oedema, the addition of ice to compression shows no additional benefit.
• No evidence was found in the reviewed literature to support the assertion that ice can relieve muscle spasm, although there is consensus in the research that local heat can.
Heat is not your friend at first, because it increases circulation, which puts painful pressure on nerve endings. The warmth stimulates the flow of inflammatory chemicals, too, which make pain worse.Ok, pain is not necessarily a good thing, but if stimulating the flow of inflammatory chemicals is bad (is it? isn't inflammation an essential first part of healing? but ok, more is not always better) - what's the deal with trying to cut off that process with ice? what's ice doing in this kind of tissue condition where only ice is used? It doesn't bring down swelling - that's compression, apparently; it doesn't mitigate pain chemistry; it doesn't calm down spasaming muscles. What's left is that it anesthetizes the pain response so the sensation in the area goes numb.
No wonder researchers are worried about someone being iced up going back into play: they aren't feeling their limbs properly and spatial awareness would go south. The authors only hint at this being their concern:
In addition to the potential risk of injury [?? is it proprioception/senstation being deadened? -mc], the effect of cryotherapy on functional performance is a relevant concern, especially if the athlete plans to return to practice or competition immediately after the treatment.These authors are not the first to be concerned with the effects of icing prior to athletic endeavor. They site over a dozen studies that have come up with conflicting results about its impact on performance.
But wait. Aren't you hurt if you're icing?
What is interesting to me anyway, here, is that we're dealing with an athlete who has an injury, or they wouldn't be getting iced, and the question is what effect will icing have on their vertical jump? Ok, we're testing with un-injured participants, that's one (ethics and all but who's to say the effects are the same with someone with an injury), but isn't there a sort of fundamental ethical conundrum about asking someone who is so f'd up that they need to be icing in the first place then to go back into the game? The authors write in their Discussion section
Our study provides additional insight regarding the effect of cryotherapy on a major muscle group while performing functional activities. We wanted to provide clinical relevance to practicing certified athletic trainers; hence, we chose ice bag application because it is the most widely available form of cryotherapy. The time of application also coincides with the clinical relevance of the study. Our rationale for this includes circumstances in which the athlete will be returned to play after ice treatment of short durations. In some instances, an athlete will remove the ice bag early (within 10 minutes) and return him- or herself to play without clearance by a certified athletic trainer. We also examined the effect of these ice treatments after 20 minutes of time had elapsed; we found that as little as 10 minutes of ice can still detrimentally affect functional performance, as shown by the shuttle run in our study.I guess other questions would be, so what? We now know that three minutes has no impact on power, but ten minutes does. But isn't the question about the status of the injury? not about the overall minimal effect on power? What's the likelihood that with that slowed down effect that they'll reinjure themselves or be better protected? That doesn't get discussed.
What the others do note in practical applications is
Certified athletic trainers, athletes, coaches, and practitioners often apply ice to an injured athlete during practice or games. There are often times when athletes feel that they are ready to go back into competition, and they do not complete the total application time for the cryotherapy session. Our findings suggest that a 3-minute application does not affect the functional test measures, but a 10-minute application affects vertical jump and shuttle run times. An athlete may not be able to perform at his or her optimal level after a 10-minute application of cryotherapy even though the cryotherapy was applied to a secondary muscle group; therefore, we should use caution in returning the individual back into competition because there may be other deficits that have not yet been identified. Further research is warranted on primary muscle groups and on the use of short-term cryotherapy applications.
What are the authors saying? 10 mins may impact their performance so ten minutes is too long? But while three mins doesn't that's ok, send them back in? The authors leave the question hanging as to whether three mins. of icing, has that had a good effect, though, at all.
Or *maybe* the whole idea is stupid?
Here's my question: why does the athlete need to be iced? - assuming icing is in any way a good idea.
Here's the follow up questions:
If someone has such a degree of pain or inflammation that they need to be iced, what evidence is there to suggest that a three minute shot of ice has made the tissue situation sufficiently ok to enable a full re-introduction back into play in the first place?
Now maybe there is super evidence to support this: that staying moving is a good idea. There's tons of work in pain that pain does not equal injury, but let's say there is an injury, what are we doing here with the ice bag? Where is the work that shows in cases such as these - the athlete keen to get back in the game - that that's been a Wise Move in and of itself?
As said, there may be, and maybe that literature is so well known the authors haven't felt the need to site it, but that that issue doesn't even get a mention makes me think, maybe not. Tweet Follow @begin2dig
Saturday, July 25, 2009
At the recent Z-Health 9S:sustenance course, overviewed here, we talked a lot about supplements: about what ones are worth taking, yes, but also about where to source them, once you've made the decision to use them. Based on that discussion, i did some further digging. It's not a story with a happy ending. Sorta more like left who's on stage at the end of Richard III: oh goodie the exciting, poetic, smart villain is dead, while this cheating asshole is left to run the kingdom but at least no one will be fighting anymore. hoo frickin' rah.
So this post presents a brief overview of legislation in the US around dietary supplements, problems with supplement quality and contamination, what good manufacturing practice (aka cGMP is) what third party certification like Consumer Labs or USP does with GMP (overivewed, anyway), a glimpse at the EU situation, and why June2010 is not the end of the War of the Roses.
History and Current Unregulated Practice. In the US, since 1994, there's been no requirement to have the Food and Drug Administration (FDA) assess either what goes into supplements or how they're made. Indeed, the FDA explicitly does NOT certify supplements (the way it does drugs and biologics). As its own web site says:
FDA does not approve dietary supplements.Why might such oversight at the level of the FDA be important? Well, our fave sup companies might not be delivering the goods. Consider this story from June this year on a consumerlabs.com test of various supplements:
Unlike new drugs, dietary supplements are not reviewed and approved by FDA based on their safety and effectiveness. Most dietary supplements that contain a new dietary ingredient (a dietary ingredient not marketed in the United States before October 15, 1994) require a notification to FDA 75 days before marketing.
The notification must include the information that was the manufacturer or distributor's basis for concluding that the dietary supplement will reasonably be expected to be safe. After dietary supplements are on the market, FDA evaluates their safety through research and adverse event monitoring.
Potency problemsIn ConsumerLab.com testing last November, four out of seven supplements contained less ginkgo than claimed on their labels, and one failed to break apart properly to release its ingredients. Seven out of nine failed in tests in 2003, as did six out of 13 in 2005."It is now believed that ginkgo is among the most adulterated herbs," the company reports.Tests by California scientists of two dozen ginseng supplements, reported in a nutrition journal in 2001, found that many differed from their labels. The concentrations of some ginseng compounds varied by up to 200-fold from product to product.In ConsumerLab.com tests, six out of nine chondroitin supplements failed testing in April 2007. One had only 8 percent of what it claimed to contain, and one "maximum strength" product had none.
Vitamins and minerals had problems, too. A "high potency" iron supplement contained less than half the amount claimed. Of 23 top-selling vitamin C pills, one provided less than half the amount promised; the suggested dosages of some others were beyond recommended safe levels. Of 10 vitamin A supplements, one provided twice its stated amount, raising concern about toxic side effects.
Ok they above sounds like a rip off: claiming to have something in it that just isn't there. But the problems don't stop there. What about putting crap into the supplement that isn't on the label and may be a banned substance or just some crap drug? This too has apparently happened:Last year, nearly 200 people were sickened by supplements containing up to 200 times the amount of selenium stated on the label. Symptoms included hair loss, discolored and painful fingernails, muscle cramps, joint pain, diarrhea and fatigue.
So what is a consumer to do?Spiking Your Shake"Random batch spiking" has a long history in the supplement business. It works like this: "The manufacturer sprinkles an illegal substance into an over-the-counter dietary supplement," says Feliciano. "The legal ingredients are claimed on the label, but they don't disclose the drug."
Chris Lockwood, formerly the senior category director of diet, energy, food, and beverage at the supplement retailer GNC and now a doctoral candidate in exercise physiology at the University of Oklahoma, recalls taking a popular protein powder in the early 1990s: "When I first took it, I got great gains. I felt great. I got strong. I got lean. But then something happened to it." Years later, he related his experiences to one of the product's formulators who confirmed for him that the powder had been spiked with Clenbuterol, an asthma drug that supercharges your metabolism.
There are in the US alone about 4 various standards groups that certify supplements against the Good Manufacturing Process. These are Consumer Labs, mentioned above, the NSF, NPA and USP (we'll come back to these in a second). According to Wikipedia's entry on cGMP, this means,
Since sampling product will statistically only ensure that the samples themselves (and perhaps the areas adjacent to where the samples were taken) are suitable for use, and end-point testing relies on sampling, GMP takes the holistic approach of regulating the manufacturing and laboratory testing environment itself. An extremely important part of GMP is documentation of every aspect of the process, activities, and operations involved with drug and medical device manufacture. If the documentation showing how the product was made and tested (which enables traceability and, in the event of future problems, recall from the market) is not correct and in order, then the product does not meet the required specification and is considered contaminated (adulterated in the US). Additionally, GMP requires that all manufacturing and testing equipment has been qualified as suitable for use, and that all operational methodologies and procedures (such as manufacturing, cleaning, and analytical testing) utilized in the drug manufacturing process have been validated (according to predetermined specifications), to demonstrate that they can perform their purported function(s).Process Check vs Spot Check. In other words how the stuff is made is checked, not just a given batch "randomly" selected to be tested by a lab. On some bulk supplement sites, they will post batch "certificates of purity" as a kind of quality control - and a person then has to take it on faith that that certificate matches up with the batch actually in the holder's control and that is then being parceled out from that batch (in another process, introducing another opportunity for contamination) into smaller tins.
In contrast, with GMP, the process of how a supplement is made is submitted to the certification body, assessed against the certification group's standards, and then audited in practice. The specific details of each group's auditing process are detailed on their sites, but here are the types of things they consider for certification:
USP (US Pharmacopia)
The USP Verified Mark helps assure consumers of a manufacturer's commitment to quality and helps them easily identify and choose a product thatA list of USP cert'd supplement companies can also be found on their web site.
- contains the ingredients listed on the label, in the declared potency and amount
- does not contain harmful levels of specified contaminants
- will break down and release into the body in a specified amount of time
- and has been made according to the FDA's Good Manufacturing Processes
"Will break down and release into the body" is a pretty important thing, isn't it? Seems obvious, but some supplements in those ConsumerLabs.com random tests have been shown to be inert - they don't break down at all even in acid, never mind water, like ever.
What does NSF certification of a dietary supplement mean to consumers?They seem to be missing that disolvability eh? But you can also check if your brand uses the NSF for their certification. Likewise if you're concerned about banned substances, NSF makes a business of certifying for this compliance, too.
NSF International was one of the first organizations to develop an independent product evaluation program to address the rapidly growing dietary supplements industry.
The purpose of our voluntary program is to test and certify dietary supplements products to
- verify the identify and quantity of dietary ingredients listed on the product label;
- ensure the product does not contain undeclared ingredients or unacceptable levels of contaminants; and
- demonstrate conformance to currently recommended industry Good Manufacturing Practices (GMPs) for dietary supplements.
Why so many certification labs? It's a business. NSF also tests tools. ConsumerLabs tests everything. USP and NPA don't. Why might a company choose one cert over another? Good question. Certifications cost money. One might also believe that the auditing practices of one group seem more amenable than another. It's worth digging into each program to see what you would find most comforting.
Natural Products? For instance, some of us like to privilege "natural" products in our supplements over synthetics. Whether there is a clear difference in terms of absorption or not can be debated, and indeed the vitamin D2 vs D3 debate is a great example of such a discussion (though vitamn D2 is from natural products that are vegetarian sourced and then irradiated rather than from squished fish and animal parts, but i digress).
For that preference, there is a GMP certification group focusing on standards for naturals. Called, naturally enough, the Natural Products Association. Their guidelines for GMP spec are quite detailed, too. They have a considerable list of companies on their listings as well, and it's great that these can be checked.
In the EU, the standards seem to be incredibly weak. Ya have to demonstrate that in quantity and quality, they are safe. Placebo is safe: having nothing in the supplement including what's on the label, is safe. Despite this breadth, the UK fought them: why pay money to say what you've been selling for years is safe, went the argument - at least in part. Gosh, sport, i dunno. Maybe it's NOT. That said, some folks think the legislation is protecting law makers rather than conusmers. But then what IS a consumer to do who wants to make sure what's on the label is what's in the tin?
In the UK, some companies do send their products to be tested. But that's product testing, not product process auditing. When they want to prove their goodness in terms of GMP, they can go the ISO (international standards) route and get ISO 9001:2008 accreditation.
ISO 9001:2008 specifies requirements for a quality management system where an organizationSo far, myprotein.co.uk, claims to be the sole UK supplement maker with the 9001:2000 certification, never mind the ultra recent 2008 version (it takes the better part of a year or more to get to that certified process so no wonder myprotein has just been able to announce the slightly earlier standard).
All requirements of ISO 9001:2008 are generic and are intended to be applicable to all organizations, regardless of type, size and product provided.
- needs to demonstrate its ability to consistently provide product that meets customer and applicable statutory and regulatory requirements, and
- aims to enhance customer satisfaction through the effective application of the system, including processes for continual improvement of the system and the assurance of conformity to customer and applicable statutory and regulatory requirements.
Becuase i say so? Another company that makes natural products in the UK and claims to use Good Manufacturing Practice, for made-in-uk supplements, however, doesn't say how that claim is verified.
Another supplement shop suggests that GMP in the UK is self-regulated: it's GMP compliant if we say it is:
What is GMP?I have not been able to find anything to show either that there is anything other than a shop claiming that their supplements follow GMP protocols in order to claim GMP "certified." That said, it seems like the only real EU-wide objective approach is the ISO 9001:2000/2008 certification. As in the states, there are a variety of groups set up to help organizations meet these criteria and get their practices assessed by accredited labs.
Good Manufacturing Practice (GMP) offers quality assurance; it is a set of strict pharmaceutical regulations, codes, and guidelines that ensure that food supplements are constantly manufactured and controlled to a high standard which is suitable for use. Within the UK it is only legally applicable to medicines and veterinary medicines, however, GMP is a self-regulatory code within the supplements industry which is used alongside the regulations that are set out within the Food Supplements Directive.
Simply Supplements’ purchasing team ensure that all of our supplements comply with the Food Supplements Directive and that countless products are GMP certified.
June 2010: Law comes back to the Supplement Wild West - sort of. Back in the states, apparently by June 2010, supplement companies will have to be compliant with minimum GMP to sell their wares (pdf of whole rule here). Hoorah. Sounds wonderful, doesn't it. Here's the irony. Remember, this law/ruling is for Dietary Supplement makers. So watch this exception:
The most important and obvious change is that the final rule does not apply to dietary ingredient suppliers and manufacturers. The burden of compliance with cGMPs fully lies with the dietary supplement’s manufacturer and requires dietary supplement manufacturers to test 100% of the incoming dietary ingredients.Excuse me? So this sort of means that while manufactures have to be able to say what their processes are and list that their processes follow GMP, and that will take some cost and effort, who's to say what's on paper is what they do? Who is going to police this? The FDA itself is woefully understaffed. And while it can carry out random inspections, is the cost of a fine cheaper than the cost of changing manufacturing practice?
GMP - better than a kick in the head. There's something to be said, perhaps, for companies who have taken it upon themselves to pick up the cost of quality assurance third-party certification. There can be corruption everywhere, to be sure. Inspectors paid off, etc etc, but for the most part, why bother with the certification then? There seem to be a thriving fleet of businesses making money on supplements without any breath of certification.
So, take away: the above may help explain why some products cost a *little* more than others. Certification is not the big cost, but production mechanisms, practices and oversight for compliance DO cost more.
If the result of that process is both a safe-from-contaminent and quality product such that what's on the tin is *in* the tin, then that is value for money.
If you're not sure if your favorite supplement shop is GMP certified by a third-party, why not ask them? If enough people do ask, they might up their game. They may say no, they can't afford to raise prices. Likewise, you may decide it's too great a risk of potentially wasting your money *not* to get your sups from a GMP certified source.
ps - supplements that are likely *worth* investing in, based on the best of what we know?
- fish oil or equivalent broad spec fatty acids
- vitamin d
- a multi
- some e
- some magnesium
whey protein, creatine, b complex - the research on these guys is so long standing now and so repeated in terms of results, it's hard to argue. THough i would say pea protein and rice protein are also great alternatives - as algae oil seems to be for fish oil.
So for the few things that have been shown to add real benefit, may be worth chasing down the ones with the highest certified potency/quality/purity?
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Friday, July 24, 2009
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
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.
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:
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
Thursday, July 23, 2009
Sökmen, Bülent; Armstrong, Lawrence E; Kraemer, William J; Casa, Douglas J; Dias, Joao C; Judelson, Daniel A; Maresh, Carl M
Cool. What the study suggests is that well hmm, all the use of taurine or (my fave) tyrosine to boost hard workouts etc may be set aside for a low dose snort for a few days leading up to that "intense training."
AbstractThe ergogenic effects of caffeine on athletic performance have been shown in many studies, and its broad range of metabolic, hormonal, and physiologic effects has been recorded, as this review of the literature shows. However, few caffeine studies have been published to include cognitive and physiologic considerations for the athlete. The following practical recommendations consider the global effects of caffeine on the body: Lower doses can be as effective as higher doses during exercise performance without any negative coincidence; after a period of cessation, restarting caffeine intake at a low amount before performance can provide the same ergogenic effects as acute intake; caffeine can be taken gradually at low doses to avoid tolerance during the course of 3 or 4 days, just before intense training to sustain exercise intensity; and caffeine can improve cognitive aspects of performance, such as concentration, when an athlete has not slept well. Athletes and coaches also must consider how a person's body size, age, gender, previous use, level of tolerance, and the dose itself all influence the ergogenic effects of caffeine on sports performance.
Now the big contribution of this article for practical applications in coaching is that it looks at a bunch of effects that need to be considered to build an appropriate "dosing strategy"
Power/Speed Very Fast. The article begins its consideration by looking at caffeine's effects on power. Main hit: peak power in 6 secs of the wingate test. So benefit to phosphagen system dominant activities. Caffeien also seems to lower pain perception. hmm. IF you've ever done a wingate test that could be a Good Thing. Not so clear (yet) there's any big boost to glycolytic-heavy events.
Cognitive Function and Skill. Intriguingly in sports like Tennis, the paper shows, hitting accuracy has gone up. Now is that because of its mental altertness effects? or the CA++ happening? The authors really emphasize that caffeine use has to be thought of not as a single factor effect, but look at the range of ways it acts on physiologic as well as cognitive function. And habituation. A biggie on figuring out dosing is how habituated to it a person already is.
Withdrawl. Likewise, the inverse of being on caffeine is going off it. So if there's a desire to increase the effectiveness by getting off it for awhile before a competition, then the authors recommend being sure to do so at least a week before, since reactions to withdrawl are individual but generally peak 24-48 hours after stopping. From personal experience, these can be harsh. The authors actually suggest tapering off rather than cold turkey to reduce training impact.
The key thing in the study is not being a big caffeine head already so that one is not tolerant of it.
Dosing. And what do we mean by caffeine head? Apparently not necessarily a coffee drinker. Coffee it seems can actually blunt the effects of caffeine, so for performance, we're talking capsules.
THen the question is how much and when? low level doses during the day (75mg) improved cognitive function over the day. Costs? sleep gets screwed up, which has its own negative effects on other aspects of performance. SO how use the fact that caffeine effects peak about 75mins post ingestion and are cleared from the body in about 6-7 hours post ingestion?
Again, super cool that a dose as small as 5mg (that's it; just 5mg) can have a huge effect on someone not habituated to caffeine. And that in men, 10mg (and that's it) significantly reduced the experience of leg pain in a cycling experiment. What about the habituated? The authors say that recent work has shown that there's no bigger ergogenic effect in taking anything greater than 9 mg·kg.
SO considering that the usually size of a caffeine pill is 200mg, are we perhaps overdosing?? The authors might say "that depends." What's your dosing strategy??
HYDRATION AND CAFFEINE. And did you know, the authors point out, that it's a big misconception that caffeine leads to dehydration. As to the popular use of blending caffeine with everything else? dunno - yet "The effects of ingesting caffeine with a carbohydrate solution, with an amino acid solution, and during creatine loading require further study."
Bottom line: caffeine use can be great for certain types of sports performance stuff; low dosing with as little as 5-10 mg (that's nothing - but it's super something) can be hugely significant.Key thing: figuring out a dosing strategy is "multi-factorial" - it's not well i gotta run all day tomorrow so i'll amp up caffeine in the morning with my double espresso." Dam.
DOSING STRATEGY: small. The above is a great example of what makes a survey article super: it's able to look at a wealth of data on a topic over years and see where the consensus lies, if there's consensus. Here, it's pretty clearly, happily, less is more, and can be a whole lot of more, when dosed smart.
Sökmen B, Armstrong LE, Kraemer WJ, Casa DJ, Dias JC, Judelson DA, & Maresh CM (2008). Caffeine use in sports: considerations for the athlete. Journal of strength and conditioning research / National Strength & Conditioning Association, 22 (3), 978-86 PMID: 18438212Tweet Follow @begin2dig