The Calorie Math
A full day on El Capitan burns somewhere between 4,000 and 6,000 calories depending on difficulty, temperature, and how much hauling you are doing. That is roughly double what most people eat in a normal day, and you have to consume most of it while hanging from a wall.
Early in my climbing career, I made the classic mistake: I underfueled. I would bring a couple bars and some trail mix and wonder why I felt destroyed by pitch 15. The math simply did not add up.
My Big Wall Nutrition System
After years of trial and error (and a degree in sports nutrition), I have developed a system that works reliably:
The Night Before
- Large dinner with complex carbs, moderate protein, healthy fats
- Something like rice bowls with salmon, avocado, and roasted vegetables
- Hydrate well but stop fluids 2 hours before bed to avoid midnight bathroom trips
Morning of the Climb
- Wake up 2 hours before the approach starts
- Oatmeal with banana, nut butter, and honey — roughly 600 calories
- 16oz water with electrolytes
- Small coffee — enough for alertness, not enough for anxiety
On the Wall
- Every 2 hours: 200-300 calorie snack (dates, nut butter packets, rice cakes)
- Every pitch: 4-6 sips of water with electrolyte mix
- Lunch at a good ledge: Tortilla wraps with cheese and jerky, dried fruit
- Emergency stash: Gel packets for when energy crashes unexpectedly
Hydration Is Half the Battle
Dehydration impairs grip strength before you feel thirsty. On hot days in Yosemite, I plan for 500ml per hour minimum. That is a lot of water to carry, but the alternative — bonking on pitch 20 with 12 pitches to go — is not an option.
The wall does not care if you forgot to eat. It will collect on that debt with interest.
What I Have Learned
The biggest lesson: eat before you are hungry, drink before you are thirsty. By the time your body sends those signals on a big wall, you are already behind. Consistent small inputs beat reactive large meals every time.
And honestly, food tastes better 2,000 feet up. That is just science.
