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How To Lose Weight With CrossFit

Updated: Jan 18, 2023

Losing weight can be tough. Dieting and exercise can often be really intimidating to those who are starting out. Even if you are already a CrossFit athlete but want to shed a few pounds of body fat, it can be hard.

To learn how to lose weight with CrossFit you need to look at how the body works and how you can follow a simple equation to lose weight.

CrossFit Dumbell Snatch
CrossFit Dumbell Snatch

Losing weight is as simple as calories in vs calories out. You need to burn more calories than you consume to generate a calorie deficit.

If you sustain a calorie deficit, you will lose weight. It is as simple as that.

This blog takes a deeper dive into these two aspects of losing weight and how CrossFit can help you lose weight, by using it as a tool for calorie burning, adherence and behaviour changing.

It can be really hard to lose weight, especially in office jobs or routines where exercise is minimal and its hard to make the right dietary decisions. Losing weight doesn't have to be too hard and can actually be fun.

We recommend that if needed you contact a dietition, coach or gym to get started on your weight loss journey!

Losing Weight With CrossFit Diet

When we look at what we consume, i.e. calories in, we look at what we eat and drink.

CrossFit athletes love to use their workouts as an excuse to eat more, but to lose weight we need to maintain a calorie deficit. To work out how much we need to eat we need to predict how many calories we need to consume to maintain a deficit.

To do this we need to work out two things, our Basal Metabolic Rate and how many calories we burn throughout the day.

Your Basal Metabolic Rate is the amount of calories you burn in a day doing absolutely nothing. If you were laid in your bed and didn't move, how many calories would it take to keep you alive. You can predict your basal metabolic rate accurately by using machines such as an Inbody which gives you an in-depth analysis of your body composition or you can get a less accurate result by using online calculators like this one.

CrossFit Athlete - How to lose weight in CrossFit
CrossFit Athlete - How to lose weight in CrossFit

Once you have your BMR you then need to add on how many calories you think you burn in a day, you can again do this on online calculators, calorie burning trackers like fitness watches or heart rate bands (although studies show that these typically over estimate calories up to 20%) or going into a lab and calculating the rate at which you burn calories.

Once you have these two things you can add them together and define how many calories you burn every day. You then need to decide how quickly you want to lose weight and calculate your caloric needs for the day. again online calculators are a great way of doing this.

How many calories do I need to eat to lose weight with CrossFit?

To put this in perspective, 7,700 calories equals 1kg of weight loss. So if you wanted to lose 5kg of weight in 5 weeks that is a caloric deficit of 1,100 calories every day for 5 weeks. This is where losing weight gets challenging.

Once you decide how many calories you need to eat to lose weight, you need to stick to that. In can be very challenging to stick to a number that is very low to start with. Say you don't do any exercise whatsoever and your caloric needs are around 2,000 calories a day and you want to lose 1kg a week, you can only consume 900 calories a day. For almost everyone this will be a challenge, battling hunger will be a huge feat.

This is where using CrossFit as a tool to manage your diet can really help. If you introduce exercise into your weight-loss programme you can afford yourself more calories to consume, whilst also burning more calories throughout the day.

The same can be said for any exercise regime, but CrossFit can also help in other ways too.

Losing weight with CrossFit Workouts

CrossFit is an exercise programme that often includes high intensity workouts that require a lot of calories to burn, the main reason CrossFit sets itself apart from other exercise programmes and can help you lose weight even faster is the overwhelming sense of community paired with these high quality CrossFit workouts.

CrossFit boxes and workouts have an incredible social aspect to them. CrossFit mainly runs classes with people of all abilities, races, ages, sexes, genders etc all doing the same workout together.

CrossFit Community
CrossFit Community

Not only do you workout with these people, but they are genuinely invested in your welfare. Other CrossFit athletes will cheer you on, encourage you and wait for everyone in the class to finish the workout before leaving. You may not find this in any other sport around the world, where competitors actively cheer others on.

With a renewed focus on inclusivity and diversity, CrossFit HQ has over the past 5 years encouraged different countries from around the globe to compete in the Open. A worldwide, online event that pits every CrossFitter against each other with 5 workouts over 5 weeks. An event like no other in any sport.

Although competitors, this annual event shows the nature of CrossFit, every gym will cheer each member on to try and complete the event to the best of their ability, no matter if they are competing in the same category or not.

What are the benefits of losing weight with Crossfit?

CrossFit is a high-intensity, functional fitness program that can be an effective way to lose weight and improve overall fitness. Here are some of the benefits of losing weight with CrossFit:

  1. High-intensity workouts: CrossFit workouts are designed to be intense and challenging, which means that you can burn a lot of calories in a short period of time. This can help you lose weight quickly and efficiently.

  2. Whole-body workouts: CrossFit workouts typically involve a combination of cardio, strength training, and gymnastics movements. This means that you are working out your entire body and burning calories from different muscle groups.

  3. Variety: One of the benefits of CrossFit is that the workouts are varied and constantly changing, this keeps things interesting and prevents boredom. The variety also keeps your body guessing and help you to keep burning calories even after the workout.

  4. Stronger muscles: CrossFit workouts are designed to build strength and muscle mass, which can help you burn more calories even when you're not working out.

  5. Increased metabolism: High-intensity exercise like CrossFit can increase your metabolism, which means that you'll burn more calories throughout the day.

  6. High-energy community: CrossFit workouts are typically done in a group setting, which can help you stay motivated and accountable. The supportive and competitive environment can also help you push yourself harder and burn more calories.

  7. Improved overall fitness: CrossFit can help you lose weight, but it also focuses on overall fitness, which includes cardiovascular and respiratory endurance, stamina, flexibility, power, speed, coordination, agility, balance, and accuracy.

It's important to note that CrossFit is intense and not for everyone. It's always a good idea to check with your doctor before starting a new exercise routine, especially if you have any pre-existing health conditions. It is also recommended to start with lower intensity and gradually increase it as you get more comfortable and stronger.

Are there different types of CrossFit workouts?

Yes! CrossFit all about preparing for literally everything so it is common to see a wide variety of workouts at your CrossFit gym. This can include short sprint workouts, strength workouts, longer endurance type workouts and more.

The classic CrossFit workouts usually sit at around 10-15 minutes with a full range of movements usually in a couplet or a triplet. For example, FRAN is 21-15-9 of Thrusters and Pull ups and although the high level athletes complete FRAN in under 2 minutes it takes the average crossfitter around 8-12 minutes.

A classic rep scheme and a classic couplet FRAN is a brutal, unforgiving workout but hey it sure burns a heck of a lot of calories. Also, workouts like this leave you burning more and more calories throughout the day. As your body works to recover, you burn more and more calories.

The best way to lose weight with CrossFit: Adherence!

With this community comes one of the biggest and most important factors of losing weight; Adherence. If you can stick to your caloric deficit you will lose weight.

If you attend a class where the coaches and members are actively invested in your welfare and your goal to lose weight, you are more likely to stick to your diet or exercise programme than if you were trying on your own.

This culture actively promotes a healthy lifestyle, no matter at what level you are.

Losing weight with CrossFit is made easier by the community you surround yourself with, as well as the numerous benefits the exercise programme gives you.

Staying consistent with your training and with your diet is the most difficult but will do the most for losing weight and your goals.

Whether it is making sure you steer clear from the cookie jar in the evenings or turn up to the gym early every day, consistency is THE key to your fitness goals.

Can CrossFit Classes help me lose weight?

CrossFit is based around health, and thus so promotes functional fitness. In doing so CrossFit programmes functional fitness movements, like clean and jerks, running or suitcase deadlifts.

[Want to learn more about functional fitness? Check out our guide to what is Functional Fitness here.]

The range of different movements, helps develop muscle, strength and cardiovascular abilities to help athletes cope with the requirements of normal life. Lifting a child off of the floor, putting heavy books on top of a bookcase or even getting up out of the arm chair.

CrossFit Lifter
CrossFit Lifter

With these movements and workouts, you will no doubt burn more calories than not doing CrossFit. When losing weight this will help you create more of a caloric deficit and help you lose weight faster, and have fun with friends whilst doing it.

Classes also really depend on your coach too. If there is a particular class with a particular coach that really motivates you to lift more or to follow your fitness goals then make every effort to do more classes with them. The same is true for a toxic coach who you don't get on with... you know the ones I mean.

Why am I not losing weight with CrossFit?

Losing weight is really tough. Don't be disheartened if your journey takes time, especially if you are in good shape already. Losing that extra 1% of body fat when you're below 20% gets harder and harder.

[If you're starting out at CrossFit workouts, check out our CrossFit Workouts for Beginners blog here.]

The CrossFit community is a great motivator as well as what you look like in the mirror but if your mind is not in the right place, it can make it 100% more difficult.

Keeping your mind healthy by understanding the reasons behind weight loss can help harbour healthy eating and exercising habits.

If you're not losing weight it could be because of:

  • You're consuming more than you think - are you tracking the oil you use in your pan, the sports drinks you have post workout, the handful of candy or the extra bite of food you steal from your partners plate?

  • You're overestimating the amount of calories you're burning - Online calculators can only be so accurate and smart watches were found to be up to 20% inaccurate on calorie counting so be cautious!

  • Your recovery is compromised - Are you making sure you sleep enough, stretch enough, and are eating the right things? Make sure your recovery is on point.

Drastic weight loss or over exercise can sometimes be unhealthy when done to excess so please seek professional help if required.

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