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Plyometric Exercise Causes Type II Muscle Fiber Damage
Full Title
Type II Muscle Fiber Damage From Plyometric Exercise
Summary
This study examined the effects of a single bout of lower-body plyometric exercise on muscle damage in resistance-trained individuals. Muscle biopsies were taken before and 24 hours after 10 sets of 10 maximal squat jumps. Results showed significant ultrastructural muscle damage, especially in type II (fast-twitch) fibers. Serum creatine kinase (CK) levels also increased, and muscle soreness and strength loss were reported post-exercise. The study confirms that plyometric exercise can induce high levels of mechanical stress and functional impairment in skeletal muscle, particularly in fast-twitch fibers most responsible for power movements.