Updated: Apr 18, 2020
CrossFit is polarizing: you either love it or you hate it. It is like trying to get a New Yorker and a Chicagoan to agree about pizza. Is deep dish really pizza or is it tomato soup with a bread bowl? Is it delicious? Yes... but as someone who grew up in Upstate New York it is hard to compare the two. We can all agree that pizza is delicious regardless. Our exercise regimen and our fitness goals are similar to pizza in that it comes down to personal preference.
CrossFit has received this perception that it has a high injury rate, which makes people hesitant to join. My goal with this post is to present to you the research that has been done on CrossFit and how it compares to other recreational activities.
What is CrossFit?
CrossFit defines itself as "a lifestyle characterized by safe, effective exercise and sound nutrition. CrossFit can be used to accomplish any goal, from improved health to weight loss to better performance. The program works for everyone - people who are just starting out and people who have trained for years." CrossFit believes that its methodology works because the workouts are constantly varied, it uses functional movements that translate to every day life, and the workouts are high intensity but can be scaled to each individual.
CrossFit combines cardiovascular exercises, gymnastic movements, and olympic weightlifting into their workout programs. The traditional cardiovascular exercises include running, biking, rowing, etc. Gymnastic movements include movements like handstand walking and muscle ups using a bar or rings. Olympic weightlifting includes movements such as the clean, the jerk, and the snatch. A CrossFit class typically includes a warm-up, a strength component, and then the workout of the day (WOD). The WODs are constantly varied and are designed to test power, strength, and cardiovascular endurance.
Argument Against CrossFit
The argument against CrossFit starts with its unorthodox training approach. Montalvo et al. (2017) stated that "WODs typically mix aerobic and anaerobic exercises with high skill movements, including jerks, snatches and muscle-ups, which are performed under cardiovascular and muscular fatigue conditions". In traditional strength training, highly skilled movements and multi-joint movements are performed first to limit fatigue and preserve technique. In CrossFit, WODs are the last part of a class and the class is structured this way so athletes can give their max effort and compete during the WOD.
CrossFit's safety has been questioned due to these highly skilled and high intensity anaerobic movements being performed underneath fatigue. The fatigue may disrupt technique and concentration putting that athlete at a greater risk of injury. However, despite these safety concerns there has been little evidence that has either supported or denied these claims.
Injury Incidence vs. Injury Rate
The first thing that should be addressed is differentiating between injury incidence vs. injury rate. Injury incidence is the number of injuries experienced within a given amount of time while participating in CrossFit. Injury rate is the number of injuries per 1000 hours of CrossFit exposure.
Feito et al. (2018)
Injury Incidence = 931 out of 3049 (30.5%) experienced an injury over the previous 12 months. 62.4% reported a single body part injury & 37.6% injured multiple body parts.
Injury Rate = It ranged depending on engagement and experience, 0.27-0.74 injuries per 1000 training hours. The more engaged & experienced CrossFitters had a lower injury rate.
Mehrab et al. (2017)
Injury Incidence = 252 out of 449 (56.1%) reported experiencing injury within the last 12 months, 15.2% sustained > 2 injuries
Montalva et al. (2017)
Injury Incidence = 50 out of 191 (26.1%) athletes sustained a total of 62 injuries over 6 months
Injury Rate = 2.3 injuries per 1000 training hours
Moran et al. (2017)
Injury Incidence = 15 out of 117 (12.8%) experienced time-loss injuries over the 12 weeks
Injury Rate = 2.1 injuries per 1000 training hours
Weisenthal et al. (2014)
Injury Rate = 75 out of 386 (19.4%) experienced 1 injury within the last 6 months
Take a deep breath, I know that was a lot of information to digest. Small PSA, don't be the guy in the pic above who doesn't put away his weight. What a slob! Anyway, I think we need to compare how CrossFit compares to other sports.
In a 1993 study that looked at recreational sports injuries, they followed 986 participants over a 3 month span. The recreational sports included running, weight lifting, cardiovascular fitness activities, and competitive sports. This study reported that there was an injury rate of 7.83 per 1000 training hours. (Requa et al. 1993)
In a much more recent 2014 study about dragon boat racing (It is an up and coming sport and I highly suggest trying it), they reported an injury rate of 3.82 per 1000 training hours. (Mukherjee et al. 2015)
In a 2015 systematic review, it looked at running related injuries per 1000 hours of running. The injury rates ranged from 2.5 injuries per 1000 hours in long distance track and field athletes to as high as 33 injuries per 1000 hours for novice runners. (Videbæk et al. 2015)
CrossFit injury rate ranged between 0.27-2.3 injuries per 1000 training hours, which is comparable to other recreational sports. The injury incidence ranged between 12.8% to 56.1% but those studies ranged from 12 weeks to 12 months. The higher injury incidence was correlated with a higher study duration. If you consider that a consistent CrossFitter typically workouts 4-6x per week, the likelihood of experiencing an injury over an extended period of time goes up. Mehrab et al. (2017) stated that athletes reported that if they needed to modify CrossFit workouts for more than 2 weeks, it meant that the injury would not heal without medical attention.
Who Gets Injured in CrossFit?
CrossFit injury rate has been shown to be inversely related to experience. Feito et al. (2018) concluded that "there are 3 main groups that are at a greater risk for injuries, those who (1) are within their first year of participation, (2) engage in this training modality less than 3 days per week, (3) participate in less than 3 workouts per week."
Weisenthal et al. (2014) found that there were no difference in injury rates for athletes when comparing various ages and when looking at the length of the training session. Males were more likely to be injured than females and females were more likely to seek coach supervision. This may be due to males focusing more on performance rather than technique. Once they lift heavier loads and their technique becomes more compromised, the likelihood of injury increases.
Moran et al. (2017) also found that there was a higher injury rate in males. They also noted a high injury rate for participants with a previous injury within the past 6 months and participants that had more asymmetries on the functional movement screen.
Argument for CrossFit
CrossFit injury rate has been shown to be consistent with other recreational sports. I believe that the hesitancy to join is due to preconceived notions that may be a result of a study in 2013 by the NSCA stating that CrossFit had a high risk of overuse injuries. However, CrossFit just recently won a lawsuit in 2019 that showed NSCA fabricated and falsified data. I also think that the CrossFit games can make CrossFit seem intimidating. People may think it is only for the elite athletes and are unaware that each exercise can be modified specific to them.
I think the biggest argument that CrossFit has going for it is the sense of community that it creates. There is a camaraderie that develops between people when they complete a challenging workout together. CrossFit members report experiencing a significantly greater bond and community belongingness compared to traditional gym members. This cohesion may contribute to exercise adherence, which might explain CrossFit's effectiveness. (Montalva et al. 2017) My personal belief is that consistency is more important than methodology to get results. CrossFit has done a great job building community and creating accountability for its members. Injuries occur with novice CrossFitters most likely due to not being as technically sound with the CrossFit lifting techniques and not scaling appropriately. I believe this can be combated with good coaching. Males need to keep their ego in check and focus on proper form prior to trying to lift heavy weight. Technique should be emphasized initially more than performance. I think a good rule of thumb for CrossFitters is that if an injury causes workout modification or cessation lasting greater than 2 weeks, they should seek medical attention.
My final thought is that we should not bash any exercise regimen because we need to promote movement. America's biggest problem as a society is that we do not move enough, which is evident by the amount of obesity in this country. Obesity leads to diabetes, heart disease, stroke, and increased risk of certain types of cancer. These are preventable diseases and our initiative should be to get people moving regardless of the avenue that they chose.
Videbæk S., Bueno A.M., Nielsen R.O., Rasmussen S. Incidence of running-related injuries per 1000 h of running in different types of runners: A systematic review and meta-analysis.Sports Med.2015;45:1017–1026. doi: 10.1007/s40279-015-0333-8