If a weightlifter performs a rapid eccentric contraction while bench pressing, which consequence is most likely in the pectoralis major muscle?

💡 Explanation

A rapid eccentric contraction lengthens the muscle while it's activated, causing significant force, and because the muscle attempts to resist this lengthening, Z-discs within sarcomeres are vulnerable to disruption, leading to muscle strain; therefore, Z-disc disruption is likely, rather than ATP production or constant sarcomere length.

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