Background: This study examined the effects of different levels of compression (0, 20 and 40 mmHg) produced by\r\nleg garments on selected psycho-physiological measures of performance while exposed to passive vibration (60 Hz,\r\namplitude 4-6 mm) and performing 3-min of alpine skiing tuck position.\r\nMethods: Prior to, during and following the experiment the electromygraphic (EMG) activity of different muscles,\r\ncardio-respiratory data, changes in total hemoglobin, tissue oxygenation and oscillatory movement of m. vastus\r\nlateralis, blood lactate and perceptual data of 12 highly trained alpine skiers were recorded. Maximal isometric knee\r\nextension and flexion strength, balance, and jumping performance were assessed before and after the experiment.\r\nResults: The knee angle (-10�°) and oscillatory movement (-20-25.5%) were lower with compression (P < 0.05 in\r\nall cases). The EMG activities of the tibialis anterior (20.2-28.9%), gastrocnemius medialis (4.9-15.1%), rectus femoris\r\n(9.6-23.5%), and vastus medialis (13.1-13.7%) muscles were all elevated by compression (P < 0.05 in all cases).\r\nTotal hemoglobin was maintained during the 3-min period of simulated skiing with 20 or 40 mmHg compression,\r\nbut the tissue saturation index was lower (P < 0.05) than with no compression. No differences in respiratory parameters,\r\nheart rate or blood lactate concentration were observed with or maximal isometric knee extension and flexion\r\nstrength, balance, and jumping performance following simulated skiing for 3 min in the downhill tuck position\r\nwere the same as in the absence of compression.\r\nConclusions: These findings demonstrate that with leg compression, alpine skiers could maintain a deeper tuck\r\nposition with less perceived exertion and greater deoxygenation of the vastus lateralis muscle, with no\r\ndifferences in whole-body oxygen consumption or blood lactate concentration. These changes occurred without\r\ncompromising maximal leg strength, jumping performance or balance. Accordingly, our results indicate that the\r\nuse of lower leg compression in the range of 20-40 mmHg may improve alpine skiing performance by allowing a\r\ndeeper tuck position and lowering perceived exertion.
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