Strength Training for Runners: Why Every Runner Should Do It

Why runners should do strength training

With each step you absorb your own body weight several times. That sounds abstract, but do the math: for an endurance run of 10 km you take about 8,000 to 10,000 steps. If your muscles, tendons and joints cannot absorb that load properly, the risk of overuse injuries increases significantly.

Strength training helps in four ways:

1. Better running economy

Running economy is the amount of energy you need to maintain a certain pace. Stronger muscles control muscle fibers more efficiently: you run more efficiently at the same pace. Research shows that a targeted strength program of 8 weeks made runners on average 2.5% faster on the 10 km. Not by running faster, but by moving more efficiently.

2. Fewer injuries

Running is a one-sided, repetitive strain. Weak hips, unstable knees or underdeveloped gluteal muscles are often the silent cause behind knee complaints, Achilles tendon injuries and shin pain. Strength training tackles those weak links directly.

3. Stronger tendons and bones

Tendons adapt more slowly than muscles. Targeted strength training, especially eccentric exercises such as eccentric calf raises, makes tendons more resilient and less sensitive to overload.

4. Better running technique when tired

At the end of a long run or race, your technique collapses. A strong core and strong glutes help maintain your posture when your legs are straining.

The interference effect: does it really exist?

You may have heard: strength training and endurance training "bite" each other. This is called the interference effect, first described by Dr. Robert Hickson in 1980. The theory is that endurance training via the AMPK pathway inhibits the mTOR pathway, the signaling pathway necessary for building muscle strength.

Sounds alarming, but in practice this is greatly nuanced. Three recent meta-analyses found that concurrent training (= the combination of strength and endurance sports) does not pose a significant obstacle to strength development, as long as the total training volume is in proportion to your recovery capacity. So most runners don't have to worry about this. The interference effect is especially relevant for top athletes who train at extremely high volumes.

The practical conclusion: you can easily combine strength training and running. It makes you a better runner. Not worse.

When do you do strength training: before or after running?

This is the most frequently asked question about combining both forms of training. The answer depends on your goal and the intensity of both sessions.

If you train on the same day

Running first, then strength training: This is the standard recommendation for most runners. Research by Kenji Doma shows that strength training for your legs then 'carry-over fatigue'. that affects your running quality for hours afterwards. Conversely, the effect is smaller.

Practical example: intensive running training in the morning, strength training in the evening. This works well.

Wait at least 6 hours between sessions if you combine heavy strength training with quality running training on the same day.

If you train on different days

That is ideal. Preferably do not plan strength training the day before an intensive running training (interval or tempo run). After a heavy leg training you need 48 to 72 hours before you can run optimally intensively again.

A workable weekly structure for 4 training days:

Which exercises are the most valuable?

Strength training for runners is not about building muscle mass. The goal is functional strength: strength that you use directly when walking. This means an emphasis on single-leg exercises (because running is a series of one-legged push-offs), compound movements and a strong core.

Lower body: the basics

Bulgarian split squat: The queen of single-leg exercises for runners. Trains quadriceps, glutes and hamstrings simultaneously, improving balance and revealing asymmetry between left and right. Start without weight, build up gradually.

Romanian deadlift (RDL) or single-leg RDL: Focuses on hamstrings and glutes. Two muscle groups that are often underdeveloped in runners. The single-leg variant adds balance and stability.

Goblet squat or back squat: Strengthens quadriceps, glutes and core. For runners, a depth of at least 90° desirable.

Step-ups: Functional and tax-friendly. Ideal if you have knee problems or want to build up carefully.

Eccentric calf raises: Essential for the health of your Achilles tendon and calves. Stand on the edge of the stairs, raise yourself on two legs, then slowly lower yourself on one leg. 3 sets of 10-15 reps, three times a week.

Core: underestimated but crucial

A strong core keeps your upper body stable while your legs move. Without core strength, your hip will sag when tired, leading to knee problems and an inefficient running posture.

• Plank + side plank: the base
• Dead bug: activates deep abdominal muscles without back strain
• Single-leg glute bridge: connects core and glutes
• Copenhagen plank: specific for hip abductors, highly preventive for knee complaints

Plyometrics (advanced)

Explosive exercises improve muscle-tendon stiffness and thus running economy. Think of box jumps, jump squats and ankle hops. Keep these sessions short and explosive, maximum 1à 2 times a week. Not suitable for beginners or in the build-up phase with high running volume.

How much strength training do you need?

For most runners, twice a week is ideal. That's enough to build strength and improve running economy without compromising running volume.

In busy training periods (just before a competition), once a week may be sufficient to maintain the achieved strength level.

Keep sessions concise: 30 to 45 minutes. Choose 4 à 6 exercises, focus on quality of execution, and build up the weight gradually over weeks. More is not better here.

Reps and weight

For runners, 3 sets of 8 to 12 repetitions work best. That is enough incentive for strength development without excessive muscle fatigue. Don't work to failure. You still need your legs.

When in the year?

Strength training is most valuable in the basic period, the weeks and months before a competition. As the race approaches and the running volume increases, scale back strength training from 2 to 1 times per week.

Never delete it completely. Also in the run-up to a marathon or Hyrox, maintain at least one strength session per week so as not to lose the strength you have built up.

→ More about building up to a specific goal? Read the page about periodization for runners.

Frequently asked questions

Summary

Strength training makes you faster, injury-free and more efficient as a runner. Twice a week, 30 to 45 minutes, with a focus on single-leg exercises for the lower body, eccentric calf raises and a strong core: that's the recipe. Plan it smartly into your week: preferably on separate days of your quality running training, or on the same day with at least 6 hours between both sessions.

→ More about how to optimally structure your training week? View the training hub or read more about periodization.