Creatine is well-established as safe at standard doses but has no demonstrated benefit for pure endurance performance — its plausible value for endurance athletes lies in surges/sprints and masters strength work, and the evidence specifically in women is still sparse
Interpretation
The ISSN's position stand establishes a strong safety record (up to 30g/day used safely for up to 5 years; no excess injury, cramping, dehydration or renal dysfunction at recommended doses in athletes tracked 21 months) alongside dosing guidance for its best-established benefit: high-intensity, repeated-effort capacity. Fernández-Landa et al.'s meta-analysis of 13 studies found essentially no effect on pure endurance performance (SMD -0.07, p=0.47) — the clearest evidence against using creatine as an endurance aid specifically. Tam et al.'s review of 27 studies in active women found benefit in only a minority of trials (3/11 for strength, 4/17 anaerobic, 1/5 aerobic) and explicitly calls the evidence 'inconclusive' for women — compounded by the fact only 3 of the 27 studies even collected menstrual-cycle data.
Practical implication
Don't position creatine as an endurance-performance supplement for triathletes — the meta-analytic evidence doesn't support it. Frame its plausible value around race-day surges, finishing kicks, and masters-athlete strength/lean-mass maintenance, and flag the sex-specific evidence gap explicitly rather than assuming the (mostly male) general findings transfer directly to women.
Sources
3 sources, independently verified.
The field's consensus safety and dosing statement: loading at 5g four times daily (~0.3g/kg/day) for 5-7 days, or 3g/day for 28 days, followed by 3-5g/day maintenance; doses up to 30g/day have been used safely for up to 5 years in healthy people; no evidence of increased injury, dehydration, cramping, GI upset or renal dysfunction at recommended doses in athletes tracked for 21 months. Creatine's largest, best-established benefit is for high-intensity, repeated-effort capacity, not steady-state endurance — the framing this batch's article is built around.
Pooling 13 placebo-controlled studies in trained athletes, creatine showed essentially no effect on pure endurance performance (SMD -0.07, 95% CI -0.32 to 0.18, p=0.47) — the clearest meta-analytic evidence that creatine is not an endurance-performance supplement, whatever benefit it may have for other outcomes like repeated sprints or strength.
Across 27 studies in women specifically, creatine improved outcomes in only a minority of trials — strength/power in 3 of 11, anaerobic performance in 4 of 17, aerobic in 1 of 5 — with the review's own conclusion that the overall benefit for women is 'inconclusive'. Only 3 of the 27 studies collected menstrual-cycle information, and most didn't classify reproductive status at all — the evidence gap is in the data collection itself, not just the effect sizes.