Mountain Running Training Principles
How to train for a mountain ultramarathon. The few things that actually matter: run easy, get strong, build slowly, and train on mountains.
The Whole Thing in Four Sentences
Run easy almost all of the time. Get strong in the gym. Build up slowly over months. As race day gets closer, run on terrain that looks like your course.
That’s really it. Everything below is just explaining why.
Run Easy (No, Easier Than That)
In a 100-mile mountain race, you spend virtually the entire day below your aerobic threshold. Zone 2 isn’t “base training”—it’s your race pace.
So 80-90% of your training should be at a pace where you can hold a real conversation. Not a few words between breaths. A conversation. If someone called you mid-run and couldn’t tell you were running, you’re in the right zone.
This is hard to accept because it feels too slow. You’ll wonder if you’re even getting fitter. You are. Your body is building the infrastructure that powers long efforts—more mitochondria, denser capillary networks, better fat burning. You just can’t feel it happening.
The mistake most people make is training in the middle: not easy enough to recover from, not hard enough to produce top-end gains. If your easy days are moderately hard and your hard days are moderately hard, everything is moderately hard and nothing is working.
| Intensity | How Much | How It Feels |
|---|---|---|
| Zone 1-2 | 80-90% | Conversational. Could do it all day. |
| Zone 3 | 5-10% | Focused. Sentences get shorter. |
| Zone 4-5 | 0-10% | Hard. Minutes, not hours. |
Get Strong
Mountain ultras destroy runners who only run. Steep descents hammer your quads eccentrically. Rocky terrain demands ankle stability you can’t get from road miles. Long climbs require hip strength that running doesn’t build.
The fix is simple:
- Single-leg exercises: Lunges, step-ups, single-leg deadlifts. Running is a single-leg sport.
- Hip work: Lateral band walks, clamshells. Weak hips cause most running injuries.
- Core: Planks, dead bugs, anti-rotation presses.
- Eccentric loading: Slow-descent squats, Nordic curls. This is your downhill insurance.
Do 2-3 gym sessions per week during base building, scale back to 1-2 as your running volume peaks. It doesn’t need to be complicated. It just needs to happen.
Build Slowly
Your body adapts on its own schedule, not yours. Increase weekly volume by 5-10%. Take a recovery week every 3-4 weeks where you drop volume by about 30%. Build your hours before you build your intensity.
That’s the whole rule. People get injured because they ignore it.
Train on Mountains
Early in a training cycle, general fitness is fine—road runs, flat trails, treadmill. As race day approaches, your training needs to look more like your race.
If your race has 23,000 feet of climbing, you need to train on steep climbs. If the course is rocky single track, run on rocky single track. If you’ll be out for 24+ hours, your body needs to know what 4+ hours on its feet feels like. Practice your nutrition during long efforts. Run in your race gear.
Nothing new on race day. Ever.
Periodize
Training moves through phases. Each one has a job.
| Phase | Duration | What You’re Doing |
|---|---|---|
| Base | 8-16 weeks | Easy miles, gym strength, building volume |
| Build | 6-10 weeks | Longer long runs, back-to-backs, tempo climbs |
| Peak | 3-6 weeks | Race simulations, max volume, sharpening |
| Taper | 1-3 weeks | Cut volume, keep some intensity, rest up |
Base building is the most important phase and the one most people cut short. Resist the urge to skip ahead.
Listen to Your Body
Plans are guidelines. Your body is the real coach.
Track your morning resting heart rate. If it’s 5+ beats above your normal baseline, you’re accumulating fatigue faster than you’re recovering. Back off.
Pay attention to how easy feels. If your easy runs feel hard, something is wrong—usually insufficient sleep, too much life stress, or too much training volume.
Rest now or rest later. You can take two easy days when your body asks for them, or you can take six weeks off with an injury. Your choice.
Where to Start
- Find your zones. Do a heart rate drift test to find your actual aerobic threshold. Train by your numbers, not a formula.
- Check your aerobic base. If the gap between your aerobic and anaerobic thresholds is bigger than 10%, focus on easy running until it closes.
- Start where you are. Build from your current fitness, not where you were six months ago.
- Be patient. Aerobic development takes months. There are no shortcuts that don’t eventually cost you time.
Related Pages
- Heart Rate Zone Testing for Mountain Runners
- Sleep Optimization for Ultramarathon Training
- Crazy Mountain 100: 20-Week Training Plan
Recommended Reading
- Training for the Uphill Athlete by Steve House, Scott Johnston, and Kilian Jornet
- Training for the New Alpinism by Steve House and Scott Johnston
- 80/20 Running by Matt Fitzgerald
Adjust everything based on how your body responds. When in doubt, sleep more and run easier.
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