Dear VeloNews Training Center,
I’ve seen many pro athletes wearing compression socks and other compression recovery clothing on their arms and legs. Is there any scientific data to support the claims made by these manufacturers? I’ve read a few websites that say yes, others that say no. Can you clarify what these do for you and whether the science supports the marketing?
Good question, Chuck! The popularity of compression garments has increased significantly recently and with that has come more interest in studying their possible benefits.
Reviewing the studies that have been published in regards to compression gear is challenging as there is a great deal of variability in what sport-specific activities were used to assess performance and in regards to the wide differences in lengths and intensities used. Other caveats are what compression gear was used to test subjects (i.e. full compression tights, below the knee socks, pressure amount and graded vs. non-graded pressure garments), differences in length of time worn after event, the limited numbers of subjects tested and the inherent difficulty in blinding the subjects to compression vs. controls.
Compression socks in individuals with histories of venous insufficiency have been documented in well-designed studies to decrease the risk of deep vein thrombosis and to mitigate lower extremity edema. The reported benefits to the exercise community purveyed by compression gear marketers include increased mechanical support for working muscles, faster removal of cellular debris after exercise induced muscle damage, and improved physiologic exercise parameters secondary to alterations in hemodynamics.
Taking a closer look at published research regarding performance, Kemmler et al. in Germany found improved running performance in 21 moderately trained runners on a graded treadmill test while wearing below the knee compression socks. Interestingly there was no significant change in runner’s VO2 max values, but there appeared to be improved economy at varying metabolic thresholds.
Scanlan et al. in Queensland, Australia looked at performance parameters in 12 well-trained cyclists in full-length lower leg compression garments vs. controls by doing two randomly assigned stepwise incremental tests and two randomly ordered one-hour time trials. They concluded that there were limited physiological benefits from compression vs. control and no performance enhancement despite a possible trend towards significance in improved power at anaerobic threshold and muscle oxygen economy.
Sperlich et al. in Germany on the other hand found no performance benefits in well-trained endurance athletes performing submaximal (70% VO2max) and maximal tests on a treadmill using control socks, below-the-knee compression socks, compression tights and full body compression suits in regard to oxygen uptake, lactate concentrations, perceived exertion ratings, muscles soreness and time to exhaustion values.
Using recovery as a gauge in the evaluation of compression gear, researchers from South Africa studied 62 endurance runners who wore below-the-knee compression socks either during a 56km road race or for 72 hours after the event. They found decreases in creatine kinase levels (a skeletal muscle injury marker) of 37% and 48% at 24- and 48 hour respectively after the event in the athletes that wore compression socks during the race vs. those that donned the socks for the 72 hours afterwards.
Similarly Ali et al. in Auckland New Zealand found improved ratings of perceived whole body soreness amongst 14 well-trained athletes completing fast-paced outdoor 10km road running trials when wearing below-the-knee compression socks vs. controls.
After reviewing these studies there appears to be no improvement in Vo2max values in athletes wearing compression gear, but perhaps a trend exists in improved exercise economy. In regards to eccentric exercise, in particular running, wearing compression socks during the event likely does help decrease skeletal muscle damage and/or improve delayed onset of muscle soreness. It is hard to say if this translates to cycling-specific activities as there are big differences in the eccentric demands on the calves in running vs. biking.
My advice is that they are a relative inexpensive item and encourage athletes to try them out and see what they think. They can’t be beat for long plane trips to avoid the post flight leg bloat and although good data regarding compression gear is still lacking and equivocal in some respects, there are no negative outcomes in the existing studies.
—Jason Glowney, MD CAQSM
Boulder Center for Sports Medicine