What's the best way to fuel *before* a chilly open water swim to avoid bonking?

For those colder open water swims, it's crucial to give your body sustained energy without feeling heavy. About 1-2 hours before your swim, aim for a meal that combines complex carbohydrates with a little protein and healthy fat. Think oatmeal with nuts and berries, or whole-wheat toast with avocado and eggs. For a quick, easily digestible boost closer to your swim, consider a Hammer Gel or a few bites of a Clif Bar. This approach ensures you have the energy reserves needed and addresses how to fuel for swimming effectively from the start.

I get dehydrated easily during long open water swims, especially in choppy conditions. What are your top hydration tips?

Staying hydrated is key in open water, and it’s trickier than in a pool. Start hydrating well in advance of your swim, not just 30 minutes before. Sip on water throughout the day, and consider an electrolyte drink like our HEED if your swim is over an hour or in very hot conditions. For longer efforts, a concentrated electrolyte formula mixed with water can be your best friend. Regularly sipping from a soft flask or hydration pack (if possible) is much more effective than trying to gulp large amounts at once.

How do I keep my energy levels up during a long open water race or training session? Carrying gels is tricky!

Sustaining energy during long open water efforts is critical. For swims over 90 minutes, you'll want to take in calories every 30-45 minutes. Our Hammer Gels are designed for easy digestion and quick energy. We also offer Endurolytes in capsule or powder form, which are vital for replacing electrolytes lost through sweat. If you can manage it, strapping a couple of gels to your goggles or suit or using a small, streamlined hydration system can make a big difference. This is the core of how to fuel for swimming during intense efforts.

What should I eat and drink immediately *after* a tough open water swim for the best recovery?

Post-swim recovery is vital for muscle repair and preparing for your next session. Within 30-60 minutes of finishing your swim, aim to replenish your energy stores and rehydrate. A recovery drink containing a 3:1 or 4:1 carbohydrate-to-protein ratio is ideal. Our Hammer Recoverite is specifically formulated for this. Alternatively, a banana with a handful of almonds or a chocolate milk can also work. Don't forget to continue sipping water or an electrolyte drink to fully rehydrate.

Collection: HOW TO FUEL FOR SWIMMING

Swimming nutrition for training, open water events, pool racing and triathlon swim legs — sustained energy, hydration and recovery without digestive issues. Hammer’s clean, proven endurance formulas trusted by swimmers to maintain performance from the first stroke to the finish.

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Fuel by Swim Type

Pool training Under 90 mins	Endurolytes Fizz in your water bottle poolside. Hydration and electrolyte replacement without calories. No fuelling needed for most sessions under 90 minutes.
Long pool sessions 90 mins+	Hammer Gel at the wall between sets + Endurolytes Fizz for hydration. 1 gel per hour of sustained effort. Easy to consume quickly without disrupting your session.
Open water swimming 1–3 hours	Hammer Gel (pre-swim + at feed stations) + HEED Sports Drink at feed points. Endurolytes capsules pre-swim and at feeds. Practise your feed strategy in training.
Long-distance open water 3+ hours	Perpetuem or Perpetuem Solids at feed stations + Hammer Gel + Endurolytes Extreme. Sustained carbs + protein for multi-hour efforts.
Triathlon swim leg	Hammer Gel 10–15 mins before the start. Minimal in-swim fuelling — focus on arriving at T1 with energy reserves intact. Begin fuelling on the bike within the first 15–20 mins. Full triathlon guide →
Post-swim recovery	Recoverite® within 30–60 mins. 3:1 carb:protein + 3,000mg L-glutamine + electrolytes. Replenishes glycogen and begins muscle repair after demanding sessions.

Swimming Nutrition Notes

Swimmers still lose electrolytes — water immersion masks sweat, but mineral losses still occur during prolonged swimming and affect performance
Avoid heavy meals before swimming — a light carbohydrate snack 60–90 mins before is preferable to a full meal to avoid digestive discomfort
Hammer Gel is easy to take at the wall — fast to consume, no chewing, no mess, fits in a swim cap or tow float pocket
Practise your open water feed strategy — never try a new product or timing approach on race day