An investigation into the use of the Functional Movement Screen as a predictor of injury in CrossFit athletes in the eThekwini municipality

Abstract

Background: CrossFit is a popular and unique exercise training programme and competition. Despite the popularity of this training programme there is a high incidence of injury amongst the athletes. The Functional Movement Screen™ (FMS™) is a pre-participation assessment which grades seven tests which screen fundamental movement patterns of athletes to possibly predict future injury. No studies have successfully looked at the use of the FMS™ to predict injury in CrossFit athletes. Aims: The aim of this study is to establish the normative values of the FMS™, which have yet to be determined for CrossFit athletes, and to determine the use of these values as a predictor for future injury. Methods: The methodology included scoring 61 CrossFit athletes using the FMS™ one month prior the “United We Stand (UWS) Games 2017”. Additionally, the athletes were required to fill out a questionnaire which was used to assess for additional risk factors for injury. The athletes were thereafter tracked documenting CrossFit specific injury over the course of the one month training period that lead up to and included participation in the “UWS Games 2017” in order to compile a injury profile. The mean FMS™ was then compared to the injuries sustained. Results: The research sample revealed that the mean FMS™ score for CrossFit athletes was 17.73 out of 21. There was no significant link between the mean value when compared to the injury rates and this was therefore not a predictor of injury. There were significant findings that showed that using components of the FMS™ as a method of injury prediction in CrossFit athletes was possible; specifically, a low trunk stability push-up test score increased the likelihood of sustaining injury and previous injury negatively impacted the shoulder mobility test. Further findings suggested that Body Mass Index (BMI) negatively impacted the performance of the FMS™, and the boxes with which the athletes were affiliated, influenced the total FMS™ scores. The most common types of injuries recorded were joint dysfunction and muscle strain and the most common locations of injury were the shoulder, knee and lower back.

Conclusions: Aspects of the FMS™ were a statistically significant predictor of injury in CrossFit athletes, specifically that of the shoulder mobility test and the trunk stability push-up test. Other findings concluded that factors such as the BMI and the box that athletes trained under influenced the FMS™ outcome. The normative value of 17.73 out of 21 for the FMS™

was provided as reference values for CrossFit athletes in order to assist with the interpretation of future scores when screening athletes.