A geriatric patient undergoes knee replacement surgery. After prolonged immobilization, which failure mode relating to sarcopenia becomes most likely during rehabilitation, even with adequate protein intake?

💡 Explanation

Prolonged immobilization post-surgery decreases muscle protein synthesis, thereby causing an imbalance favoring breakdown. Because muscle disuse accelerates sarcopenia, muscle protein breakdown is exacerbated, resulting in muscle wasting, rather than improved muscle function through neuromuscular adaptation or increased mitochondrial biogenesis.

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