Heat doesn't just make you uncomfortable.
It actively degrades your performance.
A science-backed guide to fuelling,
cooling and electrolyte strategy for
athletes training and racing
in hot conditions.
Informed Sport certified ·
Built by Alistair Brownlee ·
4.86★ (200+ reviews)
Your Race Fuelling Calculator
Enter your race details and get a personalised gel and electrolyte plan.
Products & Bundles
Start with a bundle or build your own stack. Bundles save you vs buying separately.
CoreCtrl™
4,000mg taurine · 300mg potassium · 60mg magnesium
Energiegele
40g carbs · 0.25/1g salt · hot weather · heavy sweaters
Elektrolyte
400mg sodium · 150mg potassium · 25mg magnesium
Race-Ready-System
40 Energy Gels · 40 Electrolyte Sachets · 8 CoreCtrl Sachets
"Racing Kona in heat is a completely different physiological challenge. Everything about your fuelling and cooling strategy has to adapt."
— Alistair Brownlee, 2x Olympic Champion, truefuels co-founder
Alistair built truefuels because no existing product met the demands of elite triathlon — heat, duration, GI stress all at once. Tested by Alistair and 50+ elite athletes.
Get a free hot-weather fuel plan tailored to your sport and conditions
Personalised gel and electrolyte plan based on your race distance, conditions and target time.
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Frequently Asked Questions
Increases energy cost, accelerates glycogen depletion, amplifies electrolyte loss. ~1–2% drop per °C above 25°C in endurance events.
Add 1 extra electrolyte sachet per hour above cool-condition baseline when training above 25°C.
Reduces core body temperature before exercise. Can reduce core temp rise by up to 0.5°C — a measurable performance benefit. CoreCtrl is built for this protocol.
Yes — higher sweat rate = higher loss per hour. Use high-salt gel variants + higher sachet frequency in heat.
4,000mg L-Taurine · 300mg potassium · 120mg calcium · 60mg magnesium · 250mg Himalayan rock salt. Zero calories, zero carbs. Designed for heat management.
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