Gymnast Weight Gain: What’s Normal and When to Worry

Gymnast weight gain is one of the most stressful things a parent (and a gymnast) can face. Maybe she stepped on the scale after a few weeks off, or a coach made a comment, or she’s suddenly worried her leo fits differently. Here’s the thing: for a growing gymnast, weight gain is usually normal, often necessary, and almost never a reason to diet.

Let’s talk about why the number on the scale changes, what’s normal during growth and puberty, what to do after an injury or a break, and when it actually makes sense to look closer.

By Christina Anderson MS, RDN, CSP, CSSD · Updated October 2026

Is weight gain normal for a gymnast?

Yes. Under 18, it is NORMAL to keep growing, developing and gaining weight, and for some girls this continues into the early twenties. It would be abnormal for a gymnast to weigh the same at 18 as she did at 12.

On average, girls ages 9-12 gain about 5-7 pounds a year, and from 13-17 many gain 15-30+ pounds as part of puberty. That’s not “getting bigger.” That’s growing up.

For a lot of gymnasts, this timeline is delayed by underfueling. When a gymnast doesn’t eat enough to match her training, growth and puberty slow down. I see 14-16 year old gymnasts who still look 10-12. That’s NOT a good thing. It comes with stress fractures, injuries and stalled progress. (More in Does Gymnastics Stunt Your Growth? and Does Gymnastics Delay Puberty?)

So when a gymnast who’s been underfueled finally starts eating enough, some weight gain is often her body catching up. That’s a sign of health, not a problem.

Why the scale isn’t telling you the whole story

A parent once emailed me, worried because her 15-year-old gymnast stepped on the scale for the first time in a month or two and was up 3-5 pounds. They were both worried about muscle loss and fat gain.

Here’s what I told them: the scale can swing 2-5 pounds in a single day. It’s impossible to know if that number was “real” weight gain or not. She’s still growing, so I’d want to see her growth charts first, because this could easily be normal growth. Her menstrual cycle, hydration and what she ate the day before all shift the number too.

A few things the scale can’t tell you:

• Fluid shifts. A salty dinner the night before can show up as “weight gain” the next morning. It’s water, and the body balances it out on its own.
• Her cycle. Weight naturally goes up and down across the month.
• Muscle vs. fat vs. bone. Two gymnasts can weigh the exact same and look completely different. For an athlete, what her body can DO matters far more than what it weighs.
• Growth. A growing kid’s weight is supposed to go up.

This is why I’d rather look at a weight range and her growth curve over time than a single number. (More in How Much Should a Gymnast Weigh?)

Performance over appearance

Gymnastics is an aesthetic sport, and social media has made it worse. Our young athletes see “fitfluencers” with shredded abs and have NO idea how much restricting and overexercising it takes to look that way.

Physique competitors often get down to body fat levels so low they lose their periods, feel cold all the time, can’t sleep or recover, and lose strength. Many end up regaining more than they lost once the show is over, because the body fights back against starvation. That’s not a look a growing gymnast should chase.

For an athlete, we’re going for performance, not a look. If she’s performing well, recovering well and healthy, the number on the scale matters a lot less than people think. (See Is There a Gymnast Body Type?)

What about weight gain after an injury or time off?

Weight gain during an injury or a break from training is common, and it’s usually OK.

For many young gymnasts, it’s a normal part of growth and development that was going to happen anyway. Time off can also let a body that’s been underfueled for years finally catch up.

Some gymnasts will gain a little body fat when training drops from 20-30 hours a week to just a few. That’s understandable. Most of it comes back off naturally once she’s back to full training and fueling well.

What makes the biggest difference is something called periodized nutrition: eating more when training is heavy and scaling back a bit when it’s light. Most gyms train hard year-round, so gymnasts rarely learn this. When a gymnast is fueling well to begin with, we see much less unwanted weight change during time off. (More in Gymnast’s Guide to Injury Time Off.)

Sometimes weight gain is exactly what she needs

If your gymnast got her period back during a break, or started growing again, that’s a GOOD sign. It usually means she wasn’t fueling enough when training was at full volume. Missing periods are not normal for an athlete, and birth control doesn’t fix the underlying problem. (See Do Gymnasts Get Periods?)

I also see many gymnasts reach college still very pre-pubertal, then gain a lot of weight between senior year and freshman year as training drops and they’re on their own with food. In my opinion, it’s better to develop BEFORE college gymnastics, so that’s one less big change to deal with at once.

If your gymnast is underweight or not growing and needs to gain, see our guide to helping an underweight gymnast gain weight.

What should we do if she has gained weight?

Don’t diet. Crash dieting to lose a few pounds leads to dehydration, disordered eating and poor performance. Many gymnastics careers have been derailed by “just trying to lose 5 pounds” that spiraled into an eating disorder, injuries, anxiety and quitting the sport she loved.

Instead:

• Fuel for the work required. Regular meals and snacks, with fuel before, during and after practice. (See What to Eat Before Gymnastics Practice.)
• Look at her growth charts with her pediatrician, not just the scale.
• Focus on performance: energy, strength, recovery and progress in the gym.
• Get help if eating feels out of control. Weight gain from emotional eating or binge-restrict cycles needs support from a registered dietitian and often a therapist. Restricting often leads to bingeing, eating in secret, and a lot of guilt and shame.

A note for coaches

Telling a gymnast she’s “fat” or has “gained weight” is never helpful. I have so many stories of gymnasts singled out at practice with no referral to a professional who could actually help. Usually she starts starving herself, because that’s the only way she knows to “lose weight,” and it’s a slippery slope into an eating disorder. And who’s to say she actually needs to change anything? If you have a concern, bring it to the parents and refer to a sports dietitian. (More in Should Gymnasts Lose Weight?)

Frequently asked questions

Get help for your gymnast

One number on the scale can’t tell you if she’s actually “gained weight” or is just seeing normal fluid shifts and growth. For a young athlete, weight gain is a normal and expected part of healthy development.

Not sure if your gymnast is fueling enough for her growth and training? Take our free Underfueled Gymnast Check. And if you want more than a generic meal plan, The Balanced Gymnast® Program is our 1:1 program, built by a former gymnast, nationally rated NCAA/USAG judge and pediatric sports dietitian who lives and breathes this sport. We build her plan around HER: her growth, her training, her relationship with food and her body, and the foods she actually likes.