Risk Factors for Exercise-Associated Muscle Cramps: A Systematic Review With Meta-Analysis.

INTRODUCTION/AIMS: Exercise-associated muscle cramps (EAMC) are common in athletic populations and are frequently cited as a factor limiting performance. Despite extensive investigation, uncertainty remains regarding the risk factors associated with EAMC. Therefore, the aim of this systematic review was to identify and synthesize the available evidence on potential risk factors for EAMC. METHODS: A systematic search was conducted in MEDLINE, EMBASE, Web of Science, SPORTDiscus, and CINAHL from inception to April 2026. Longitudinal studies that followed participants over any period to assess the occurrence of EAMC were included. RESULTS: Of 14,181 records, nine studies were included (n = 11,274 participants). Across 36 meta-analyses, only three variables demonstrated statistically significant associations with EAMC. A prior history of EAMC was associated with subsequent episodes, conferring approximately 4.4-fold higher odds of EAMC occurrence (strong evidence). Higher post-race serum potassium (moderate evidence) and magnesium (limited evidence) concentrations were also observed in individuals with EAMC. Strong evidence indicated no associations between EAMC and age, body mass, or height. No other consistent results were identified across anthropometric, demographic, hydration, metabolic, performance, practice, routine, or training domains. DISCUSSION: The association with prior EAMC history supports the concept of a recurrent phenomenon. This suggests that EAMC may be driven primarily by individual history rather than by commonly investigated physiological or training-related factors. The uncertainties regarding hydration status, electrolyte balance, training load, and performance challenge traditional preventive paradigms. However, given that most findings were supported by limited or very limited evidence, further high-quality research is warranted. TRIAL REGISTRATION: PROSPERO: CRD420251061240.