Differences in Rectus Femoris Activation Among Skaters Wearing Fabric Speed Skating Suits with Different Levels of Compression

Young-Jin Moon, Joo-Ho Song, Jinny Hwang
2016 Korean Journal of Sport Biomechanics  
INTRODUCTION In a speed skating simulation study, Saetran (2008) reported that different race suits could produce a difference of 3 seconds in a 1,500-m race. Given that the difference between the first and second place in the 1,500-m final at the 2014 Sochi Winter Olympics was only 0.003 seconds (Lee et al., 2014) , the small effect of the suit and apparatus can have a major impact on the outcome of a race. Thus, the importance of sportswear is receiving increasing attention (Brownlie et al.,
more » ... 004) . As scientific and differentiated equipment reduces friction, improves motor efficiency, and has a positive impact on athletic ability, active athletes consider their personal equipment and clothing to be important, and are quick to adopt innovative, proven equipment if it could help them achieve even slightly better results. Recently, race suits for athletes have focused on the development of functional clothing that reduces muscle fatigue by limiting the size of large muscle movements during exercise. Compression clothing improves athletic performance, and alleviates post-exercise muscle pain and tissue damage. Kraemer et al. (2010) and Doan et al. (2003) reported that even simple compression stockings contribute to reducing fatigue (Berry & McMurray, 1987) and improving muscle power (Done et al., 2003). Takarada (2002) implemented blood flow restriction training in the lower limb and reported a 15% improvement in muscle strength and a 10% increase in cross-sectional muscle area. Based on the observation that compression reduces edema, and improves venous and lymphatic return, Chatham and Thomas (2013) suggested that compression improved muscle strength by increasing blood circulation. However, Ebersole (2006) found no significant differences in peak torque, total work, or peak power at different levels of compression. Thus, opinions vary on the effectiveness of compression clothing. Moreover, it has not been clearly demonstrated that compression is effective in improving athletic performance. Nevertheless, compression clothing is receiving attention worldwide from elite athletes, both in intense competitions and leisure sports (Fu et al., 2012). Efforts have been made to develop samples or products that can improve athletic performance through compression clothing. Therefore, based on a functional coated fabric applied to the femoral region of speed skating suits (developed as part of a nationally funded project to develop textiles, led by the Korea Evaluation Institute of Industrial Technology), the present study analyzed how different levels of compression affected the maximum power and activation of the rectus femoris, which produces the most power during racing, with the aim of assisting the future manufacture of speed skating suits. Objective: The purpose of this study was to investigate how different levels of compression exerted on the femoral region (known as the power zone) by coated fabric influences the activation and anaerobic capacity of the rectus femoris. Method: Three different levels of compression on the rectus femoris of the participants, namely 0% (normal condition), 9% (downsize), and 18% (downsize), were tested. The material of the fabric used in this study was nonfunctional polyurethane. Surface electromyography test was used to investigate the activation of the rectus femoris, while the isokinetic test (Cybex, 60°/sec) and Wingate test were used to investigate the maximum anaerobic power. Results: The different compression levels (0%, 9%, and 18%) did not improve the strength and anaerobic capacity of the knee extensor. However, knee flexor interfered with activation of the biceps femoris, which is an agonist for flexion, during 18% compression. Conclusion: Compression garments might improve the stretch shortening cycle effect at the time of eccentric contraction and during transition from eccentric to concentric contraction. Therefore, future studies are required to further investigate these findings.
doi:10.5103/kjsb.2016.26.4.421 fatcat:ctui4ywsfzawdkt3ilwysnwlhi