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Effect of Heat and Cold on Tendon Flexibility and Force to Flex the Human Knee
Full Title
Effect of Heat and Cold on Tendon Flexibility and Force to Flex the Human Knee
Summary
This study quantified the effects of heat and cold on knee tendon flexibility and the force required to flex the knee. Twenty male and female subjects participated in four experimental conditions: (1) room temperature, (2) cold application (ice pack for 20 min), (3) heat application (hydrocollator heat packs for 20 min), and (4) prolonged heat application (ThermaCare heat wraps for 4 hours). Ligament extensibility was measured using a KT2000 arthrometer, and the force required for knee flexion was assessed using continuous passive motion (CPM). Results showed that heat increased the flexibility of the anterior and posterior cruciate ligaments and reduced the force required for knee flexion by about 25%, while cold had the opposite effect. These findings suggest that heat therapy may enhance flexibility and reduce injury risk, whereas cold therapy may restrict movement.