Compression Garments have been used medically for many years in the treatment of Deep Vein Thromboses (DVT’s) and other venous problems. The graduated compression has been shown to reduce venous pooling and discomfort and has a positive effect on oedema (Ali, Caine et al. 2007).
Over recent years the sports community have used this concept in the hope that these effects will improve performance. Currently many major manufacturers of sporting clothing have compression garments as part of their clothing ranges. Claims made by these manufactures include: Increased blood flow, increased delivery of oxygen to the muscles, accelerated recovery, and ionisation effects (Canterbury – http://www.compressiontights.com.au/). Skins™ claim research has demonstrated: Reduction in post-exercise muscle soreness, faster removal of lactic acid, increases strength and power and endurance, improvement in body temperature control, and a reduction of in-flight ankle oedema (http://www.skins.net/nz/en/Research/default.aspx).
A search of the recent sporting literature demonstrates the presence of a multitude of studies assessing the effects of compression garments in the sporting population. However, many of these studies report contrary findings, some of which are due to different research conditions and methodologies (all references). One of the key differences in these studies is the garment used. They include a compression sleeve (CS) (Kraemer, Bush et al. 2001), hypercompressive shorts (HC) (Doan, Kwon et al. 2003), and graduated compression garments (GCG) (Ali, Caine et al. 2007; Duffield, Portus et al. 2007; Duffield, Edge et al. 2008) amongst others. Full length sports compression garments tend to be of the GCG type.
Strenuous exercise, especially eccentric exercise, results in muscle damage. Clinically this manifests in symptoms including impaired muscle function, a decreased range of motion (ROM), swelling and a decreased ability to generate muscle tension (Kraemer, Bush et al. 2001). All these symptoms are detrimental to athletic performance. Reduction or prevention of these symptoms may allow improved performance though the ability to continue training. Kraemar et al. (Kraemer, Bush et al. 2001), in a study regularly referenced, assessed the effect of a compression sleeve (CS) on muscle damage and function, and perceived soreness following an exercise protocol which included eccentric loading. The subjects were a group of 20 non-trained females. Following the exercise protocol both the CG and control group experienced muscle soreness, weakness, and other symptoms of muscle damage. However by day 2 post exercise the CG group began to show a lesser reduction of strength and power, reduced muscle soreness and better daily function. Of note delayed onset muscle soreness (DOMS) is said to peak at 48 – 72 hours, the time the improvements were shown.
The above findings have poor relevance to the sporting population where repeated training over many years is unlikely to cause a first time exercise DOMS. However, high intensity exercise with a large stretch shortening cycle component, such as plyometric training, may cause similar muscle damage in an athletic population. A sprinting / bounding protocol was used in moderately trained athletes to assess if compression garments (GCG) aided recovery in 11 sportsmen (Duffield, Cannon et al.). Physical and physiological markers suggested that the protocol used created muscle damage in the participants. Though there was a small improvement in perceived muscle soreness and one measure of muscle damage in the GCG group 24 hours post exercise there was no other significant changes between the two groups, and muscle performance had recovered to insignificant differences after two hours. Though non significant, the authors did note a moderate effect size in bounding fatigue with the compression garment group not decreasing in distance as much as the control group. The significance in this effect size would be determined by the athlete’s sport as to whether this would provide a “winning” advantage.
Performance measures have been assessed in track athletes wearing compression shorts (HC) (Doan, Kwon et al. 2003). These shorts are not traditional sports compression garments, and are 15% smaller than normal fitting garments. Performance measures included sprint time and kinematics, jump power, and muscle oscillation. Results demonstrated no changes in sprint times, however, there was a significant reduction in hip range of motion. Jump height, as a measure of power, and muscle oscillation significantly improved. It was suggested that the elastic properties of the garment were largely responsible for these changes by improving torque generated at the hip. The reduced muscle oscillation may reduce muscle damage during exercise.
Compression garments are used in many ways, with some athletes using them after exercise as a recovery tool while others using them during and after exercise. Is there evidence of a benefit of one way over any other? Two performances on the same day were assessed by Ali (Ali, Caine et al. 2007) to see if knee length compression garments (GCG) made a difference to performance and recovery. A small group of trained athletes, in a cross over design, performed two beep tests with a one hour recovery. The study group wore the garments though out the procedures and until they were then followed up, 24 hours after the last run. There were no significant changes in exercise performance, heart rate or perceived muscle soreness.
The same research group then looked at a 10km set pace run repeated 3 days apart (Ali, Caine et al. 2007). In this study there were significant changes with perceived soreness higher in the control group at 24 hours after activity. Though not significant they also noted that 10/14 ran faster in the garment group, as well as having and overall lower heart rate. Similarly a group of U21 rugby players undertook 2 simulated game activities on consecutive days (Duffield, Edge et al. 2008), with the experimental group wearing garments (GCG) during and after activity. Of a multitude of tests including blood lactate, muscle damage, heart rate, and sprint and power measures, only perceived muscle soreness was significantly different between groups with it being higher in the control group over 48 hours post exercise.
One of the other claims the manufactures make regarding compression clothing is an improvement in temperature control2.It has been shown else where that elevated core temperature promotes fatigue (Houghton, Dawson et al. 2009). Using a modified beep shuttle test to simulate game conditions, Houghton et al. (Houghton, Dawson et al. 2009) assessed the effect of a shirt and short compression garment (graduation not specified) on internal and skin temperature, as well as physiological measures. Testing was conducted in a cool environment as the authors claimed the garments were more likely to be used in a cooler than warmer environment for its thermal properties. Results showed that core temperature was higher before testing, but there was no change during the testing procedures. Skin temperature, however, was higher in the compression garment than the control. Blood lactate, heart rate, perceived exhaustion, and sprint speed were not affected. The authors suggested the rise in the skin temperature may have been due to the inability of the sweat to evaporate. It therefore can be concluded from this study that in this environment that the compression garments provided no benefit, but also was not detrimental, to performance. The temperature control claims need further evaluation.
If these garments are designed for athletic performance and recovery the question needs to be asked – does a change need to be significant? In the above studies perceived muscle soreness is commonly demonstrated to be significantly improved in the compression garment group but as Duffield’s study (Duffield, Cannon et al.) notes there may be effect size changes. Scanlan (Scanlan, Dascombe et al. 2008) also talks about “practically significant” changes. Using a one hour cycling time trial they noted a ‘likely practically significant’ increase in power output at anaerobic threshold and a ‘possible practically significant’ improvement in muscle oxygen economy. No other measures including VO2 max and many physiological measures showed change. These above mentioned types of changes may make a difference over a time trial, but may not help a forward in rugby.
Finally are all the garments the same, as if not then this may explain some of the variable findings in the literature. Already it has been noted that recent research has used at least 3 styles of garment (CG, GCG, HC) as well as different lengths of garment with longs, shorts, and short and long sleeve tops. Three common full length compression garments (GCG) were compared in a study on throwing and sprinting in cricketers (Duffield, Portus et al. 2007). In this study garments were worn though out the testing. Results demonstrated a significantly lower creatine kinase (CK) and muscle soreness post exercise compared to controls but no difference between garments. Mean skin temperature was also higher in the garment group but not different between groups.
In conclusion compression garments have become a popular sporting accessory in recent years despite inconclusive research about its effects. However, the recent research uses many sporting models and as many garment types which may account for these results. Key consistent findings include a reduction in post exercise perceived muscle soreness when garments are worn during, and after, exercise. This may provide a psychological benefit to the athlete, but could also be due to physiological changes not measured / measurable. However, studies noting high levels of muscle damage as shown by CK levels, or other physiological measures, have shown better recovery. Surface body temperature also appears to be higher, though this has not been shown to be either detrimental or beneficial to performance, but may be of value in colder environments. Finally muscle oscillation is reduced, most likely due to the compressive support. It is speculated that this may help performance and reduce muscle damage.
In deciding to recommend compressive garments to an athlete consideration should be given firstly to any detrimental effects. In the reviewed recent literature there appear none. Next consideration should be given to when and how they are used, which may depend on the sport or activity. This may be determined by whether a significant change, or performance effect, is needed to change an outcome. It may also be whether there will be noticeable muscle damage involved.
Canterbury Compression Clothing. http://www.compressiontights.com.au/ Downloaded 20.11.09
Skins Compression Clothing. http://www.skins.net/nz/en/Research/default.aspx Downloaded 20.11.09
Ali, A., M. P. Caine, et al. (2007). “Graduated compression stockings: Physiological and perceptual responses during and after exercise.” Journal of Sports Sciences 25(4): 413-419.
Doan, B. K., Y. H. Kwon, et al. (2003). “Evaluation of a lower-body compression garment. .” Journal of Sports Sciences 21(8): 601-610.
Duffield, R., J. Cannon, et al. “The effects of compression garments on recovery of muscle performance following high-intensity sprint and plyometric exercise.” Journal of Science and Medicine in Sport In Press, Corrected Proof.
Duffield, R., J. Edge, et al. (2008). “The Effects of Compression Garments on Intermittent Exercise Performance and Recovery on Consecutive Days.” International Journal of Sports Physiology & Performance 3(4): 454-468.
Duffield, R., M. Portus, et al. (2007). “Comparison of three types of full-body compression garments on throwing and repeat-sprint performance in cricket players ” Br J Sports Med 41(7): 409-414.
Houghton, L. A., B. Dawson, et al. (2009). “Effects of wearing compression garments on thermoregulation during simulated team sport activity in temperate environmental conditions.” Journal of Science and Medicine in Sport 12(2): 303-309.
Kraemer, W. J., J. A. Bush, et al. (2001). “Influence of compression therapy on symptoms following soft tissue injury from maximal eccentric exercise.” Journal of Orthopaedic & Sports Physical Therapy 31(6): 282-290.
Scanlan, A. T., B. J. Dascombe, et al. (2008). “The Effects of Wearing Lower-Body Compression Garments During Endurance Cycling.” International Journal of Sports Physiology & Performance 3(4): 424-438.