Monday, July 27, 2009
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