Greenwood · Journal of athletic training 2003 · Open-label non-randomized cohort study · n=72

Cramping and Injury Incidence in Collegiate Football Players Are Reduced by Creatine Supplementation.

Cited 55 times in the scientific literature.

Level 3 - non-randomized controlled study

Non-randomized prospective cohort study with self-selected exposure groups

PubMed 14608430 · record verified 2026-08-26

What was done

An open-label cohort study followed 72 NCAA Division IA collegiate football players from a single team over one competitive season. Thirty-eight players volunteered to take creatine (loading dose of 0.3 g/kg/day for 5 days, then approximately 0.03 g/kg/day maintenance after activity), while 34 did not. Athletic training staff recorded treated occurrences of cramping, heat illness or dehydration, muscle tightness, muscle strains, contact and noncontact joint injuries, illnesses, and missed practices. First reported incidences were compared between groups using 2x2 chi-square tests.

What was found

Creatine users experienced significantly lower incidences than nonusers for cramping (chi2(1) = 5.35, P = .021), heat illness or dehydration (chi2(1) = 4.09, P = .043), muscle tightness (chi2(1) = 5.39, P = .020), muscle strains (chi2(1) = 5.36, P = .021), and total injuries (chi2(1) = 17.80, P < .001). No significant differences were detected for noncontact joint injuries (chi2(1) = 3.48, P = .062), contact injuries (chi2(1) = 0.00, P = .100), illness (chi2(1) = 6.82, P = .409), missed practices (chi2(1) = 1.43, P = .233), or players lost for the season (chi2(1) = 4.75, P = .491). Specific event counts and percentages were not reported in the abstract.

Why it matters

These results counter common claims that creatine supplementation causes dehydration or muscle cramping during training in warm environments, showing no elevated risk and lower rates of several soft-tissue complaints.

Limits

The study lacked randomization and blinding; players self-selected whether to ingest creatine, creating substantial risk of confounding from differences in playing time, training habits, baseline fitness, or diet. The sample was restricted to 72 male athletes from one team over a single season, and raw incidence numbers were not provided in the abstract.

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