Injured and Not Training? Nobody Tells You to Eat Less. You Just Start Doing It.

It happens somewhere in the first week. Dinner gets a little smaller, because you were not at training. The snack you used to have between school and practice stops happening, because there is no practice. Nobody in your house says a word about it, and you never actually made a decision. By the time anyone notices, your whole day has quietly shrunk around an injury that is still healing.

A 2024 review written specifically about youth and adolescent athletes says it plainly: athletes often mistakenly reduce their energy intake after an injury because their activity dropped. I see it constantly, in high school soccer players and in professionals.

The short version, before the detail. Your energy needs probably do come down a little once training stops, but it's difficult to exactly say by how much. The common mistake is cutting harder and faster than the situation calls for. Protein usually falls as a side effect rather than as a decision. And most of what gets marketed for injury recovery was tested on people who were not injured.

This pattern is noticeable across all sports.

What Is Actually Happening to the Muscle

The biggest fear of anyone with an injury is losing all of their muscle during this time period of decreased activity and training.

In one study, thirteen healthy young men, average age twenty, wore a locked knee brace for a week and got around on crutches. After two days, quadriceps volume in the braced leg was down 1.7 percent. By day seven it was down 6.7 percent. The leg they were still using did not change at all. No athletes in that group, no women, and a brace that did not come off, which is a harder version of sitting out than most injuries involve.

One detail in that study does more work than the headline numbers. The researchers tracked what those men ate across the week in the brace, and their intake did not drop. Energy and protein both held steady. The muscle got smaller anyway.

That is the clearest evidence available on what food can and cannot do here. Prevention was never on the table. What food buys you during a layoff is the repair itself, and something to build back from once the rehab gets real.

A separate study put people in a cast for two weeks and measured two things instead of one. Muscle area dropped about 10 percent. Work capacity in that same leg dropped about 25 percent.

That gap is the useful part. Size and strength do not leave at the same speed, and strength goes first. Which makes the mirror a slow and fairly flattering instrument. You can look close to normal and be nowhere near ready, and if you are judging your progress by what you see, you are using the measurement that lags furthest behind.

Now it's not all doom-and-gloom. Strength is absolutely able to be regained and generally a bit quicker than muscle mass which is the exact rate comparison noted during the loss. Once training resumes the body is incredibly adaptable and is able to build itself back up.

Should You Eat Less While You Are Injured?

When looking at an injury specifically, there really isn't much research looking at the metabolic impact and energy demands for injuries.

You will probably run into a figure claiming injury raises resting metabolism by twenty to fifty percent. That number is real and it comes from trauma and surgery. A sprained ankle is neither of those, and stretching that range to cover one is not honest.

The math genuinely does not resolve either way. Getting around on crutches is hard work minute for minute. Your day also contains a small fraction of the steps it used to. Those two facts pull against each other and nobody has put a number on where they land.

That very situation though paints the picture how even despite a decrease in on field training time, the body is still being put in unique energy demanding situations that can certainly add up. Moments like this on top of just the energy demands of muscle/tendon/bone repair it's important to not overly restrict.

The Protein You Never Decided to Cut

The instinct at this point is to add protein. A shake, a bar, more chicken at dinner. That instinct deserves a fair hearing, because it has actually been tested.

A 2024 review pooled nine articles from eight separate trials, 189 healthy adults, every trial excluding anyone under eighteen. On muscle mass, the pooled result was no effect.

Read what those trials did, though. They took people who were already eating enough and gave them more. That is a fair question and the answer came back no. It is not the question you are living.

What happens at home is different. Portions come down, the afternoon snack disappears, and protein falls as a passenger inside all of that. You never decided to cut it. It went down with everything else, quietly, along with the rest of the day.

So the work is noticing that the day shrank, and holding protein roughly where it was. Spread across meals, rather than piled into dinner because lunch got skipped.

What About Everything on the Supplement Shelf

Short version: most of it measured something other than a healed athlete.

Creatine

Creatine did not protect muscle during casting in the study that tested it. It looked more useful once training restarted, which is a different phase from the one you are in while you are still sitting out. While creatine may not directly help speed up the recovery process, it can maintain the creatine levels in your body to hit the ground running once better and also to still get the cognitive/mental benefits from it.

Omega-3

Omega-3 reduced muscle loss in twenty healthy young women, who had been taking it for four weeks before the immobilization even started. That is not a plan available to anyone whose injury was a surprise. What it can do is help reduce inflammation though. This certainly is a helpful piece of the puzzle though overall which we'll dive into.

Collagen and gelatin

The gelatin (the main thing is Jello) and vitamin C study that gets quoted everywhere measured a collagen marker in blood and a lab-grown ligament. It did not measure a healed tendon in a person. Most collagen research showing tendon change also involved weeks of loading, and during complete time off there is no loading to pair it with.

Anti-inflammatory supplements

There is one thing I do differently here, and it goes against the instinct.

For roughly the first week, I hold off on adding anti-inflammatory supplements. The swelling and the soreness feel like the problem to solve. They are closer to the instruction. Inflammation is the signal that tells your body repair work needs doing, and blunting that signal early with a high dose can work against the thing you are trying to speed up.

Two things I want to be precise about, because this gets misread.

I am talking about supplements and the doses they deliver, not food. Berries, fatty fish, olive oil, turmeric in your cooking, all of that stays exactly where it is. Food is not where excessive dosing happens.

And if a doctor has prescribed or recommended something, you take it. That is a medical decision and it is not mine to override. I work around what your medical team has decided.

To be straight about where this sits: the general principle that inflammation does useful work is well supported, and the 2026 International Society of Sports Nutrition position stand favors getting antioxidants from food rather than high-dose supplements.

One more thing worth knowing about what determines how long you are out. In a study of collegiate track and cross country athletes with bone stress injuries, the factors that independently predicted return time were injury grade and bone density. No supplement appeared anywhere in that model.

The Part That Is Harder to Say Out Loud

For a lot of athletes, the difficult part of eating during an injury has very little to do with knowing what to eat.

In interviews with twenty-eight national-level athletes, eighteen described anxiety about gaining weight while they were injured. That group was already being assessed for eating disorder symptoms, so the proportion is not a rate for injured athletes generally. What it does tell you is that the fear is real, specific, and turns up in serious athletes.

There is also survey work in 846 competitive female athletes where restrictive eating and a history of disordered eating were each associated with reported injury. That study is cross-sectional, so it cannot tell you which came first, and reading it as proof that restricting causes injuries would be going well past what it shows. It is a reason to take the pattern seriously rather than a reason to panic about it.

If your first thought after getting hurt was about your body, that is a normal thought and it is worth saying out loud instead of carrying quietly.

So I ask a different question. What are you working to achieve, and are you fueling in a way that gets you there? Body image and body composition concerns are certainly valid and real feelings, but it's important to remember the priority in this moment. That priority is getting back on the field.

Some change across a layoff though is expected. It is not a failure, and cutting hard to prevent it takes energy away from the repair that is the whole point of the six weeks.

What Pro Soccer Players Get That You Probably Do Not

The gap between a professional environment and a high school one during an injury is not the facility, and it is not some supplement nobody else can buy.

It is that somebody is in the room.

When a soccer player goes down at that level, an athletic trainer or a sports dietitian is with them that same day, saying it takes energy to recover and heal. Then saying it again three days later. Then again the week after. I have watched that up close for a long time and the repetition is the entire intervention. It stops the wrong idea before it ever takes hold, because someone keeps getting in front of it.

You go home, training stops, the routine disappears, and nobody is having that conversation with you at all.

That gap does not close by buying anything.

What I Actually Do With Injured Athletes

Four things, in this order.

Find out what your medical team has already said. Whatever the doctor, the athletic trainer or the physical therapist has decided comes first, and everything on the nutrition side works around it rather than over the top of it.

Hold the anti-inflammatory supplements in the short term. Food nor prescribed medication is not included in that. Those things absolutely should continue to be had.

Keep the restriction from getting extreme. Healing is work and the energy for it has to come from somewhere. A gradual adjustment while you watch how you feel beats cutting hard on day one.

Hold protein steady across the day. Not stacked into dinner. Spread across the meals you are still eating and ensuring you hit your total daily needs.

Then pick one of those and start there. You are already doing the hard part by showing up to rehab and being patient with a timeline you did not choose. The food does not have to be perfect but we need to make sure that it doesn't quietly shrink.

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Frequently Asked Questions

Should I eat less while I am injured?

Likely a little, but nobody has directly measured how much. There is no published study tracking energy needs across an ordinary sports injury layoff. The common mistake is cutting far harder than the situation calls for, usually within the first week and usually unintentionally.

How fast will I lose muscle if I am out for six weeks?

Faster than most people expect at the start, and unevenly. Strict immobilization studies show measurable change within two days, with quadriceps volume down 6.7 percent by day seven. Strength falls faster than size, so looking normal is not the same as being ready. Rates vary a lot depending on the injury, whether you can bear weight, and what rehab you are doing. It does come back though!

Can I stop the muscle loss by eating more?

No, and the clearest evidence on that comes from a study where participants held both their energy and their protein intake steady across a week of knee immobilization and lost 6.7 percent of quadriceps volume anyway. Food during a layoff funds the repair and gives you something to rebuild from. Completely preventing the loss is not one of the things it does.

Should I take collagen or a protein shake while I am injured?

The trials that tested adding protein during immobilization found no effect on muscle mass, and they were run in adults who were already eating adequately. The collagen research most people cite measured a marker in blood rather than a healed tendon. Getting enough protein from food, spread across the day, is the more useful target.

Do anti-inflammatory supplements slow down healing?

Inflammation is the signal that starts the repair process, so blunting it early with a high-dose supplement could work against recovery even when the intention is good. In practice I hold off on adding them for roughly the first week. This applies to supplements rather than to anti-inflammatory foods, and never to medication a doctor has prescribed.

Can a sports dietitian actually help while I am injured and not training?

Yes, and it is one of the more useful windows for it. Most of what goes wrong during a layoff happens in the first week, quietly, before anyone is paying attention to food at all. Working out what changes and what stays the same takes one conversation, not a program.

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If you are sitting out right now and the conversation at your house has turned into how much less you should be eating, that is exactly what the free 15-minute Discovery Call is for. We will discuss the mentality shift and how proper nutrition can help. Book Your Discovery Call

Jay Short, MS, RD, CSSD is a Registered Dietitian and Board Certified Specialist in Sports Dietetics, and co-owner of Rise Nutrition, specializing in sports dietetics for competitive athletes. He works with US Soccer (all 27 teams), the Columbus Blue Jackets (NHL), and athletes across MLS, collegiate, and club programs.

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References

1. Alcock R, Hislop M, Vidgen HA, Desbrow B. Youth and Adolescent Athlete Musculoskeletal Health: Dietary and Nutritional Strategies to Optimise Injury Prevention and Support Recovery. https://pubmed.ncbi.nlm.nih.gov/39584874/
2. Kilroe SP, Fulford J, Holwerda AM, Jackman SR, Lee BP, Gijsen AP, van Loon LJC, Wall BT. Short-term muscle disuse induces a rapid and sustained decline in daily myofibrillar protein synthesis rates. https://pubmed.ncbi.nlm.nih.gov/31743039/
3. Hespel P, Op't Eijnde B, Van Leemputte M, Ursø B, Greenhaff PL, Labarque V, Dymarkowski S, Van Hecke P, Richter EA. Oral creatine supplementation facilitates the rehabilitation of disuse atrophy and alters the expression of muscle myogenic factors in humans. https://pubmed.ncbi.nlm.nih.gov/11600695/
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8. Nattiv A, Kennedy G, Barrack MT, Abdelkerim A, Goolsby MA, Arends JC, Seeger LL. Correlation of MRI grading of bone stress injuries with clinical risk factors and return to play: a 5-year prospective study in collegiate track and field athletes. https://pubmed.ncbi.nlm.nih.gov/23825184/
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