All subjects performed quadriceps maximal voluntary contraction(MVC) and fastest speed leg extension with different levels(75%,60%,45% 1RM),and 45% fatigue test to all-out.

• 受试者实施股四头肌最大等长收缩、最快速度不同强度(75%25、60%25、45%251 RM)的伸膝动作及45%25的疲劳测试,记录向心期不同强度的MMG讯号。