Triathlon Nutrition Calculator

Calculate personalized nutrition and hydration strategy for triathlon training and racing

Triathlon Details

Great for beginners

Affects sweat rate calculations

Use average finish time
Set custom target time

Temperature affects calorie and fluid needs

Race Distances

0.75km
🏊 Swim
20km
🚴 Bike
5km
🏃 Run

Your Nutrition Strategy

928
Total Calories
90g
Carbohydrates
1800ml
Total Fluids
1.5h
Duration

During Race Fueling

🍯 Carbohydrates

Per hour:60g
Every 20 min:23g
Calories per feeding:90 kcal

💧 Hydration

Per hour:1200ml
Every 5-7 min:133ml
Total feedings:4

Pre-Race & Recovery

🌅 Pre-Race (15-30 min before)

Carbohydrates:105g
Calories:420 kcal

🔄 Recovery (within 30 min)

Carbs:84g
Protein:21g
Total calories:420 kcal

Food Options (per 90 kcal feeding)

Energy gel

100 kcal25g carbs

Quick absorption

Banana (medium)

100 kcal25g carbs

Natural sugars + potassium

Dates (5 pieces)

100 kcal27g carbs

Natural whole food

Sports drink (500ml)

120 kcal30g carbs

Hydration + fuel

Race Day Timeline

🏁 Pre-race (15-30 min before):High-carb snack + hydrate
🏊 Swimming:Focus on race start, no eating
🚴 Cycling (after 5-10 min):Start fueling every 20 min
🏃 Running:Continue fueling, prefer gels/liquids
🔄 Post-race (within 30 min):Recovery meal with carbs + protein

Nutrition Tips

Start fueling early - don't wait until you feel hungry

Practice your race nutrition during training

Avoid high-fat and high-fiber foods during race

Drink regularly, don't wait until thirsty

Have a recovery plan ready post-race

Best Race Foods

🏊 Swimming

No eating - focus on technique

🚴 Cycling

Energy bars, bananas, sports drinks

🏃 Running

Gels, dates, diluted sports drinks

Hydration Strategy

💧

Electrolyte drinks for events >1 hour

💧

Take large sips every 5-7 minutes

💧

Switch to water if stomach upset occurs

💧

Monitor urine color for hydration status

Understanding Triathlon Nutrition Science

Energy Systems

Your body stores approximately 2000 calories as glycogen in muscles and liver. For longer triathlons, this isn't enough, requiring external fuel to maintain performance and prevent the dreaded "bonk" or "hitting the wall."

Carbohydrate Requirements

  • <1 hour: No fueling needed, water sufficient
  • 1-2 hours: 30-60g carbs per hour
  • >2 hours: 60-90g carbs per hour

Timing Strategy

Carbohydrates take 30 minutes to be absorbed and available for energy. Start fueling early, even before you feel hungry, to maintain steady energy throughout the race.

Key Calculations

Calories: MET value × weight (kg) × time (hours)

Carbs: 60g per hour for endurance events

Fluids: 500-1000ml per hour depending on conditions

Recovery: 1.2g carbs + 0.3g protein per kg body weight

Discipline-Specific Nutrition

🏊 Swimming Phase

No eating during swim. Focus on pre-race fueling 15-30 minutes before start. Hydration is key, but avoid over-drinking to prevent discomfort.

🚴 Cycling Phase

Most comfortable time to eat. Start fueling 5-10 minutes into bike leg. Solid foods work well here. Aim for 100 kcal every 20-30 minutes.

🏃 Running Phase

Prefer liquid/gel nutrition as chewing becomes difficult. Continue regular fueling schedule. Focus on easily digestible carbohydrates.

Frequently Asked Questions (FAQ)

How much should I eat during a triathlon?

The amount varies based on race duration and intensity. For events under 1 hour, water is sufficient. For 1-2 hour events, aim for 30-60g of carbohydrates per hour. For longer events (2+ hours), target 60-90g of carbs per hour to maintain energy levels and prevent bonking.

Our calculator provides personalized recommendations based on your weight, race distance, and expected finish time to optimize your fueling strategy.

When should I start eating during a triathlon?

Start fueling early in the bike leg, typically 5-10 minutes after beginning the cycling portion. Don't wait until you feel hungry—by then, you're already depleted. Carbohydrates take about 30 minutes to be absorbed and available for energy.

For sprint triathlons, you may only need minimal nutrition during the race if well-fueled beforehand. For Olympic distance and longer, establish a regular fueling schedule every 20-30 minutes.

What are the best foods to eat during a triathlon?

The best race foods are easily digestible and provide quick energy. Options include:

  • During Cycling: Energy bars, bananas, dates, sports drinks, energy gels
  • During Running: Energy gels, liquid nutrition, sports drinks (easier to consume while running)
  • Avoid: High-fat and high-fiber foods during the race as they slow digestion

How much water should I drink during a triathlon?

Hydration needs vary based on weather, intensity, and individual sweat rates. Generally, aim for 500-1000ml per hour, with higher amounts in hot conditions. Take regular sips every 5-7 minutes rather than large amounts infrequently.

For events longer than 1 hour, use electrolyte drinks to replace lost sodium and prevent hyponatremia. Monitor your urine color during training to understand your hydration needs.

What should I eat before a triathlon?

Eat a high-carbohydrate meal 2-3 hours before race start, aiming for familiar foods that you've tested in training. This meal should provide 1-4g of carbs per kg of body weight.

15-30 minutes before the start, consume a small snack (our calculator recommends about 1.5g of carbs per kg body weight) with some water. Good options include a banana, energy gel, or sports drink. Avoid high-fat and high-fiber foods that could cause GI distress.

How do I calculate my triathlon nutrition needs?

Our Triathlon Nutrition Calculator uses several factors to determine your personalized needs:

  • Body weight (affects calorie burn rate)
  • Race distance (determines duration and intensity)
  • Expected finish time (affects total energy needs)
  • Environmental conditions (temperature affects hydration needs)
  • Sex (influences sweat rate calculations)

What should I eat after a triathlon for recovery?

Post-race nutrition is crucial for recovery. Within 30 minutes of finishing, consume a meal or snack containing both carbohydrates and protein. Our calculator recommends 1.2g of carbs and 0.3g of protein per kg of body weight.

Good recovery options include: chocolate milk, protein smoothie with banana, turkey sandwich, or a recovery shake. Continue hydrating and eat a full balanced meal within 2 hours of finishing.

Can I train my gut for race nutrition?

Yes! Gut training is essential for triathlon success. Your digestive system can adapt to process more carbohydrates during exercise. Start by consuming smaller amounts during training and gradually increase over weeks.

Practice your race nutrition strategy during long training sessions. Test different products and timing to find what works best for you. Never try new foods or drinks on race day—use only products you've tested in training.

What's the difference between Sprint and Ironman nutrition?

Nutrition strategies differ significantly based on race distance:

Sprint Triathlon (under 1.5 hours)

Minimal nutrition needed during race. Focus on pre-race fueling.

Olympic Distance (2-3 hours)

30-60g carbs/hour. Begin fueling early in bike leg.

Ironman (8+ hours)

60-90g carbs/hour. Detailed feeding schedule crucial for success.

How do I prevent GI issues during a triathlon?

Gastrointestinal issues are common in triathlons but can be minimized:

  • Train your gut by practicing race nutrition in training
  • Avoid high-fiber and high-fat foods before and during the race
  • Don't over-consume caffeine or try new supplements on race day
  • Pace yourself and avoid going too hard early in the race
  • Stay hydrated but don't overdrink (which can cause stomach sloshing)
  • Use easily digestible simple carbohydrates during the race