Trail running asks more of your legs than road running: steep climbs, long descents, uneven ground, hours on tired muscles. Strength training is how you prepare them for that. Not bodybuilding, and not hours in the gym: two short sessions a week, built around a handful of exercises, changing through the season. This guide covers why it works, which exercises matter most, and how to fit it around your running.
In short. Two sessions a week of 30 to 45 minutes in the base phase, one or two in build, one short maintenance session in peak, none in the last week before a race. Mostly single-leg work, heavy enough that the last reps are hard, plus calves, hips and slow descents. Do it on hard days, after the run, not the day before a key session.
Why strength helps runners
- Running economy. Reviews of the research find that adding heavy strength training to endurance training improves running economy: you use less energy at the same pace. Stiffer, stronger tendons and muscles return more energy with each stride.
- Descending. Downhill running makes your quadriceps work while lengthening (eccentric work), which causes most of the muscle damage in a mountain race. Muscles trained eccentrically are damaged much less by it, which is often the difference between running the last descent and walking it.
- Fewer injuries. A large analysis of injury-prevention studies found strength training cut sports injuries to less than a third, a bigger effect than stretching or most other measures.
- Climbing and hiking. Strong glutes, quads and calves make steep hiking cheaper, and on most mountain ultras a lot of the race is hiking.
The worry that strength training makes runners heavy or slow doesn't hold up for runners doing a couple of sessions a week alongside a full running load. You get stronger mostly by your nervous system using the muscle better, not by adding much muscle.
The exercises that matter most
You don't need a long list. A trail runner's strength training covers a few movement patterns, mostly on one leg, because running is a series of single-leg landings.
| Pattern | Exercises | Why |
|---|---|---|
| Single-leg squat | Bulgarian split squat, step-up onto a high box | Climbing power, knee control, balance between legs. |
| Slow descent | Step-down from a box (3 to 4 seconds down), slow lunges | Eccentric quad strength for descending. |
| Hip hinge | Romanian deadlift, single-leg Romanian deadlift | Hamstrings and glutes, a strong back for long days with a pack. |
| Calves | Heel raises with straight knee and with bent knee (soleus) | The calves take the biggest load per stride, especially uphill. |
| Hips | Hip thrust, side plank with leg lift, banded side steps | Pelvis control on uneven ground, fewer knee and IT-band problems. |
| Trunk | Dead bug, side plank, carries | Holding posture late in a race, carrying a pack. |
| Springiness | Pogo jumps, skipping, bounding uphill | Tendon stiffness and quick ground contact (add once you have a base). |
How heavy, how many
For running economy, the research favours heavy strength work: weights you can lift only 4 to 8 times with good form, for 3 or 4 sets, with 2 to 3 minutes of rest. That feels very different from 20 light reps, and it's the heavy version that brings the benefit.
If you're new to strength training, don't start there. Spend the first four to six weeks with moderate weights and 10 to 15 controlled reps, learning the movements. Then move towards heavier sets. Stop each set with one or two good reps left in you; strength training for runners should never leave you limping into the next run.
Through the season
Strength work changes with the running phases, like the running itself.
| Phase | Strength focus | Sessions a week |
|---|---|---|
| Preparation and Base 1 | Adaptation: learn the movements, moderate weights, more reps. | 2 |
| Base 2 to 3 | Maximum strength: heavier sets, fewer reps, slow descents. | 2 |
| Build | Keep the heavy work, add springiness (jumps, bounding). | 1 to 2 |
| Peak | Maintenance: a short session, a few heavy sets, no new exercises. | 1 |
| Race week | Nothing heavy. Mobility only. | 0 |
Strength fades slowly: one short session a week is enough to keep most of what you built. That's why the work shifts from building strength in base to keeping it as the running gets more specific.
Fitting it around running
- Keep hard days hard. Do strength on the same day as a hard run, a few hours after it if you can, so your easy days stay easy.
- Protect key sessions. Avoid heavy leg work the day before a long run or a hard climb session: legs need about 48 hours to be fresh again.
- Count it as training. Two 40-minute sessions are more than an hour of training a week. Count them in your weekly hours, or the week will be heavier than the plan says.
- Short is fine. 30 minutes with five exercises done well beats an hour done rushed.
A sample session (base phase)
About 40 minutes, after a 5-minute warm-up (easy cycling or skipping, a few bodyweight squats and lunges).
- Bulgarian split squat: 3 sets of 6 per leg, heavy, 2 minutes rest.
- Romanian deadlift: 3 sets of 6, heavy, 2 minutes rest.
- Step-down from a knee-high box, 4 seconds down: 3 sets of 8 per leg.
- Straight-knee and bent-knee heel raises on a step: 3 sets of 10 each, slow.
- Circuit, 2 rounds: side plank with leg lift 30 seconds per side, dead bug 10 per side, banded side steps 10 per side.
Strength sessions in MyTrainingDesk
In MyTrainingDesk your annual plan sets a strength phase for each week (adaptation, maximum strength, maintenance), and strength sessions count in the week's hours. Build them from the exercise library as single exercises, supersets or circuits, follow them set by set with rest timers and exercise videos, or ask the coach to write one.
Sources
- Rønnestad BR, Mujika I. Optimizing strength training for running and cycling endurance performance: a review. Scandinavian Journal of Medicine & Science in Sports, 2014; 24(4): 603–612.
- Lauersen JB, Bertelsen DM, Andersen LB. The effectiveness of exercise interventions to prevent sports injuries: a systematic review and meta-analysis of randomised controlled trials. British Journal of Sports Medicine, 2014; 48(11): 871–877.