International Society of Sports Nutrition Position Stand: protein and exercise.
Level 5 - mechanism / opinion, no new human data
Narrative review and society position stand representing expert consensus without systematic review methodology.
PubMed 28642676 · doi:10.1186/s12970-017-0177-8
What was done
The International Society of Sports Nutrition (ISSN) conducted an objective narrative review of literature to formulate an official position stand regarding protein intake, timing, dose, and quality for healthy, exercising individuals.
What was found
An overall daily protein intake of 1.4-2.0 g/kg/day is sufficient for most exercising individuals to build and maintain muscle mass. Higher intakes of 2.3-3.1 g/kg/day may be needed to maximize lean mass retention in resistance-trained individuals during hypocaloric periods, with novel evidence suggesting intakes exceeding 3.0 g/kg/day may promote fat mass loss. General per-serving recommendations to maximize muscle protein synthesis are 0.25 g/kg body weight or 20-40 g absolute protein containing 700-3000 mg leucine and essential amino acids, distributed every 3-4 hours. Ingesting protein before or after resistance exercise is synergistic for muscle protein synthesis, with exercise-induced anabolic sensitivity persisting for at least 24 hours, and pre-sleep casein ingestion (30-40 g) increases overnight muscle protein synthesis and metabolic rate without altering lipolysis.
Why it matters
This position stand synthesizes practical protein dosage, timing, and quality benchmarks for athletes and active individuals aiming to optimize performance, hypertrophy, and recovery.
Limits
As an expert position stand and narrative review, formal systematic search criteria, risk-of-bias grading, and meta-analytic effect sizes are not reported in the abstract. The recommendations are broad guidelines targeted at healthy exercising adults and do not apply to clinical or sedentary populations.
Cited by
- supports The RDA for protein is the amount required to prevent protein deficiency rather than the amount needed for optimal health.