Strength Training for Runners (#161)

Strength training is one of the most effective complements to running for anyone aiming to get faster, become more durable, and reduce the risk of injuries. The question is no longer whether runners should incorporate strength training, but how it should be structured to maximize performance and improve running economy. Research clearly shows that heavy, well-planned strength training can enhance running economy, speed, and muscular capacity without negatively impacting oxygen uptake. For most runners, two to three sessions per week during buildup phases and one session per week to maintain benefits during the competition season are sufficient.

We previously published a broader article on strength training for endurance athletes, but this text is more specific for runners.

If you're out for a run and start chatting about strength training with the group, it'll likely split into two camps—and a bit of drama always adds some excitement to a session :D.

1. One camp advocates for run-specific strength: hill sprints, swamp runs, and avoiding comfortable paths. The idea is that terrain and steep sections build up structures and demand greater muscle use.
2. The other camp prefers to separate training: running means running, and strength has its own sessions outside of running. It's simply a more complementary approach.

Of course, there are those who fall somewhere in between and those who are entirely anti-strength (a dying breed, if you ask us), but here we focus on the two main camps.

Claiming that strength training is beneficial for all endurance athletes is an oversimplification. An 800-meter runner gains different advantages from strength training compared to an ultra-runner. Both should incorporate strength training, but for the ultra-runner, it's more often for injury prevention, while the middle-distance runner focuses more directly on performance improvement.

Strength training significantly enhances running economy (RE) in long-distance runners, with studies reporting improvements ranging from 2 to 8 percent.

“Generally, incorporating a strength training (ST) program lasting 6–20 weeks into a distance runner's routine tends to improve RE by 2–8%.”

It's crucial not to take the 2–8 percent as an exact performance boost or a directly proportional reduction in oxygen consumption, but it does correlate well. For each percent improvement in running economy, about a 0.7 percent decrease in oxygen cost can be expected at both maximal and submaximal running speeds.

“Other studies indicate that even slight changes in RE (around 1.1%) directly result in changes (about 0.8%) in sub-maximal and maximal running performance.”

Keep in mind that the common measurement error in running economy assessments is between 1–2 percent. Thus, results are statistically more reliable with an improvement in RE of at least about 2 percent.

Since the enhancements observed after 6–20 weeks of strength training fall within the 2–8 percent range, it's reasonable to conclude that strength training for at least six weeks is advantageous for running economy, particularly at higher speeds and race pace. The most significant effect is often observed at speeds around or above the pace that corresponds to roughly 75 percent of VO2max (about 85 percent of max heart rate), which, for many trained runners, aligns with marathon pace or slightly below.

Strength training generally does not affect your oxygen uptake (VO2max) measured in ml/kg/min. It might seem paradoxical since increased muscle mass should lower the value in ml/kg/min if absolute oxygen uptake doesn't change. However, studies often show that absolute VO2 (L/min) increases slightly while body weight also increases, meaning the value in ml/kg/min can remain unchanged.

Researchers note that training regimens in many studies are often a mix of intervals and strength — and intervals should increase VO2max. Many study participants were already seasoned runners with high training volumes, so it’s reasonable to assume that absolute VO2 should increase over 6–20 weeks. The fact that ml/kg/min remains unchanged is often explained by the increased body weight.

Example with our test runner:

• BEFORE – 5.00 L/min / 75 kg = 67 ml/kg/min
• AFTER WITH STRENGTH TRAINING (+2 kg body weight) – 5.15 L/min / 77 kg = 67 ml/kg/min
• AFTER WITHOUT STRENGTH TRAINING – 5.15 L/min / 75 kg ≈ 68.7 ml/kg/min (≈69 ml/kg/min)

In the example, the absolute oxygen uptake must have increased by about 0.15 L/min (+3%) over 12 weeks for ml/kg/min to remain unchanged as body weight increases.

The question then becomes: would the person have been better off without the strength training? Perhaps ml/kg/min would have increased more, but the improved running economy (2–8%) from the strength training means the legs often deliver better speed nonetheless. A high VO2max without sufficient muscular capacity to translate it into running stride provides limited competitive benefit.

VO2max — the pace you can sustain at your VO2max — is often more relevant for a runner than VO2max alone. vVO2max combines both running efficiency and the capacity to engage muscle fibers for high speed. A quicker vVO2max is directly linked to faster race times.

Research indicates a rise in vVO2max by approximately 2.6–4 percent following strength training. This enhancement is particularly crucial for shorter distances where speed is key, but it also impacts longer distance performance to different extents.

Combining a 2.6–4 percent increase in vVO2max with a 2–8 percent improvement in running economy gives us insight that performance can improve across a wide spectrum of speeds — from just below marathon pace to near maximal speed.

It's recommended to incorporate a heavier strength training block of 6–12 weeks directly after the competition season. This is because, initially, muscles become sore and can negatively impact running when they’re not accustomed to it, and also because the post-season period often involves a natural tapering, making it easy to introduce new stimuli.

A convenient setup is 2–3 shorter strength sessions per week during base training, reducing to one maintenance session per week during the competition season.

“Runners can decrease ST volume from 2–3 sessions per week (each focusing on the lower limb) in preparatory phases to a single session each week during the competitive season without fearing a loss of adaptation due to the reduction in training density.”

The positive effects in studies come from strength training programs designed to increase:

• maximal strength,
• explosive strength,
• and reactive strength (jump exercises and drills focusing on the tendons' rubber band effect, SSC).

Six weeks are often sufficient for significant strength gains in runners, but training up to 20 weeks continues to be effective. After this, further focus on strength provides fewer marginal benefits for runners. This contrasts, for instance, with cyclists, where longer periods (at least 25 weeks) with 1–2 sessions per week may be most beneficial (source study).

In studies where positive effects are observed, often weights over 80 percent of 1RM are used—meaning more than 80 percent of the weight you can lift for one rep. The exercises are typically performed with 6–10 repetitions per set and 2–3 sets per exercise.

We showcase several exercises via our video library. There are five exercises that require minimal equipment. If you have access to a gym, classic full-body exercises like deadlifts and squats are excellent because they strengthen the core, legs, glutes, and back simultaneously.

An important detail: don't go to failure in the sets. Never do so many reps that you can't manage the last one. Going to failure extends the recovery time both physically and neurologically without any added benefits for run-specific strength.

A handy setup for two strength sessions per week:

The first session of the week features 10 reps per set, while the second session is more intense with 6-rep sets. As you get stronger and more accustomed, reduce the reps and increase the weight.

The studies have been neatly summarized in the following quote:

“Current evidence suggests that, in trained middle- and long-distance runners, resistance training can enhance running economy, muscular power factors, and running performance for distances between 1,500 and 10,000 m. Achieving these improvements requires 2 weekly sessions, with at least 48 hours in between, over a period of 6 to 12 weeks. These gains can be obtained using exercises aimed at enhancing maximum, explosive, and reactive strength, or a combination of these. Moreover, resistance training can be effective when replacing 20 to 40% of the usual volume of specific endurance work. No evidence currently associates resistance training with negative short-term effects such as body mass increase or overtraining symptoms.”

In short: most research suggests that as a runner, incorporating strength training is beneficial. Focus on your legs, hips, and core, aiming for 2–3 sessions per week during winter preparation if you compete more in the summer, and once a week during the competitive season for maintenance. A consistent strength training program for at least 12 weeks over the winter is recommended.

1 – The impact of resistance training on distance running performance. – 2003
2 – Effects of Heavy Strength Training on Running Performance and Determinants of Running Performance in Female Endurance Athletes. – 2016
3 – Effects of resistance training on performance in previously trained endurance runners: A systematic review. – 2018
4 – Strength Training for Middle- and Long-Distance Performance: A Meta-Analysis. – 2018
5 – Effects of Strength Training on the Physiological Determinants of Middle- and Long-Distance Running Performance: A Systematic Review – 2018

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