So sánh phương pháp

	Độ trễ điện cơ	Đo lực kế đẳng tốc
Lĩnh vực	Khoa học thể thao	Khoa học thể thao
Họ	Hypothesis test	Hypothesis test
Năm ra đời	1979	1967
Người khởi xướng	Paavo Komi	Henry Hislop
Loại	EMG-force analysis	constant-velocity testing
Công trình gốc	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.
Tên gọi khác	EMD, electromechanical lag, neural delay, activation delay	isokinetic testing, constant velocity testing, dynamometric testing
Liên quan	5	5
Tóm tắt	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.