Nutrition & Hydration for Mountain Athletes 101

August 21, 2025

Fuel Your Performance

Strategic Nutrition & Hydration for Mountain Athletes

At Alpine Performance Labs, we don’t guess on fueling. We calculate, test, and coach it like any other performance variable. What you eat and drink—and when—can mean the difference between consistent output, consistent volume and chronic fatigue.

Use this framework to optimize how you fuel before, during, and after training—especially in high-load environments (heat, altitude, back-to-back days).

Pre-Training Nutrition (4h–0h)

Eat Low Fat, Low Fiber → Fast Delivery, Fast Absorption

Timing	Carb Target	Protein Target	Hydration	Simple Rules
3–4h prior	~1.5g/kg BW	~0.4g/kg BW	14–20oz + electrolytes	4:1 Ratio, 80-120g Carb, 20-40g Protein
1–2h prior	~1.0g/kg BW	~0.25g/kg BW	8–14oz	4:1 Ratio, 80g Carb, 20g Protein
15–30 min	~0.3g/kg BW		4–8oz,	A gel (20-30g Carb) or light sweet snack.

Pro Tips:

Think: bagel, eggs, fruit, juice (3–4h out) → light snack (closer to session)
Hydration starts early. Add electrolytes to pre-load if heat/altitude is involved.

During Training – Especially On Hill / Long Efforts

Fluids + Carbs + Sodium = Sustained Output

Training <1 hr: water only, however, electrolyte and carbohydrate are encouraged.
Training >1 hr or at high intensity:
- 30–90g carbs/hr (gels, sports drink)
  - Recommendations are highly specific to the training session, experience, athlete and time of year.
  - Higher carbohydrate intakes are possible and valuable, however, should be carefully managed. Graded exposure is recommended to offset the likelihood of GI disaster 🙂

Electrolytes for heat/humidity

■ These are highly specific, however, general recommendations are below.

250-750 mg Sodium / Hr is a good bench mark
500+ mL Fluid (water) is also a good bench mark.
- Most athletes will need more (1.5-3x) than this, especially during long duration, at altitude and in summer temperatures.

Pro Tip: Start low, scale up. Train the gut like any other system. Cramping or fade-outs often trace back to under-fueling, not lack of grit.

Consider this: your fueling, hydration and electrolyte demands are an orchestrated symphony, each component play a different role. As much as possible, develop a system that:

Works well for you, time and time again.
Can be modular. Having a single solution in a bottle is great, until you need just water, or just carbohydrate. And sometimes, you just need a little more cow bell.

Post-Training Recovery (0–2h)

Rebuild, Rehydrate, Restore

Focus	Carb (g/kg)	Protein (g/kg)	Fluids
Strength Day	0.55	0.55	150% of fluid lost
Endurance	1.65	0.5	150% of fluid lost
Mixed Day	1.1	0.5	150% of fluid lost

What this looks like:

More protein than you think 🙂
Protein sandwich + fruit + shake
7–8oz lean protein + potatoes or pasta + vegetables
Add 16–24oz of fluids for every pound lost in sweat (weigh in/out)

Why It Works: Replenishing carbs restores glycogen. Protein supports repair. Hydration ensures delivery of both. Further more, delays in any of these reduce next-day capacity—even if biomarkers look “normal.”