Which statement best describes mTOR's role in exercise signaling?

• A. mTOR inhibits protein synthesis
• B. mTOR promotes increased translation that results in increased protein synthesis
• C. mTOR is involved in antioxidant enzyme regulation
• D. mTOR decreases translation efficiency

Answer: (B)

mTOR functions as a central regulator that translates an exercise signal into muscle growth by boosting protein production. When resistance exercise activates the signaling pathways and nutrients are available, mTOR complex 1 (mTORC1) becomes active and drives the translation machinery forward. It does this by phosphorylating targets like S6K1 and 4E-BP1, which removes the brakes on translation initiation and promotes ribosome activity, leading to more protein synthesis. This increase in translational capacity and efficiency supports muscle protein accretion and hypertrophy in response to training.

So the best description is that mTOR promotes increased translation that results in increased protein synthesis. It does not inhibit protein synthesis, nor is its primary role antioxidant enzyme regulation, and it does not decrease translation efficiency.