Some thoughts on CrossFit
CrossFit is a very prominent fitness trend that continues to grow in popularity. CrossFit workouts of the day include exercises with high power outputs, multi-joint compound exercises, gymnastic bodyweight moves, and minimal rest periods (Smith, Sommer, Starkoff, & Devor, 2013). I conceptualize CrossFit as a sport and not as a progressive exercise training program. CrossFit is an intense physical activity, that has helped some people improve their function and health, but it does not necessarily follow exercise science principles and may have an unseemly high rate of injury compared to safe fitness programs.
CrossFit can help people improve their fitness level. Smith et al. (2013) found significant increases in VO2 max and improvements in body composition over a 10 week period. Strength performance was found to have increased in the exercises of pushups, squats, sit-ups, deadlifts, and military presses (Knapik, 2015). CrossFit can yield positive fitness results for some clients.
CrossFit is not based on scientific principles and may have a higher rate of injury than traditional training modalities. Many CrossFit workouts ignore the training principles of progressive overload and individualization wherein training intensity, frequency, and overall volume are systematically altered to optimize positive change with mindful attention to the needs, goals, limitations, and adaptive abilities for participants (Mullins, 2015). CrossFit uses high volume- high rep ranges, with exercises, like a clean and jerk, that require technical proficiency. In a large group setting with focus on getting the exercises done as quickly as possible, improper form is used decreasing benefits and increases the chances of injury (Mullins, 2015).
People who do CrossFit tend to get injured. Anecdotally, everyone I know who has done Crossfit for an extended period have gotten hurt. In a 6 month study 50/191 (26%) Crossfit participants reported an injury, with the most common site of injury being the shoulders, knee, and lower back, and increased length of CrossFit participation and training frequency being correlated with a higher frequency of injury (Montalvo et al., 2017). When compared to other sports, the injury rate is similar if not slightly lower. However, one of the primary goals of an exercise training program is to minimize injury risk. CrossFit can overload the body through technically demanding lifts that are not properly individualized and poorly supervised, can lead to injury.
I conceptualize CrossFit as a sport due to the existence of competitions, the athleticism involved, and most high level participants are in great physical condition. It is not a training program as there is a high rate of injury and it does not follow exercise science principles. If it works for some people that’s great, but I wouldn’t recommend it for deconditioned people or novice exercisers.
Knapik, J. J. (2015). Extreme conditioning programs: Potential benefits and potential risks. Journal of Special Operations Medicine, 15(3), 108-113.
Montalvo, A. M., Schaefer, H., Rodriguez, B., Li, T., Epenere, K., & Meyer, G. D. (2017). Retrospective injury epidemiology and risk factors for injury in CrossFit. Journal of Sport Science & Medicine, 16(1), 53-59.
Mullins, N. (2015). CrossFit: Remember what you have learned; Apply what you know. Journal of Exercise Physiology Online, 18(6), 32-46.
Smith, M. M., Sommer, A. J., Starkoff, B. E., & Devor, S. T. (2013). Crossfit-based high-intensity power training improves maximal aerobic fitness and body composition. Journal of Strength and Conditioning Research, 27(11), 3159-3172.