Effects of Strength Training on Postpubertal Adolescent Distance Runners.

Strength training is well established as a way to improve running economy and power in adult distance runners, but whether the same holds for adolescents has been unclear. This randomised controlled trial compared a 10-week program of twice-weekly plyometric, sprint, and resistance training added to normal running against a control group who continued their usual training only. The strength training group showed small improvements in running economy, a very likely benefit in sprint speed, and a possible benefit in maximal force production, without apparent harm to body composition or aerobic measures like maximal oxygen uptake. The findings suggest added strength work may offer modest performance-related benefits in postpubertal adolescent runners, but the trial was small, with only 18 of 25 enrolled participants completing it, so the results should be read as preliminary rather than conclusive.

If you're a teenage distance runner, or support one, you might wonder whether adding strength exercises like jumping, sprinting, and resistance training to running actually helps. This study put that question to the test in runners over 17 years old on average, comparing those who added two weekly strength sessions to their running for 10 weeks against those who just kept training as usual. The runners who did extra strength training saw small improvements in running economy, meaning they used oxygen a bit more efficiently at a given pace, along with faster sprint times and stronger leg force.

Their body composition and overall fitness markers didn't seem to be negatively affected. These results are encouraging for the idea that strength training can complement running in young athletes, but the study only had 18 participants finish, which is a small number. That means the findings give an early signal rather than a firm answer.

This is a summary of research, not medical advice. Talk to your own healthcare provider about anything affecting your care.

This trial addresses a gap in the running literature: while strength training's benefits for running economy and neuromuscular qualities are well documented in adults, evidence in postpubertal adolescent runners has been limited. The study randomised 25 adolescent distance runners (13 female), paired by sex and running economy, to a 10-week strength training group (plyometric, sprint, and resistance work twice weekly added to normal running) or a control group continuing usual training, with 18 participants (9 per group) completing outcome testing. The strength training group showed small improvements in running economy (3.2%-3.7%, inferred as possibly beneficial) across submaximal speeds, a very likely benefit in 20-m sprint time, and a possible benefit in isometric quarter-squat maximal voluntary contraction, while changes in body composition and maximal oxygen uptake were trivial or small.

This informs the question of whether strength training can be layered onto adolescent endurance programs without compromising aerobic adaptations, though the abstract does not report formal between-group statistical significance testing for all outcomes, and effect sizes were often small. The main limitation is the small completed sample (n=18) and the loss of over a quarter of enrolled participants, which constrains confidence in generalising these preliminary findings to broader adolescent running populations.