CrossFit: Increased risk of injuries?
I am surrounded by naysayers. I am a professor in a Department of Nutrition & Integrative Physiology, which is a newer term used for exercise physiology. As such I am surrounded by many exercise physiologists that have pre-determined beliefs about certain types of activities. And, while high intensity interval training is well established as an effective and efficient way of increasing fitness (amongst other significant health benefits), for some reason CrossFit maintains a negative connotation. My clinical practice is in a sports medicine facility where I work with 3 sports medicine physicians, all of whom seem to think of CrossFit as an 8-letter sweat word. I also have a sister who is a physical therapist, and even after 7 years thinks I am crazy for participating in this ‘hellish’ sport. Maybe I am, but maybe not for the same reasons they believe.
Many of the above mentioned professionals – exercise physiologists, sports medicine physicians, and physical therapists – seem to have a preconception about CrossFit that it predisposes individuals to injuries, that there is a high rate of injuries among CrossFit athletes. That’s why when I saw the article by Klimek and colleagues published this year in the Journal of Sports Rehabilitation, I was intrigued. What does the science have to say?
The research design was a retrospective cohort study that reviewed any paper published in the past 10 years comparing injury rates among CrossFit participants and individuals participating in other fitness sports. Three article met the inclusion criteria, and included other sports such as gymnastics, Olympic weightlifting, military conditioning, track and field, rugby, and distance running.
What the researchers found may be of no surprise: rates of injury among CrossFit participants was equal to or lower than those of participants in the other included sports (gymnastics, Olympic weightlifting, military conditioning, track and field, rugby, and distance running). Some important notes identified in the discussion of the article include the comment that the three articles defined ‘injury’ differently; also the articles differentially defined CrossFit athletes (some were actively training with coaching/supervision, while some were engaging in CrossFit workouts but perhaps independently. One article defined types of injuries and reported that shoulder injuries were the most commonly reported injury (25%), followed by lower back (14%) and knee injuries (13%).
One article by Hak and colleagues found that 73.5% of the 132 survey respondents experienced an injury while engaging in CrossFit. The total injury rate of 3.1/1000 hours trained during CrossFit training was similar to injury rates reported in: Olympic weightlifting, gymnastics, and rugby. Sports with higher injury rates, as per report, than CrossFit include high school football, ice hockey, and soccer. It is also significant to note that the rates of injury as reported by the 3 comparison articles were all different, limiting the equality of comparison between the 3 articles. Given that the authors identified the differential criteria of ‘injuries,’ and categorized ‘CrossFit Athletes’ differently, this can be understood.
And of course I must note, this is not a free pass to neglect the importance of good form, stretching and warming up, cooling down, optimal nutrition (though I am biased on the big importance of that!), and listening to one’s body. These are all essential strategies to avoiding risk of injuries and staying safe while training.
Link to the study: https://journals.humankinetics.com/doi/pdf/10.1123/jsr.2016-0040