مقایسهٔ روش‌ها

	نرخ توسعه نیرو	Electromechanical Delay
حوزه	علوم ورزشی	علوم ورزشی
خانواده	Hypothesis test	Hypothesis test
سال پیدایش	2002	1979
پدیدآور	Peter Aagaard	Paavo Komi
نوع	isometric force measurement	EMG-force analysis
منبع بنیادین	Aagaard, P., Simonsen, E. B., Andersen, J. L., Magnusson, P., & Dyhre-Poulsen, P. (2002). Increased rate of force development and neural drive of human skeletal muscle following resistance training. Journal of Applied Physiology, 93(3), 1318-1326.	Cavanagh, P. R., & Komi, P. V. (1979). Electromechanical delay in skeletal muscle under normal movement conditions. Acta Physiologica Scandinavica, 106(3), 241-248.
نام‌های دیگر	RFD, explosive strength, force development rate, strength impulse	EMD, electromechanical lag, neural delay, activation delay
مرتبط	5	5
خلاصه	Rate of force development (RFD) is the speed at which force is produced during the initial phase of muscle contraction, typically expressed as the slope of the force-time curve in the first 50, 100, or 200 milliseconds of isometric contraction. Introduced comprehensively by Aagaard and colleagues (2002), RFD is a measure of explosive strength capacity and neural drive efficiency. Unlike maximal voluntary strength (which captures peak force), RFD captures how quickly an athlete can generate that force—a critical quality in sports requiring rapid, explosive movements (sprinting starts, jumping, tackling). RFD improves dramatically with strength training, reflecting increased motor unit recruitment rate and firing frequency.	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.