Compression Garments, Muscle Contractile Function, and Economy in Trail Runners

Background: Physiological mechanisms behind the use of compression garments (CGs) during off-road running are unknown. Purpose: To investigate the influence of wearing CGs vs conventional running clothing (CON) on muscle contractile function and running economy before and after short-distance trail running. Methods: Knee-extensor neuromuscular function and running economy assessed from two 5-min treadmill runs (11 and 14 km/h) were evaluated before and after an 18.6-km short-distance trail run in 12 trained athletes wearing either CGs (stocking + short-tight) or CON. Quadriceps neuromuscular function was assessed from mechanical and EMG recording after maximal percutaneous electrical femoral-nerve stimulations (single-twitch doublets at 10 [Db 10 ] and 100 Hz [Db 100 ] delivered at rest and during maximal quadriceps voluntary contraction [MVC]). Results: Running economy (in mL O 2 · km –1 · kg –1 ) increased after trail running independent of the clothing condition and treadmill speeds ( P < .001). Similarly, MVC decreased after CON and CGs conditions (–11% and –13%, respectively, P < .001). For both clothing conditions, a significant decrease in quadriceps voluntary activation, Db 10 , Db 100 , and the low-to-high frequency doublet ratio were observed after trail running (time effect, all P < .01), without any changes in rectus femoris maximal M-wave. Conclusions: Wearing CGs does not reduce physiological alterations induced during short-distance trail running. Further studies should determine whether higher intensity of compression pressure during exercises of longer duration may be effective to induce any physiological benefits in experienced trail runners.