REF-578 · Jäger et al. (ISSN), 2017 · Journal of the International Society of Sports Nutrition, · Paper · PubMed
ISSN Position Stand: protein & exercise
1.4–2.0 g/kg/day; ~0.25 g/kg (20–40 g) per dose every 3–4 h
Key Findings
Daily target 1.4–2.0 g/kg/day is sufficient for building and maintaining muscle mass in most exercising individuals (within the IOM Acceptable Macronutrient Distribution Range).
Higher intakes (2.3–3.1 g/kg/day) may be needed to maximise retention of lean mass in resistance-trained subjects during hypocaloric periods; novel evidence that >3.0 g/kg/day may improve body composition (fat loss) in resistance-trained individuals.
Per-dose to maximise MPS (recommendations are mixed, depend on age and recent resistance exercise): 0.25 g/kg of high-quality protein, or an absolute dose of 20–40 g; acute doses should contain 700–3000 mg leucine and/or a higher relative leucine content plus a balanced array of EAAs.
Doses ideally evenly distributed every 3–4 h across the day; timing is largely a matter of individual tolerance — benefits come from pre- or post-workout ingestion, and the anabolic effect of exercise lasts at least 24 h but diminishes with time.
Rapidly digested proteins with high EAA and adequate leucine content are most effective for MPS; whole foods can meet needs, supplementation is a practical way to ensure quality and quantity while limiting calories.
Endurance athletes: focus on adequate carbohydrate; adding protein may offset muscle damage and promote recovery. Pre-sleep casein 30–40 g increases overnight MPS and metabolic rate without affecting lipolysis.
Practical Application
ISSN position stand (2017): 1.4–2.0 g/kg/day of protein is sufficient for most exercising people; per dose 0.25 g/kg (20–40 g) with 700–3000 mg leucine, evenly every 3–4 h; 2.3–3.1 g/kg/day during a hypocaloric phase in resistance-trained athletes; 30–40 g casein before sleep raises overnight MPS.
Set daily protein inside the 1.4–2.0 g/kg/day band in hard training; the base defaults to the upper part of it (not from this paper; the base's own practice, informed by the ~1.6 g/kg/day breakpoint in REF-579). During a deficit/weight cut, push higher (2.3–3.1 g/kg/day) to protect lean mass.
Prescribe ~0.25 g/kg (≈20–40 g) leucine-rich protein per occasion every 3–4 h — not 1–2 boluses. Inference, not tested: across a waking day that is about 4–5 feedings.
Anchor all per-meal/pre-sleep protein advice to this stand.
Limitations
Consensus, not primary data; the band is a population range varying with energy balance, load, age.
How this entry was checked and changed
Why this level
regraded 2026-09-27 from B: major position statement (rubric: consensus / position statement = A)
Content correction 2026-09-27
"1.6–2.0 g/kg/day" and "4–5 feedings" were presented as the stand's numbers -> the stand says 1.4–2.0 g/kg/day and "every 3–4 h"; house numbers labelled as the base's practice / inference. Added the 2.3–3.1 g/kg/day hypocaloric recommendation and the 24-h anabolic window from the abstract.
Level B -> A per rubric (major position statement). Cross-references given refIds.