What Should a Swimmer Drink at a Meet? Race-Day Hydration, Solved

Swimpros runs Europe's most popular performance swim camp right now, and hydration is the most invisible mistake at swim meets. Nobody sees a swimmer sweat, the pool deck is warm and humid, and by the afternoon session a slightly dehydrated swimmer is flat and slow and nobody knows why.

I am David Karasek, an Olympic finalist and Swiss record holder in the 200m IM. Here is the simple drink plan that covers a whole meet day.

The race-day drink plan

The plan fits in four lines:

• Night before and breakfast: water with the meal, so race day starts topped up, not in a hole. (The full evening plan is in what to eat the night before a swim meet.)
• In the bag: a water bottle plus a bottle of 6% carbohydrate sports drink. Two bottles, that is the whole kit.
• All day: small, steady sips from both. Not big chugs. A stomach full of liquid right before a heat feels exactly as bad as it sounds.
• Nervous swimmer who cannot eat? The 6% sports drink doubles as liquid fuel. This is the same trick we use at breakfast when nerves kill appetite: liquid carbs beat no carbs.

Sip steadily all day. The swimmer who drinks little-and-often beats the swimmer who chugs a bottle when they finally feel thirsty, because thirst shows up late.

Why 6% is the magic number

The research on teenage athletes keeps landing on the same concentration: a sports drink at about 6% carbohydrate (that is 6 g of carbohydrate per 100 ml). At that strength, the drink does three jobs at once over a long meet day:

• Replaces fluid lost to sweat during warm-up, racing and hours on a hot deck. And yes, swimmers sweat; you just never see it.
• Replaces electrolytes, which plain water does not.
• Trickles in carbohydrate between races, supporting the grazing plan from our between-races fuelling guide without sitting heavy in the stomach.

Most mainstream sports drinks sit at about 6%; the label math is simple: carbohydrate grams per serving, divided by serving size in ml, times 100. A 500 ml bottle with 30 g of carbohydrate is exactly 6%.

What not to drink: the 8%+ trap and energy drinks

• Drinks at 8% carbohydrate or higher (many fruit juices, regular sodas, and some sports drinks) tend to cause stomach discomfort in young athletes, exactly what you do not want between heats. If it tastes syrupy, it is probably too strong; dilute it or swap it.
• High-caffeine energy drinks are a no for teenage swimmers. A nervous swimmer behind the blocks already has all the adrenaline they need. Stacking caffeine on top adds heart rate, jitters and stomach upset, and solves nothing that water plus a 6% drink does not solve better. If your swimmer struggles with pre-race nerves, the fix is the mental game, not a can: that is exactly what we coach daily at camp.
• Nothing new on race day. The same rule as food: whatever your swimmer drinks at a meet should already be tested at training.

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