Fuel Like a Champion: Nutrition & Hydration Strategy for IRONMAN 70.3 Marbella

Endurance isn’t built only in training — it’s sustained by what you fuel and when you do it.

In Marbella, the sun isn’t just a backdrop — it’s a fourth discipline. With temperatures reaching 25 °C (78 °F) and Mediterranean humidity near 70%, mastering nutrition and hydration is the line between finishing strong and fading on the promenade. Whether you’re a pro, semi-pro, or age-grouper, your strategy must adapt to the micro-climate of the Costa del Sol.

1 · Understand the Heat: Marbella’s Micro-Climate

Protected by the Sierra Blanca mountains and facing the open Mediterranean, Marbella creates a unique mix of radiant sun and ocean breeze. Athletes sweat more but evaporate slower — meaning higher sodium loss and delayed cooling. Adaptation begins in the days before the race, not during it.

• Avg air temp: 19 °C annually, race week 24–26 °C
• Relative humidity: ~70%
• Water temp: 16 °C — wetsuit legal
• Primary threat: heat accumulation during the bike leg

Tip: aim to start the run slightly under-hydrated but well-cooled. Over-drinking in the bike phase increases gut stress and sodium imbalance.

2 · 48 h Pre-Race: Fuel the Machine

Your glycogen tank defines your rhythm. Two days before race day, simplify your plate — minimal fiber, low fat, high carbohydrate density.

• CHO target: 7–8 g/kg/day
• Sodium preload: +1 g/day (table salt or capsules)
• Fluids: 3 L/day (1 L isotonic 4%)
• No: alcohol, fried food, heavy sauces

Breakfast on race morning should follow the 3-3-3 rule: 3 h before start, ~3 g/kg CHO, and 300–400 mg sodium. Example: oats + banana + coffee + isotonic drink.

3 · On-Course Fueling: The Science of Stability

The IRONMAN 70.3 Marbella course alternates climbs, descents, and flat coastal sections. Your fueling plan must synchronize with terrain — not the clock.

4 · Power & Nutrition by Athlete Type

Each profile burns energy differently. Here’s how to align fueling with your target intensity (based on 75 kg athlete, 25 °C conditions):

Masamune Aero Tip: A stable aero position improves digestion efficiency. Less upper-body movement means less gastric stress — another hidden advantage of Masamune design.

5 · The Gut Training Protocol

Your stomach is trainable. In the 4 weeks before race day, simulate race conditions weekly:

• Long ride (3 h) at 70–80% FTP → consume 90 g CHO/h
• Brick session (2 h bike + 40 min run) → practice transitions
• Monitor HR drift & GI comfort

Every successful race is 50% physiology, 50% logistics — train both systems equally.

6 · Heat Management = Performance Management

• Pre-cool: cold towel or ice vest 10 min pre-start
• Bike leg: pour water on arms every 15–20 min
• Run leg: ice under cap + sponge at every aid station
• Post-race: rehydrate with 1.5× fluid loss + 1 g Na⁺/L

Marbella’s Mediterranean heat isn’t the enemy — it’s the test. Adapt, respect, and fuel it right, and it becomes your advantage.

7 · Lead Downloads

8 · Close the Loop

“Fuel early. Drink smart. Run free.”

Marbella rewards those who respect its rhythm. Eat with intent, hydrate with precision, and let endurance flow through every kilometer.

Keep exploring: Race Overview · Bike Strategy · Masamune · Assembly