Training for months and failing… in nutrition.
In a trail race, especially over long distances, nutrition stops being a detail and becomes a strategy.
Trail running is not the same as road running.
What changes?
-
Intensity variability
Long climbs increase glycogen consumption.
Technical descents increase muscle stress.
The energetic cost per hour tends to be higher. -
Longer duration = higher gastrointestinal risk
As hours pass, the risk of:
- hypoglycemia
- dehydration
- hyponatremia
- nausea
- central fatigue
During prolonged exertion, blood flow to the gastrointestinal tract decreases.
If the gut has not been trained, problems arise.
-
Unpredictable conditions
Heat, cold, altitude, and humidity alter:
- hydration needs
- carbohydrate absorption
- sensation of hunger and thirst
Practical strategy by duration
Up to 2h30
30-60g of carbohydrates per hour
Simple solutions like gels and isotonic drinks
3-6h
60-75g CH/h
Glucose + fructose combination
Introduction of easy-to-chew solids
Sodium control 500-700mg/h depending on sweating
Ultra trail | +6h
75-90g CH/h in trained athletes
Alternating sweet and savory
Gastric volume control
Strategic caffeine management
Nutrition is not just about ingesting energy.
It's about reducing metabolic stress and preserving months of training.
