Question

Growing evidence reveals that, independent of resistance exercise, ____________ can activate mTOR and promote small increases in muscle protein synthesis.

Answer 1

β-hydroxy β-methylbutyrate (HMB) can activate mTOR and promote small increases in muscle protein synthesis. HMB enhances gains in muscle size, strength, and lean body mass while reducing exercise-induced muscle damage and promoting recovery. The timing of HMB ingestion relative to exercise affects its effectiveness.

Step-by-step explanation:

Growing evidence reveals that, independent of resistance exercise, β-hydroxy β-methylbutyrate (HMB) can activate mTOR and promote small increases in muscle protein synthesis. HMB is a dietary supplement that has been shown to enhance gains in muscle size, strength, and lean body mass, while reducing exercise-induced muscle damage and promoting recovery from high-intensity exercise. It achieves these effects by stimulating muscle protein synthesis and inhibiting muscle protein breakdown through the activation of mTOR and inhibition of the proteasome in skeletal muscles.

HMB's effectiveness is influenced by the timing of its ingestion relative to exercise. The greatest reduction in skeletal muscle damage occurs when calcium HMB is taken 1-2 hours before exercise.