Strength training for runners: does lifting actually make you faster?

For decades the fear was that lifting weights would make runners heavy and slow, stealing energy from the miles that matter. The research has comprehensively retired that idea. If anything, skipping strength work is one of the most common ways recreational runners leave free speed and durability on the table.

The headline finding: better running economy

Running economy is how much oxygen and energy you burn to hold a given pace. Improve it and you can run faster, or run the same pace more easily, with no change in your engine. It is one of the strongest predictors of distance performance, and strength training improves it reliably.

Balsalobre-Fernández et al. (2016) pooled controlled trials in highly trained runners and found a large beneficial effect on running economy. Blagrove et al. (2018), a systematic review of 24 studies in 469 trained middle and long distance runners, put the typical improvement in the region of 2 to 8 percent after 6 to 20 week programmes. For a trained runner, a few percent of economy is a serious chunk of race time.

It shows up in race results, not just the lab

The classic demonstration is Paavolainen et al. (1999). Replacing about a third of endurance training volume with explosive strength work for nine weeks improved 5 km time-trial performance, running economy, and maximal anaerobic running velocity, with no change in VO₂max. The gains came from the neuromuscular system, not the aerobic one. Beattie et al. (2014), reviewing competitive endurance athletes, concluded that strength training improved time-trial performance, economy, and VO₂max.

Why it works, and why you will not bulk up

This is the key mechanism, and the answer to the oldest objection. The benefit comes from improved neuromuscular qualities, that is, force production, leg stiffness, and the rate at which your muscles can apply force to the ground, not from bigger muscles. Beattie et al. (2017) followed distance runners for 40 weeks and improved maximal strength, reactive strength, economy, and velocity at VO₂max, explicitly without any added muscle mass. Blagrove et al. (2018) likewise found body composition largely unaffected. Runners get stronger and stiffer in the useful, spring-like sense, while staying light.

What kind of strength work is best?

Heavy and explosive both work, and combining them works best. Llanos-Lagos et al. (2024), a meta-analysis of 38 studies and 894 runners, found that high-load training had a moderate effect on running performance and that combining methods, heavy resistance plus plyometrics, had a large effect, outperforming any single approach. Rønnestad and Mujika (2014) reach the same practical conclusion in their review of strength training for endurance.

Does it interfere with your running?

The so-called interference effect, the worry that strength and endurance adaptations cancel each other out, is not a practical barrier for distance runners. Across the reviews, VO₂max and lactate markers were neutral to improved, never impaired, when runners added heavy and explosive work. Interference mainly concerns athletes chasing maximum muscle growth and maximum endurance at once, which is not what a runner’s strength programme looks like. Strength work is a partner to your easy aerobic base and your hard VO₂max sessions, not a competitor for them.

The injury-prevention bonus

Even setting performance aside, there is a strong case. Lauersen et al. (2014), a meta-analysis of 25 randomised trials covering more than 26,000 participants, found that strength training reduced overall sports injuries to less than a third, and roughly halved overuse injuries. Given how many runners lose months to overuse problems, that alone justifies two short sessions a week.

An honest caveat

The effect is not guaranteed in every case. Vikmoen et al. (2016), in a study of female endurance athletes, found heavy strength training raised leg strength substantially but did not change running economy, VO₂max, or a 40-minute all-out test under fresh conditions, though related work suggests benefits can appear later in prolonged efforts when fatigue sets in. Results depend on the protocol, its duration, and how performance is tested. But the weight of evidence is consistent and strong: for most runners, getting stronger makes you faster and more durable.

Frequently asked questions

Related reading: Zone 2 training for runners: what the research actually shows.