Effects of Wearing Compression Stockings
This systematic review investigated the effects of wearing below-knee compression stockings (CS) on exercise performance (or sports activity) and associated physiological and perceived indicators. We searched articles on PubMed using the following terms: “graduated compression stockings”; “compression stockings”; “graduated compression socks”; “compression socks” combined with “performance”, “athletes”, “exercise”, “exercise performance”, “fatigue”, “sports” and “recovery”, resulting in 1067 papers. After checking for inclusion criteria (e.g., original studies, healthy subjects, performance analysis), 21 studies were selected and analyzed. We conclude that wearing CS during exercise improved performance in a small number of studies. However, wearing CS could benefit muscle function indicators and perceived muscle soreness during the recovery period. Future research should investigate the chronic effect of CS on Sports Medicine and athletic performance.
The prevention of deep venous thrombosis is one of the first evidence-based benefits of wearing compression sleeve, demonstrated by a clinical experiment in which CS improved the venous return by increasing femoral vein blood flow velocity in hospitalized patients.1 Over time, the interest from the basic medical area has expanded to other fields like Sports Medicine.2 Nowadays, recreational and professional athletes have used CS as a tool for improving performance or accelerate recovery from training or competitions, and also to reduce lower limb volume,3,4 relieve symptoms of muscle soreness, and fatigue.3–6 Such popularity is probably boosted by the possibility to obtain potential ergogenic benefits with a simple and low-cost aid.
There are different types (e.g., shorts for thighs, full-leg) and application modes (e.g., using only after the exercise) for compression garments. However, using CS (bellow-knee) “only during” the exercise are probably more practical (than during recovery, after-exercise) for a significant number of sports/activities. For example, uniform issues would limit whole-body garments in some sports. Also, athletes living in tropical locations could be unmotivated to wear compression garments after training sessions once those garments usually promote higher skin temperatures.7,8 Additionally, there is limited evidence regarding the effects of wearing CS (only) during exercise/training/competition, which could be relevant for Sports Medicine professionals. Therefore, the purpose of this systematic review was to investigate the effect of wearing below-knee CS during exercise (or sports activity) on performance and associated physiological and perceptual indicators.
A systematic literature search was performed by two independent reviewers in PubMed. The following terms: (i) “graduated soccer cotton basketball compression sock”; (ii) “compression stockings”; (iii) “graduated compression socks”; (iv) “compression socks” were combined with “performance”, “athletes”, “exercise”, “exercise performance”, “fatigue”, “sports” and “recovery” (Figure 1).
The studies included in this review met the following inclusion criteria: 1) original studies; 2) comprised samples of adults (≥ 18 yr); 3) participants were healthy; 4) investigated the effects of wearing foot-to-knee (below knee) CS (during exercise) on exercise performance and physiological and perceptual indicators (e.g., muscle fatigue, muscle recovery, musle soreness); 5) trampoline sublimation weed white sock worn during the exercise/test/match; and 6) study protocol included exercise or effort tests and performance analysis.
The literature search occurred between January 01, 1900, until June 30, 2019. We excluded the following type of articles: conference abstracts, case reports, short communications, systematic reviews, meta-analyses, theses, letters to the editor, and protocol papers. Also, we excluded studies involving unhealthy participants: e.g., patients with morbid conditions such as obesity, chronic venous insufficiency, diabetes, hypertension (but not limited to).
The heterogeneity of the selected studies was considerable: e.g., exercise protocols, fitness level of the participants, variables measured. Thus, we have decided not to evaluate the studies chosen from a statistical point of view. Instead, we performed a qualitative analysis, conducted by two authors focusing on the effects reported by the authors and potential practical implications. All other authors read this qualitative analysis carefully, and edits have been incorporated.
Figure 1 shows the search, selection, and inclusion process. The search displayed a total of 1067 papers, which were reduced to 370 after exclusion of duplicate publications. Then, we discarded 39 articles written in non-English languages.9 From the remaining 331 items, we excluded 261 by examining the title. Finally, from the remaining 70 articles, we selected 21 studies for this review according to our inclusion criteria (Figure 1).
Table 1 presents a summary of the studies examining the effects of wearing below-knee CS during exercise on performance and associated indicators. Running was the most common type of exercise in the selected studies (76%, 16 out of the 21 studies), followed by soccer (two studies; 10%), triathlon, calf-rise exercise and cycle ergometer (one study each one; 5%). All studies were performed using a randomized experimental design, with the majority employing a crossover design strategy (13 studies, 62%) (Table 1).
Only two studies found some beneficial effect of CS on performance, and a third study improved subsequent performance (Table 2). Two studies did not find performance effects of CS for the group mean, but the authors highlighted that CS promoted benefits for some individuals. The main effects of CS are presented with compressions between 20 and 30 mmHg. The range between the anti slip wool compression sock values is 12 to 28 mmHg, while the maximum values range from 15 to 33 mmHg.