Evidence & Training · Running & Conditioning
Strength Training for Runners: What It Does and How to Start
How strength training improves running economy and performance, what it does for injury risk, and a simple twice-weekly plan for runners.
Many runners avoid the weight room, worried that lifting will make them heavier, stiffer or slower. The research points the other way: strength training is one of the better-supported ways to improve running performance, and it does so without the weight gain runners fear.
The benefits are not about building big muscles. They come from making each stride more efficient and from making tissues more robust to the repetitive loading of running. Heavy lifting and plyometrics both play a role.
This article explains what the evidence shows and gives a practical way to add strength training to a running week.
Quick answer
Adding two to three strength sessions per week generally improves running economy by about 2–8% and tends to improve time-trial performance over 1.5–10 km, without negative effects on body composition [1] [2].
Strength training also substantially reduced sports injuries in a meta-analysis of randomized trials, while stretching did not [3].
Running economy and performance
Moderate evidenceA systematic review of 24 studies in middle- and long-distance runners found that strength training — heavy resistance, explosive resistance or plyometric — generally improved running economy by about 2–8% compared with running alone. Time-trial performance over 1.5–10 km and sprint qualities also tended to improve. VO2max, lactate measures and body composition were typically unaffected [1].
A meta-analysis focused on highly trained runners (VO2max above 60 ml/kg/min) found a large beneficial effect of strength programmes on running economy. Most used two to three sessions per week for 8–12 weeks, combining resistance exercises with jumps and short sprints [2].
Injury risk
Moderate evidenceA meta-analysis of 25 randomized trials across sports found that strength training reduced sports injuries to less than a third, and that overuse injuries could be almost halved by exercise programmes. Stretching, by contrast, showed no beneficial effect [3].
These trials were not limited to runners, so the exact effect in running is uncertain. But the direction is consistent with what coaches observe: stronger tissues tolerate training loads better.
Why it works without bulking up
Limited evidenceMuch of the improvement in running economy is thought to come from neuromuscular changes — better coordination, stiffer and more reactive tendons, and more force per stride — rather than from muscle growth. Body composition was not negatively affected in the reviewed studies [1].
Large muscle gains also require high training volumes and an energy surplus, neither of which fits a typical runner's week.
How to add strength training
Two sessions per week are enough for most runners. Focus on a few lower-body lifts (squats or split squats, deadlift or hip-hinge variations, calf raises), one or two upper-body pulls and presses, and a small dose of plyometrics such as jumps or bounds.
Use heavier loads for 3–6 reps on the main lifts once technique is solid, and keep sets short of failure so sessions do not wreck your legs. Schedule them on hard-run days (after the run) or on easy days, and avoid heavy lifting in the 48 hours before a key race.
Common mistakes
- 1
Using only light, high-rep circuits
Endurance-style lifting duplicates what running already provides. Heavier loads and plyometrics are what most studies used.
- 2
Lifting hard the day before key sessions
Schedule strength work so that it does not compromise your most important runs.
- 3
Relying on stretching for injury prevention
Stretching showed no injury-preventive effect, while strength training did [3].
Practical takeaway
- 1Add two strength sessions per week to your running.
- 2Include heavy lower-body lifts (3–6 reps) and a little plyometric work.
- 3Stop sets short of failure to protect run quality.
- 4Place lifting after hard runs or on easy days.
- 5Give it 8–12 weeks before judging the effect.
Conclusion
For runners, strength training is not a distraction from running — it is one of the most effective ways to run more efficiently and stay healthy. The evidence for running economy and injury reduction is consistent, and the time cost is modest.
Start with two short sessions a week, lift with intent, and let your running benefit.
References
- [1]Blagrove RC, Howatson G, Hayes PR. Effects of Strength Training on the Physiological Determinants of Middle- and Long-Distance Running Performance: A Systematic Review. Sports Medicine. 2018;48(5):1117–1149. Systematic review doi.org/10.1007/s40279-017-0835-7
- [2]Balsalobre-Fernández C, Santos-Concejero J, Grivas GV. Effects of Strength Training on Running Economy in Highly Trained Runners: A Systematic Review With Meta-Analysis of Controlled Trials. Journal of Strength and Conditioning Research. 2016;30(8):2361–2368. Systematic review and meta-analysis doi.org/10.1519/JSC.0000000000001316
- [3]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. Systematic review and meta-analysis of RCTs doi.org/10.1136/bjsports-2013-092538
This guide summarises published research for healthy adults. It is general information, not medical advice — if you have a health condition, injury or take medication, talk to a qualified professional before changing your training, diet or supplements.
