On Facts and Fads
115
A recent column (2015) by NY Times science writer Gretchen Reynolds examined a new study and other recent research on a training aid that has become very popular among runners over the past few years: compression garments.
As Reynolds explains, the purported benefits of compression socks, leggings, shirts, etc., include:
- Improved exercise performance
- Improved balance
- accelerated recovery time
- reduced fatigue and post-exercise soreness
The thinking behind these claims seems intuitive enough; the supposition being that the elastic, compressive material acts as a massaging-agent, helping to boost circulation to the muscles, which would affect all of the above parameters.
You can read the full column yourself if you are interested in the details, but I will briefly summarize it for you here by reporting that the research indicates that any benefits obtained from wearing these garments appears to be purely perceptual; i.e., due to the placebo effect. Controlled studies that looked at purely objective, measurable physical effects showed no significant improvements.
Seeing this, as well as a current TV commercial showing NFL quarterback Peyton Manning sitting in a whirlpool tub filled with ice water (Losing feeling in my toes) reminded me of another research article I came across recently on the subject of post-exercise cold water immersion (CWI).
As I noted several years ago in an earlier column (Article #87), the practice of using so-called ice baths immediately after prolonged or strenuous exercise for the purpose of reducing delayed-onset muscle soreness (DOMS) and promoting recovery is one that has been around for many years, and not without a fair amount of research to support it. Many studies in the past have found that CWI does have such benefits, at least as measured by subjective reports.
A current study (2), however, raises a good point in noting that no previous investigation looked at the placebo effect as a factor in leading to these positive outcomes. This study’s research design, therefore, attempted to evaluate this potential factor.
The study compared three groups of 10 individuals after high-intensity training (HIT). One group sat in a tub of water at a temperature of approximately 50°F. A second (control) group was in a tub set to 94°F. The third group and the one that differed from previous studies was also in 94°F water, but they were told that the water contained a special solution of recovery oil that was as effective as cold water in promoting recovery. This group, then, was classified as the placebo group.
Various physical and subjective outcomes (intramuscular temperature, quadriceps muscle strength recovery, pain, psychological measures of readiness for repeated exercise) were compared after the exercise and immersion sessions. Muscle temperature in the CWI group clearly decreased an average of 10% compared to the control and placebo groups; that physical change alone would lead us to expect that there would be similar differences found when looking at the other outcomes.
The actual findings, though, did not follow this script. Overall, the cold water immersion group scored better than the control group on those measures, as we would expect, but in fact there was no significant difference between the cold water group and the placebo group with respect to the other measures! It seems that simply setting up an expectation that warm water infused with a special solution was as effective as cold water in improving recovery time, strength, and pain levels, despite there being no change in muscle temperature, which is the theoretical reasoning behind taking an ice bath. This evidence indicates there may be no actual physical change causing these improvements.
Compression clothing and ice baths are just two of the many measures I have seen runners use over the past 40 years to try to gain an edge in athletic performance, muscle soreness, and recovery time. The question can legitimately be asked, are these simply fads or are they supported by scientific evidence? In these two examples, it would appear the answer is the former, but if so, is it necessary to advise people to avoid them?
The answer to that rests on the question of whether or not there is any harm in using them. If done properly, there probably is no harm in taking an ice bath (George Costanza’s concerns notwithstanding), and the singular downside to compression clothing appears to solely be the cost. Based on that, it really is an individual decision if you feel better, who cares what the reason for it really is?
(1) http://well.blogs.nytimes.com/2015/01/14/can-compression-clothing-enhance-your-workout/?_r=0 [New York Times, January 14, 2015]
(2) Med. Sci. Sports Exerc., Vol. 46, No. 11, pp. 2139-2147, 2014