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SwimmingWhat to eat before and after swim practice
In one elite college group, early sessions were where the gap was. · 3 min read · Updated October 1, 2026
How we made this guide: we built it from the research below and checked every number against it: Shaw et al., Nutrition for Swimming (2014); Lundstrom et al., collegiate swimmers’ intake (2025); Klein et al., Division III swimmers (2023); Thackray et al., swimming and appetite (2020); Grigg et al., water-based exercise and appetite meta-analysis (2023); Maughan et al., swimmers’ sweat and fluid (2009).
Swim practice tends to start early, last long and leave you starving. The research below covers the first and the last.
The guidance
The expert review “Nutrition for Swimming” (Shaw et al., 2014) recommends 3–10 g of carbohydrate per kg of body weight a day, scaled to how much and how hard you train, and about 0.3 g/kg of protein right after key sessions and spread through the day.
| Body weight | Protein after a key session (0.3 g/kg) |
|---|---|
| 110 lb (50 kg) | ~15 g |
| 130 lb (59 kg) | ~20 g |
| 150 lb (68 kg) | ~20 g |
| 170 lb (77 kg) | ~25 g |
| 190 lb (86 kg) | ~25 g |
Calculated from 0.3 g/kg and rounded to the nearest 5 g.
Where these swimmers fell short: the first session
Lundstrom and colleagues (2025) tracked 25 elite NCAA Division I swimmers during heavy training. None met carbohydrate recommendations before or during the first session of the day, and only 7 of 25 met their daily carbohydrate target. Protein was almost never the problem: 24 of 25 met it. The authors suggest early starts, low morning appetite and stomach discomfort may explain it.
A study of Division III swimmers before their season (Klein et al., 2023) found 43% of 30 swimmers had low energy availability on 3-day food records, meaning they weren’t eating enough to cover training and normal body function.
If you can’t eat much at 5 a.m.
These are practical ideas of ours, not findings from the studies above.
- Something small beats nothing. A banana, toast with honey, or a glass of juice is easy on a sleepy stomach.
- Drink some of it. Juice or a milky drink is easier than a full breakfast for many people.
- Make up for it after. Have carbs and protein soon after practice, especially if there’s a second session later.
Yes, people eat more after swimming
In a lab study of 32 young adults (Thackray et al., 2020), an hour of hard swimming led people to eat about 600 kJ (roughly 140 kcal) more at a buffet afterwards than on a rest day. A meta-analysis of water-based exercise (Grigg et al., 2023) found a smaller average increase, about 330 kJ, and no difference from similar exercise on land. These were single meals, mostly in non-athletes, so treat the numbers as a sign, not a rule: eating more after a swim showed up in these studies, and planning a snack is easier than fighting it.
Do you need to drink during practice?
You do sweat in the pool, though the amounts measured were modest. On average, national-level swimmers in a hot indoor pool lost about 0.31 L of sweat an hour and stayed hydrated while drinking as they normally would (Maughan et al., 2009; 17 swimmers, two sessions). Individuals vary, so keep a bottle on the deck and drink as you normally would.
Log the early sessions
The gap in these studies is the first session of the day, and it’s easy to miss without a record. We built My Track Record so logging that 5 a.m. banana and the practice after it is one spoken sentence.
General information for healthy adult and college-age swimmers, not medical advice. Younger swimmers have extra needs while growing; if you have a medical condition, have missed periods, or have a history of disordered eating, talk to a doctor or registered dietitian.
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By Andrew, founder of My Track Record. Andrew has been active all of his life across a variety of sports and continues to stay active through climbing, swimming, weight training, golfing, snowboarding, and more. He built My Track Record so logging food and training takes one spoken sentence and can support any activity. He puts these guides together from published sports science research cited on each page. About AndrewSources
- Shaw G, Boyd KT, Burke LM, Koivisto A. Nutrition for swimming. Int J Sport Nutr Exerc Metab. 2014;24(4):360–372. Source
- Lundstrom EA, et al. Elite collegiate swimmers do not meet sport nutrition recommendations during heavy training: effects of sex and within-day nutrient timing. J Int Soc Sports Nutr. 2025;22(1):2494846. Source
- Klein DJ, et al. Pre-season nutritional intake and prevalence of low energy availability in NCAA Division III collegiate swimmers. Nutrients. 2023;15(13):2827. Source
- Thackray AE, et al. An acute bout of swimming increases post-exercise energy intake in young healthy men and women. Appetite. 2020;154:104785. Source
- Grigg MJ, et al. Influence of water-based exercise on energy intake, appetite, and appetite-related hormones in adults: a systematic review and meta-analysis. Appetite. 2023;180:106375. Source
- Maughan RJ, et al. Water and salt balance of well-trained swimmers in training. Int J Sport Nutr Exerc Metab. 2009;19(6):598–606. Source