By Dr. Jeffrey A Chan, DC, CSCS, ART
In the past several years you have probably seen a few people on the trails or at a race wearing compression socks. In the elite world of track and field, they are not quite as common but a handful of athletes swear by them. If you ask why they wear them you will hear a different answer from each one of them. Some of the benefits I have heard from frequent users are reduction in muscle soreness, alleviation of muscle cramps, the additional support and simply the warmth the extra layer provides. What I don’t often hear is how the individual thinks the sock actually works.
Compression socks have been used for quite some time for medical purposes treating conditions that involve chronic dysfunction of the circulatory system. In certain diseases, the body has difficulty resisting gravity in returning blood back to the heart. When this occurs blood can pool in the lower extremity especially around the ankles. Edema, deep vein thrombosis, phlebitis and pregnancy are examples of such venous insufficiencies.
You may have also heard of the use of compression socks for air travel on longer flights. Isayev et al. describe how during air travel blood can thicken and form a clot that can travel to the lungs forming a pulmonary embolism and ultimately causing a stroke. Contributing factors include dehydration (which causes the blood to thicken), immobility, and previous history of having a stroke, embolism or thrombosis. The recommendation of compression socks is used to help counter this state by using its elasticity to exert pressure on the veins and decreasing its diameter to increase blood flow. It is essentially the same as putting your thumb at the end of a hose to accelerate and add water pressure. In terms of athletic performance, this is the same system that companies are trying to target.
Meb Keflezighi wearing white compression socks.
- Photo by Jeffrey A Chan
One of the manufacturers, C.E.P., claim that the constant compression allows the arterial walls to relax which “increases oxygen rich blood flow by up to 40%” and thus increasing performance by up to 5%. For recovery, they state that recovery time is shortened and blood flow is increased up to 30%. Their company website has one study for each of these two statements that you cannot find because they do not properly cite them. C.E.P. also has a bulleted list of various conditions that it has “Proven” to reduce which includes shin splints and “Achilles Issues”. The Zensah company has “improved athletic performance” on a bulleted list in its product description without any further explanation beyond that on their webpage. 2XU cited three studies done by the Australian Institute of Sport on their website without providing citation or explaining the methodology of their research. They also state “improved race times” next to the product description of one of their socks.
Looking into more objective literature the quantity is sparse in describing the physiology and utility of compression socks while running. Sperlich et al. performed a review of 37 studies and found no benefit from any type of compression clothing for competitive sports from a scientific standpoint. Kemmler et al. found improvement using VO2 max as a measurement but attributes some of this improvement to indirect factors. They state that, “Increased compression and biomechanical support of the muscle tissue and muscle tendon unit may lead to a higher mechanical efficiency, resulting in less metabolic costs at given workloads.”
Ali et al. found no difference with race times using compression socks over the course of a 10k race though they did find significance in reduced muscle soreness. The facilitation of blood flow to tissue enhances recovery by bringing more nutrients for repair to the area (This is why you do a cool-down jog after a hard workout). Bringard et al. found “increased calf muscle oxygenation” as well as “wearing compression tights decreased the energy cost of running at some submaximal intensities compared with conventional shorts...”
As you can see there are many physiological factors that need to be controlled before we can make more substantial conclusions. It’s premature to make a statement for a product that has conflicting results in a laboratory setting especially when using the word, “proven”. Compression socks are still in their early stage of implementation. If you decide to purchase a pair, and you may need several, I would recommend going in with the mindset that it will help you more so with recovery as opposed to performance as that is as close of a consensus as the literature shows. It would be best to use the socks with no expectations and figure out for yourself where it stands with how you feel. Remember, athletes of all types and abilities have their quirks and superstitions that don’t have clear reasoning or explanation. This could be yours.
Dr. Jeffrey A Chan, DC, CSCS, ART
A. Ali, M. P. Caine, & B. G. Snow. Graduated compression stockings: Physiological and perceptual responses during and after exercise. Journal of Sports Sciences, February 15th 2007; 25(4): 413 – 419
Berry, M. J., & McMurray, R. G. (1987). Effects of graduated compression stockings on blood lactate following an exhaustive bout of exercise. American Journal of Physiology and Medical Rehabilitation. Volume 66: 121 – 132.
Bringard, A.; Perrey, S.; Belluye, N. Aerobic Energy Cost and Sensation Responses During Submaximal Running Exercise – Positive Effects ofWearing Compression Tights. Int J Sports Med 2006; 27: 373–378
Conley DL, Krahenbuhl GS. Running economy and distance running performance of highly trained athletes. Med Sci Sports Med 1980; 12: 357–360
Doan BK, Kwon YH, Newton RU, Shim J, Poppe EM, Rogers RA, Bolt LR, Robertson M, Kraemer WJ. Evaluation of a lower-body compression garment. J Sports Sci 2003; 21: 601–608
Isayev Y, Chan RK, Pullicino PM. "Economy class" stroke syndrome? Neurology. 2002 Mar 26; 58(6):960-1
Kemmler W, von Stengel S, Köckritz C, Mayhew J, Wassermann A, Zapf J. Effect of compression stockings on running performance in men runners. J Strength Cond Res. 2009 Jan;23(1):101-5.
Kuster MS, Grob K, Kuster M, Wood GA, Gachter A. The benefits of wearing a compression sleeve after ACL reconstruction. Med Sci Sports Exerc 1999; 32: 368–371
Rimaud, D, Calmels, P, Roche, F, Mongold, JJ, Trudeau, F, and Devillard, X. Effects of graduated compression stockings on cardiovascular and metabolic responses to exercise and exercise recovery in persons with spinal cord injury. Archives of Physical Medicine and Rehabilitation 88: 703–709, 2007.
Sperlich B, Born DP, Haegele M, Zinner C, Holmberg HC. Effects of compression textiles on performance enhancement and recovery. Sportverletz Sportschaden. 2011 Dec;25(4):227-34.