The time course for elevated muscle protein synthesis following heavy resistance exercise.
Level 2 - randomized trial
Randomized within-subject controlled physiological trial
PubMed 8563679 · doi:10.1139/h95-038
What was done
Six healthy young men performed 12 sets of 6- to 12-RM elbow flexion exercises with one arm, while the contralateral arm served as an unexercised control. Muscle protein synthesis (MPS) was measured in the biceps brachii of both arms at an average of 36 hours post-exercise using primed constant infusion of L-[1,2-13C2] leucine over 11 hours.
What was found
At an average of 36 hours post-exercise, MPS in the exercised arm had returned to within 14% of the control arm value, with the difference being statistically non-significant.
Why it matters
This study delineates the duration of the post-exercise anabolic response, indicating that the marked elevation in muscle protein synthesis largely subsides by 36 hours.
Limits
The sample size was very small (n = 6) and restricted solely to healthy young men. The exercise was limited to isolated elbow flexion, and the abstract reports no data on nutritional status or earlier intermediate timepoints in this specific cohort.
Cited by
- contradicts Muscle protein synthesis peaks approximately 48 hours following resistance exercise.