The epidemiology, clinical characteristics and associated risk factors of injuries in crossfit athletes : a prospective cohort study

Abstract

Background: CrossFit is a type of high-intensity training that includes aerobic exercises, gymnastics, powerlifting and Olympic-style weightlifting. CrossFit is a rapidly growing exercise regime associated with high injury rates. There is insufficient literature regarding risk factors for injury amongst CrossFit athletes, with few prospective cohort studies reported globally.

Objective: To determine the epidemiology, clinical characteristics and associated risk factors for injuries in adult CrossFit athletes training at a box in Pretoria, South Africa.

Methods: Prospective cohort study among 48 participants (males n = 20 (41.7%), females n = 28 (58.3%)), followed over 12 weeks. A modified Olso Sports Trauma Research Centre Questionnaire for Health Problems (OSTRC-H2) was used biweekly to capture self-reported CrossFit-related injury (CRI) and training data.

Results: Overall, 24 injuries were sustained by 18 participants. We reported an overall mean injury prevalence of 37.5%, a mean injury prevalence per two-week period of 19.4%, and a mean injury rate of 0.26 injuries per 1000 hours of CrossFit exposure. Females sustained a higher injury rate than males (0.29 vs 0.22 injuries per 1000 hours). The leading anatomical sites of CRIs involved the shoulder (41.7%), lumbosacral spine (20.8%) and knee (8.3%). The most commonly injured tissues included muscle (41.79%), followed by synovium/capsulitis (16.7%) and tendinopathies (12.5%). Half the reported injuries did not result in days lost from CrossFit participation (50.0%), and a history of a previous CRI in the past six months was an independent risk factor for obtaining a current CRI.

Conclusion: Approximately one in three CrossFit athletes sustained a CRI affecting mainly the shoulder, lumbar spine and knee. A previous injury in the past six months is a significant risk factor for sustaining a new CrossFit injury. A combination of clinical knowledge, experience, and the results of this study could assist in developing future injury prevention strategies among CrossFit athletes.