Last week I introduced you to this series reviewing the research on compression garments as a recovery modality, particularly in team sports. Now we are aware of the considerations across a variety of factors with the garments, we will take a look at the evidence in relation to one of the main claims for using compression garments; reducing muscle damage and inflammation.
Muscle Damage and Inflammation
Kraemer et al (2001) was the first to report a blunting of muscle damage with compression garments after an acute soft tissue muscle injury. More recent research has added to this work with the collection of blood biomarkers to assess the efficacy of compression garments. Given the associations between Creatine Kinase (CK) and intense muscle trauma, CK has been used as a measure of recovery and consequently to assess the effectiveness of recovery strategies. Following muscle damage various cytokines, such as Interleukin 6 (IL-6) and Interleukin 10 (IL-10) are released to initiate and moderate the inflammatory response.
In a recent study by Bieuzen and colleagues (2014), no benefits were observed with wearing compression garments on indirect markers of muscle damage or inflammation in highly trained off-road runners during trail races. However, given the specific physical demands of off-road running and that the level of Exercise-Induced Muscle Damage (EIMD) was only categorised as ‘mild’ (CK less than 1000 IU/L), these findings may not be replicated in team sport athletes.
One team sport widely reported to elicit large muscle damage is rugby, due in part to the high levels of body contact collisions between opposing players. In a study (Gill et al, 2006) analysing the effectiveness of recovery strategies in elite male rugby players, the magnitude of recovery measured via enhanced CK clearance seen at 36h and 84h post match was greater with lower body compression garments compared to passive recovery. Furthermore, much greater CK levels post competition (2194 IU/L) were found than reported in Bieuzen et al’s (2014) study with trail runners. In fact, the pre competition levels in rugby players were found to have greater CK levels (1023 IU/L) than post exercise in the off road runners (less than 1000 IU/L), which may indicate the players studied were not fully recovered from previous training and matches prior to the start of the study. This highlights the need to consider the specificity of physical demands, muscle damage and training/competition demands across different sports. In another study with professional rugby players, lower CK levels were observed 36 hours post match using a combination treatment of lower body compression garment and electrical stimulation than with compression alone although no control/non-compression trial was used in this study (Beaven et al, 2013) – is electrical stimulation a new frontier for enhancing the effect of compression?
Considering non-collision team sports, a study using highly trained hockey players after a match simulation exercise found no differences in CK or inflammatory mediators (IL1-?, IL-6, TNF-? and CRP) concentrations when comparing compression garments to the control trial at 1h, 24h or 48h post (Pruscino et al, 2013). In addition, despite large (up to approx. four-fold) increases in plasma concentration of muscle damage markers and inflammatory cytokines during tournament basketball, the use of full-length lower limb compression garments had little benefit in clearing these biomarkers at 6h after a game, between games during the tournament or at the end of the three day competition (Montgomery et al, 2008). There were differences witnessed in values for the cytokine IL-6 between these two studies with only a 1.5-fold above baseline values at 1h post match simulation protocol, Loughborough Intermittent Shuttle Test (LIST), (Pruscino et al, 2013) compared to the 3-4 fold increase immediately post basketball (Montgomery et al, 2008). This may have been due in part to the less intense exercise protocol carried out by the hockey players, because as highly trained subjects they were well adapted to the demands of the LIST protocol as demonstrated by their HR, RPE and blood lactate responses. On the other hand, the baseline IL-6 levels were higher in Prusino et al’s (2013) study possibly due to the pre-exercise snack used to control for baseline glycogen stores, which may have influenced the change observed post-exercise.
To try to account for the inconsistent findings and variation in methodologies across the literature, Hill et al (2014) carried out a meta-analysis on compression garment research. They found wearing compression garments reduced concentrations of CK, with analysis suggesting 66% of the population would experience this reduction. However, caution should be urged when interpreting these results because their findings were inconclusive with some studies demonstrating no change and one study with an inexplicably large response at 72h (Kraemer et al, 2001).
There are limitations to inferring muscle damage and/or inflammatory response via blood biomarkers as reported in these studies. The limited timing points of blood sampling used in these methodologies may fail to capture the true cytokine response (Pruscino et al, 2013). There is danger interpreting serum CK as both diffusion and clearance from the circulatory system are occurring (Hill et al, 2014). It should also be noted that there is some debate amongst the literature as to whether post-exercise cytokine response is actually related to the inflammatory response or if cytokines may be more closely associated with adaptation of human skeletal muscle (Malm et al, 2004). Furthermore, although the biomarkers discussed here are widely used to represent Exercise-Induced Muscle Damage (EIMD) their accuracy in representing the magnitude is limited by high intra-individual and inter-individual variability (Bieuzen et al, 2014) therefore we must take this into account when reviewing these findings. This may mean compression garments are more effective for certain individuals and therefore justify the use of compression garments in the applied setting according to individual responses.
In Part 3 of this series I will review the effects on muscle function and physical performance with compression garments.
Jo Clubb
References
Beaven CM, Cook C, Gray D, et al. (2013) Electrostimulation’s enhancement of recovery during a rugby preseason. Int J Sports Physiol Perform 8: 92-98.
Bieuzen F, Brisswater J, Easthope C, et al. (2014) Effect of wearing compression stockings on recovery after mild exercise-induced muscle damage. Int J Sports Physiol Perform 9: 256-264.
Gill ND,Beaven CM and Cook C. (2006) Effectiveness of post-match recovery strategies in rugby players. Br J Sports Med 40: 260-263.
Hill J, Howatson G, van Someren K, et al. (2014) Compression garments and recovery from exercise-induced muscle damage: a meta-analysis. Br J Sports Med 48: 1340-1346.
Kraemer WJ, Bush JA, Wickham RB, et al. (2001) Influence of compression therapy on symptoms following soft tissue injury from maximal eccentric exercise. J Orthop Sports Phys Ther 31: 282-290.
Malm C, Sjoberg B, Lenkei R, et al. (2004) Leukocytes, cytokines, growth factors and hormones in human skeletal muscle and blood after uphill or downhill running. J Physiol 556: 988-1000.
Montgomery PG, Pyne DB, Cox AJ, et al. (2008) Muscle damage, inflammation, and recovery interventions during a 3-day basketball tournament. Eur J Sports Sci 8: 241-250.
Pruscino CL, Halson SL and Hargreaves M. (2013) Effects of compression garments on recovery following intermittent exercise. Eur J Appl Physiol 113: 1585-1596.