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Nutrition

Race Nutrition Planner

Create a customized race-day nutrition plan with detailed timing for carbohydrates, electrolytes, fluids, and caffeine based on your race distance and conditions.

How do you plan race nutrition for a triathlon?

A race nutrition plan translates race duration and body weight into a per-hour schedule of carbs (60–120 g/hr), fluid (500–1,000 ml/hr) and sodium (500–1,500 mg/hr). The planner combines gels, drink mix and chews to hit targets without overfilling the stomach. Longer races need higher carb totals and more fluid; pacing and weather shift the number up or down.

Sprint: 20–30 g carbs total (1 gel or none)
Olympic: 30–60 g/hr on the bike and run
70.3: 70–90 g/hr — needs gels plus drink mix
Ironman: 90–120 g/hr — multiple carb sources required

Plan Configuration

Body Weight (kg)

Race Distance

Race Start Time

Expected Finish Time

Race Day Temperature

Example calculation

Athlete: 70 kg triathlete, 70.3 race, 5h 30m, moderate temperature.
Pre-race (3 h out): breakfast ~140 g carbs, 300 mg sodium, 500 ml fluid.
On-course target: 70 g carbs/hr × 5.5 h = ~385 g carbs during the race.
Sodium on course: 800 mg/hr × 5.5 h = 4,400 mg.
Fluid on course: 800 ml/hr × 5.5 h = 4.4 L.

Common mistakes

Waiting until hunger or bonk — by then the stomach has already shut down
Only using one carb source — need glucose + fructose mix to absorb 70+ g/hr
Skipping sodium on a cool day — muscle cramps still hit if sweat rate is high
Not rehearsing the plan in a long training session — race day is the wrong time to find out you can't stomach it

Last updated: April 2026Reviewed by: Bryan Collins, founder

How this calculator works

Carb, sodium and fluid targets per hour are derived from the athlete's body weight, race distance and ambient temperature, then split across pre-race fueling and on-course intervals.

Assumptions

• Carb intake range of 30–120 g/hour scaled by race distance
• Sodium scaled by temperature (cool / moderate / hot)
• Single-loop nutrition plan — multi-loop courses may need re-spacing

Limitations

• Always test fuelling at race pace before race day
• Caffeine timing is generic — adjust to your tolerance
• Does not account for altitude, drafting rules or special-needs bag drops

Who this is for

• Triathletes building a sprint, Olympic, 70.3 or Ironman race-day plan
• Athletes practising fuelling in long training sessions
• First-timers who want a structured starting point

Who this is not for

• Athletes with diabetes — work with a sports dietitian
• Anyone with a clinical GI condition affecting carb absorption