方法对比

	机电延迟	等速测力法
领域	体育科学	体育科学
方法族	Hypothesis test	Hypothesis test
起源年份	1979	1967
提出者	Paavo Komi	Henry Hislop
类型	EMG-force analysis	constant-velocity testing
开创性文献	Cavanagh, P. R., & Komi, P. V. (1979). Electromechanical delay in skeletal muscle under normal movement conditions. Acta Physiologica Scandinavica, 106(3), 241-248.	Hislop, H. J., & Perrine, J. J. (1967). The isokinetic concept of exercise. Physical Therapy, 47(2), 114-117.
别名	EMD, electromechanical lag, neural delay, activation delay	isokinetic testing, constant velocity testing, dynamometric testing
相关	5	5
摘要	Electromechanical delay (EMD) is the time interval between electrical muscle activation (detected via electromyography) and the first detectable mechanical force output. Introduced by Cavanagh and Komi (1979), EMD reflects the physiological lag inherent in converting neural input into mechanical work. This delay arises from several sources: time for the action potential to propagate, time for calcium release, time for cross-bridge cycling to begin, and elastic recoil of muscle-tendon structures. EMD is typically 30-100 milliseconds in skeletal muscle and varies with muscle group, contraction type, and training status. Understanding EMD is important for explaining performance in rapid movements and for assessing neuromuscular function.	Isokinetic dynamometry measures muscular strength and power production during movement at a constant, preset velocity. Pioneered by Hislop and Perrine (1967), isokinetic testing constrains limb velocity to a fixed speed (e.g., 60°/s or 120°/s), while the dynamometer adjusts resistance to match the subject's force production at each instant, accommodating all variations in force throughout the range of motion. This approach provides comprehensive strength profiling across a full joint range and allows comparison of concentric and eccentric contractions. Isokinetic testing is widely used in clinical rehabilitation, sports medicine, and research due to its objectivity and standardization.