Males, older age, increased training, chronic diseases, allergies, and history of injury are independent risk factors associated with a history of exercise-associated muscle cramping in distance runners in 76 654 race entrants - SAFER XXIX

Abstract

OBJECTIVE :

To determine independent risk factors associated with a history of exercise-associated muscle cramps (hEAMCs) in distance runner race entrants in a community-based mass participation event. DESIGN :

Cross-sectional study. SETTING :

2012 to 2015, Two Oceans marathon races (21.1 and 56 km), South Africa. PARTICIPANTS :

Seventy six thousand six hundred fifty-four consenting race entrants. ASSESSMENT OF RISK FACTORS :

Entrants completed an online prerace medical screening questionnaire as part of the entry process. In a multiple model, sex, age, training variables, history of chronic disease, allergies, and running injuries were included as potential factors associated with hEAMC in 21.1 and 56 km entrants. MAIN OUTCOME MEASURES :

Prevalence (%) and prevalence ratios (PRs, 95% confidence intervals) are reported. RESULTS :

Men (P < 0.0001) and older age (>40 years, P < 0.0001) were significantly associated with hEAMC. Therefore, the model was adjusted for sex and age group and run separately for 21.1- and 56-km entrants. Specific independent risk factors associated with hEAMC in 21.1- and 56-km entrants were: a history of chronic diseases (21.1 km: PR = 1.9; 56 km: PR = 1.6; P < 0.0001), running injury in the last 12 months (21.1 km: PR = 1.7; 56 km: PR = 1.4; P < 0.0001), history of allergies (21.1 km: PR = 1.4; 56 km: PR = 1.2; P < 0.0001), and various training variables (PR = 1.0-1.1). CONCLUSION :

In 21.1- and 56-km race entrants, independent risk factors associated with hEAMC were men, older age, longer race distances, training variables, chronic diseases, history of allergies, and history of a running injury in the past 12 months.