5 Strength Training Myths Runners Need to Stop Believing
The running world loves a simple rule. Unfortunately, some of the most repeated strength advice out there doesn’t hold up when you actually look at the research.
As a physiotherapist specializing in running injuries, I hear these myths regularly from patients, from runners online, and in content circulating in the running community. So, let’s clear them up!
Read along to find out about five strength training myths worth challenging and what the evidence actually says.
Myth 1: “Heavy lifting will make you slow”
The fear: Lifting heavy weights will make you bulk up. As a result, you fear you’ll slow down and lose the lightness that makes you a runner.
The reality: Gaining significant muscle mass is hard, and it doesn’t happen overnight. It requires eating more calories, adding more protein to your diet, progressive overload, and consistent training over months or years, amongst other things. Runners who strength train 2-3 times per week while maintaining high running volume are not going to accidentally bulk up.
Research consistently shows that higher-load strength training improves running economy and performance (Balgrove et al., 2018). These are two things that directly make you faster and more efficient. What’s important is progressive loading with intention, not lifting heavy for the sake of it.
Myth 2: “Runners just need light weights and high reps”
The fear: Runners need endurance, so training should mimic that. That’s why some runners have been told that high reps, low load, lots of fatigue is the way to go.
The reality: Running is already an endurance exercise. As runners, what we’re trying to get out of our strength training is strength and muscle growth. Endurance-style lifting doesn’t produce the proper adaptations that transfer to better running performance. What we need is a heavier load that will challenge us with fewer reps. Think 8–12 reps range with a couple reps left in the tank. This is where the meaningful performance gains are for most runners.
It’s also important to note that heavy resistance training creates important adaptations in how your muscles and nervous system work together. As a result, your mechanical efficiency will improve. This includes making your tendons stiffer and stronger, which is an important outcome for runners (Llanos-Lagos et al., 2024).
Myth 3: “You need to train multiple times a week to see results”
The fear: If you’re not in the gym four or five days a week, you’re wasting your time.
The reality: Performing two sessions per week is well-supported in the literature and sufficient for most recreational runners to build meaningful strength (Balgrove et al., 2018). Consistency over frequency, always. Two quality sessions you can sustain will always beat five sessions you can’t.
Myth 4: “You need a gym to strength train as a runner”
The fear: Without a gym membership, proper strength training is off the table.
The reality: At-home strength training exercises with minimal equipment can absolutely tick the boxes. In the early stages of building a strength habit, bodyweight exercises might even be sufficient for runners. What’s important is that you keep progressing the load as you gain strength so you don’t reach a plateau.
A gym can be helpful in some instances, but it’s not the barrier most people think it is. Don’t let perfect be the enemy of good here.
Myth 5: “If you don’t feel the burn, it’s not working”
The fear: Unless you’re exhausted and burning, you haven’t done enough.
The reality: Strength doesn’t require suffering. The burn you can feel with some exercises is not a reliable marker of effective stimulus. Strength adaptations happen well below that threshold. What you should look for instead is finishing your set when the range of motion or speed decreases for a given exercise. This can come with or without a burn.
To Sum Up
Strength training is one of the most evidence-backed tools for injury prevention and performance in runners. That said, the way it’s often talked about puts up unnecessary barriers.
If you’re a runner who’s been avoiding strength work or doing it in a way that isn’t serving you, I hope this helps reframe it.
Do you want more evidence-based running content?
Follow @shape.physio on Instagram for regular posts on running injuries, strength for runners, and making sure you can run long-term.
Let me know in the comments if any of these myths surprised you or if there are any you don’t agree with!
Happy Running,
April :)
References:
Blagrove, R. C., Howatson, G., & Hayes, P. R. (2018). Effects of Strength Training on the Physiological Determinants of Middle- and Long-Distance Running Performance: A Systematic Review. Sports medicine (Auckland, N.Z.), 48(5), 1117–1149. https://doi.org/10.1007/s40279-017-0835-7
Llanos-Lagos, C., Ramirez-Campillo, R., Moran, J., & Sáez de Villarreal, E. (2024). Effect of Strength Training Programs in Middle- and Long-Distance Runners' Economy at Different Running Speeds: A Systematic Review with Meta-analysis. Sports Medicine, 54(4), 895–932. https://doi.org/10.1007/s40279-023-01978-y
