手法を比較

	等速性筋力測定	リアクティブストレングス指数
分野	スポーツ科学	スポーツ科学
系統	Hypothesis test	Hypothesis test
提唱年	1967	1987
提唱者	Henry Hislop	Marteen Bobbert
種類	constant-velocity testing	elastic response test
原典	Hislop, H. J., & Perrine, J. J. (1967). The isokinetic concept of exercise. Physical Therapy, 47(2), 114-117.	Bobbert, M. F., Huijing, P. A., & van Ingen Schenau, G. J. (1987). Drop jumping. II. The influence of dropping height on the biomechanics of takeoff after landing. Medicine & Science in Sports & Exercise, 19(4), 339-346.
別名	isokinetic testing, constant velocity testing, dynamometric testing	RSI, stretch-shortening cycle, elastic response
関連	5	3
概要	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.	The reactive strength index (RSI) is a measure of lower-body reactive strength and elastic energy utilization, calculated as jump height divided by the contact time between landing from a drop and takeoff. Introduced by Bobbert and colleagues (1987), RSI quantifies the efficiency of the stretch-shortening cycle (SSC)—the ability to rapidly switch from eccentric (lengthening) to concentric (shortening) muscle contractions. High RSI indicates rapid, forceful engagement of muscles' elastic properties (tendons, contractile proteins) and is relevant in sports requiring rapid rebound (sprinting, jumping, rebounding). RSI is trainable and sensitive to plyometric training.