Monday, February 23, 2009

Cutting-Edge Research: Compression Shorts and Muscular Performance

Some manufacturers of compression shorts claim that their garments improve muscle circulation, enhance performance and reduce post-exercise muscle soreness. Indeed, many athletes feel that compression shorts are a necessity. Are these claims true? What does research say about the use of compression shorts? A recent study to be published in the Journal of Science and Medicine in Sport suggests that the effects of compression shorts on performance and recovery from exercise are minimal. However, a review of several research studies does hint at some potential benefit.

The study, conducted at Charles Stuart University in Australia, focused on sprint and plyometric performance and exercise recovery. A group of trained athletes performed a series of 10 repeated sprints and a series of 10 repeated bounds while wearing typical gym shorts and compression shorts. During these trials, there was no difference in sprint times or bounding distances between the two conditions. This despite that fatigue was apparent in both types of exercise. In the days following the exercise tests, the investigators found no differences in biomarkers of muscle soreness. Nor did they find any differences in electrically stimulated or involuntary muscle force (this is important as it diminishes any potential of a placebo effect – see below). These results lead the investigators to conclude that the use of compression garments probably does little to reduce fatigue or enhance the recovery of performance in the days following exercise.

A review of the scientific studies on the effects of compression garments on muscle performance shows that research results are very inconsistent. Most of the studies fail to find any improvement in speed or power but a few studies show small improvements. The studies which demonstrate positive effects on performance typically report very small improvements which may be due to factors other than the shorts. No study has shown any adverse effect. Based on the results of 4-5 well conducted studies studies, it is questionable as to whether or not compression shorts enhance performance.

These research studies do lead to two fairly firm conclusions. First, there seems to be a rather strong placebo effect of wearing the shorts. Nearly all of the studies report that the athletes felt they performed better and experienced less muscle soreness after wearing the shorts. Thus, the athletes perceive that compression shorts are beneficial. Unfortunately the unbiased physiological measurements do not support the athletes’ perceptions.

Second, the shorts do seem to reduce hip flexion during running and jumping and increase skin temperature. This raises the possibility that compression shorts might provide some protection against hamstring injuries. The emphasis here is “possibility” and “might”. None of the studies provided any data to support a firm claim of injury protection and more research is needed to address this question. Nevertheless, there is the possibility that compression shorts might aid in reducing the risk of hamstring injuries.

Based on the published research, it is clear that compression shorts do not hinder exercise performance and may offer some protection against hamstring injuries (although this protection may be minimal). However, they are not likely to offer any improvement in performance nor are the likely to reduce the development of muscle soreness (although athletes may perceive benefits). Therefore, there is no reason to discourage athletes from wearing compression shorts during training or matches but they should not expect to receive any measurable benefit on performance.

Reference:

Duffield R, Cannon J, King M (2009) the effects of compression garments on recovery of muscle performance following high-intensity spring and plyometric exercise. J Sci Med Sport, doi: 10:1016/j.jsams.2008.10.006.