Why CrossFit May Not Work for Weight Loss

Evaluate the pros and cons of CrossFit before you begin

CrossFit weight loss
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Have you tried CrossFit for weight loss? Many CrossFit participants swear by the program’s ability to burn calories, build muscle and change your life.  The intensity of the commitment can seem cult-like.  But is Crossfit really the best choice if you want to lose weight?

Several research studies shed light on the pros and cons of the popular program for weight loss. I also spoke to Greg Zuffelato, the founder of I Believe Weight Loss.

Greg is a former CrossFit participant and CrossFit Trainer. He now coaches people to lose weight through his website and book. 

What is CrossFit?

CrossFit is a workout program, a culture, and a community.  The mission of CrossFit is to “build a program that will best prepare trainees for any physical contingency — not only for the unknown, but for the unknowable.”  In short, the CrossFit philosophy is one that employs an intense commitment to a strict workout lifestyle.

CrossFit participants complete a workout of the day (WOD) either solo or with a trainer and a group of fellow exercisers at a designated Crossfit gym or “box.”  The workouts tend to be short, extremely intense and engage full body, military-style exercises.  For participants who are interested, nutrition advice is offered on the CrossFit website where the suggestion is to follow either a 40-30-30 nutrition plan (40% carbs, 30% protein, 30% fat) or to use the Paleo Diet for best results.


Benefits of Crossfit for Weight Loss

So can CrossFit help you lose weight? “For someone strictly looking at losing weight,” says Zuffelato, "CrossFit can be an excellent program with some modifications.” Benefits of the program include:

  • CrossFit burns calories:  High-intensity workouts like CrossFit are difficult.  The American Council on Exercise (ACE) reports that men can burn 15-18 calories per minute and women can burn 13-15 calories per minute while doing the workouts.  In addition, participants who work at a high intensity burn more calories all day with EPOC.
  • CrossFit builds muscle to boost metabolism.  CrossFit participants can expect to build strength and increase muscle mass.  Greg says that the biggest change he saw when he started with CrossFit was a change in his body fat and muscle mass.  This improved body composition not only helps your body to look leaner and tighter but also helps you to maintain a healthy metabolism.
  • CrossFit community provides social support.  A key element of the CrossFit program is sharing your WOD results online or with others in your community. For many people who are trying to lose weight, this element of sharing may help improve accountability and consistency.
  • Workouts are accessible to anyone.  According to their website, CrossFit is available to “anyone with an Internet connection and the willingness, curiosity, and bravery to try it.”  Participants can work out on their own using the WOD posted on the website or they can go to a local CrossFit box. In many cities, the cost of going to a box is less than the cost of joining a full-service health club.
  • Workouts are quick and efficient.  For healthy people who already know how to perform typical CrossFit exercises, the workouts provided are both quick and effective.  If you are a busy person who is trying to lose weight with exercise, short workouts may help you keep your exercise program on track.

Why a CrossFit Weight Loss Program May Not Work

While the benefits of CrossFit may help some people lose weight and keep it off, there are drawbacks to the program that may make it the wrong choice for some people who are trying to slim down.  The problem that Zuffelato ran into after several months of doing CrossFit was injuries.  His experience is not unique according to many experts. Drawbacks of trying to lose weight with CrossFit include:

  • CrossFit drop out rate is high.  CrossFit is too intense for many people.  According to Zuffelato, “due to the high physical demand, there is a high turnover rate in CrossFit.”  In addition, ACE experts also acknowledge that you might quit because it’s too difficult.  If weight loss is your goal, then you need to find a program you can stick with for the long term. 
  • High risk for injury.  CrossFit workouts often include high-risk activities. When combined with the pressure to compete against the clock or against other athletes the exercises may put many participants at risk for injury.  Zuffelato was chronically injured and attributed his injuries to the intense program.  He did not fully recover until he backed off and allowed his body more recovery time.
  • Intense culture doesn’t work for everyone.  The competitive nature of CrossFit training may be overwhelming for some exercisers, especially those who are new to exercise.  If you are too intimidated to fully participate on a regular basis, you’re not likely to see sustainable results. 
  • Modifications may take longer to learn.  People who are new to exercise, who have not exercised regularly for a long time or have injuries to accommodate will need to modify the exercises in order to stay safe and healthy.  This may be overly time consuming.  While anyone can do CrossFit, not everyone should do CrossFit.

Can You Lose Weight with CrossFit?

If you do CrossFit consistently and with proper modifications, you are likely to see positive changes to your body.  But if you want to lose weight, you need to combine your exercise program – not matter what it is – with a good nutritional foundation. 

“The people that just do CrossFit and don’t have a nutrition plan do not lose weight,” says Zuffelato . "When they get serious with the CrossFit program their appetite goes into overdrive and without a proper plan they don’t see any sustained weight loss. They will see a small change in their body fat, but like any other exercise program, if proper nutrition is not part of the plan the results will be disappointing.”

If you are a fit, active, athletic individual who likes competition and wants to slim down then CrossFit might be the best way for you to lose weight.  But if that doesn’t describe you, chances are good that you may lose more weight if you combine a healthy diet with a moderate exercise program that is sustainable.


Gerard, Jim. " Is Any Workout Worth the Risk?." American Council on Exercise Pro Source January 2014.

Smith, Michael M.; Sommer, Allan J.; Starkoff, Brooke E.; Devor, Steven T. . " Crossfit-Based High-Intensity Power Training Improves Maximal Aerobic Fitness and Body Composition." Journal of Strength & Conditioning Research November 2013.

Fabio Comana, M.S., M.A.. " CrossFit—Is the Gain Worth the Pain? ACE Experts Weigh In." American Council on Exercise Certified News November 2010.

Pete McCall, MS. " What is CrossFit training and is it appropriate for the average person?." Fit Life April 29, 2010.

Amanda Vogel, MA. " Extreme Fitness: How Intense Is Too Intense? ." IDEA Fitness Journal February 2014.

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