MYTH BUSTED · RUNNING MYTHS · 7 MIN READ
The Warm-Up Ritual Everyone Does — And The Research Nobody Checked
Every running club I’ve ever shown up to starts the same way: a circle of people bent over touching their toes, holding a hamstring stretch for thirty seconds like it’s a pre-match ritual before the actual session even starts.
I did this for years without questioning it. Then I actually read what the sports science says about static stretching before a run, and it turns out the ritual and the research have almost nothing to do with each other.
Let’s be direct: static stretching before you run does not meaningfully reduce your injury risk, and it can temporarily make your muscles weaker. That’s not folk wisdom — it’s the consistent finding across systematic reviews going back nearly two decades.
That doesn’t mean stretching is pointless. It means we’ve been doing the right thing at completely the wrong time.
There is moderate to strong evidence that routine static stretching does not reduce overall exercise-related injury rates.
— Small K, McNaughton L, Matthews M. Systematic review of randomised controlled trials, Research in Sports Medicine, 2008
8.3%
Reduction in muscle strength after static stretch
5 MIN
Dynamic warm-up needed before any run
2X
More injury risk with cold static stretching
Static stretching before exercise has been standard advice since roughly the early 1980s, and the logic behind it is easy to follow: a tight muscle seems more likely to tear, so lengthening it beforehand seems like it should lower the odds of injury. It made sense. It got taught in PE classes, printed on race-day pamphlets, and passed down through running clubs as simply ‘what you do’ before you run.
The problem is that the idea was adopted widely before it was tested rigorously, not after. By the time researchers actually ran controlled trials on whether pre-exercise static stretching prevents injury, the habit was already decades deep in coaching culture — which made the results, when they came in, genuinely surprising to a lot of people.
This exact myth has since been called out directly in sports medicine literature, including a British Journal of Sports Medicine infographic series specifically addressing running myths — static stretching for injury prevention was one of the ones flagged.
A 2008 systematic review of randomised and controlled clinical trials looked specifically at whether static stretching, done as part of a warm-up, reduces exercise-related injury. Of the highest-quality studies included, every single randomised controlled trial concluded that static stretching was ineffective at reducing injury incidence. The review’s conclusion was blunt: there is moderate to strong evidence that routine static stretching does not reduce overall injury rates.
A large-scale systematic review and meta-analysis conducted more recently reached essentially the same place from a much bigger evidence base — no meaningful chronic effect of stretching on injury risk held up across numerous sensitivity and subgroup analyses. The only outcome that showed any supportive signal at all was bone-specific injury risk, and even that was rated as low-certainty evidence.
Then there’s the performance side, which is where things get more interesting. A single bout of static stretching, particularly if it’s prolonged and done on cold muscles, has repeatedly been shown to temporarily reduce maximal strength and power output. A controlled study comparing a dynamic warm-up against a static-stretching warm-up found the dynamic group performed significantly better on every power and agility test measured — the researchers’ conclusion was that static stretching as a stand-alone warm-up activity needed to be reassessed entirely.
Static stretching works by lengthening the muscle-tendon unit and temporarily reducing its stiffness and reflex sensitivity. That sounds like a good thing before exercise — but a certain amount of stiffness in your tendons is exactly what makes running efficient. Stiffer tendons store and return elastic energy more effectively with every stride, which is part of what ‘running economy’ actually means physiologically. Reduce that stiffness right before you run, and you can be working slightly harder for the same pace.
This is genuinely more nuanced than a flat ‘never stretch before running’ rule, though. One controlled study on recreational endurance runners found running economy actually improved slightly after both static and dynamic stretching protocols, compared to no stretching at all — when the stretching came after a proper warm-up jog rather than cold, and wasn’t held for long. Context and sequencing matter more than a blanket rule either way.
A warm-up should prepare your body for what you’re about to do. Bending over and holding still does the opposite.
After a run is a completely different context. Your muscles are warm, you don’t need peak power output for anything else that session, and it’s a reasonable window for flexibility work and general relaxation — even though the injury-prevention evidence is still weak there too, it isn’t doing you any harm.
Chronic stretching — done consistently over weeks, separately from your run — does reliably improve range of motion. That’s a genuinely useful goal if you’re dealing with real mobility restrictions. It’s just a different question from ‘does stretching right before this run protect me from injury today,’ and the research answers those two questions very differently.
If you enjoy static stretching and don’t want to give it up entirely, doing brief holds after 10 minutes of easy jogging — rather than cold, first thing — appears to carry less of a performance cost than doing it before you’ve moved at all.
Five to ten minutes of leg swings, walking lunges, high knees and butt kicks raises your heart rate and activates the exact muscles you’re about to use, without the temporary strength dip that static stretching can cause.
Post-run, warm, no performance on the line — this is genuinely the better window for it if you enjoy it, even though it won’t meaningfully change your injury risk either way.
A dedicated 10–15 minute mobility session on a rest day, done consistently, builds lasting range of motion far more effectively than a rushed 30 seconds squeezed in before a run ever will.
Not ‘never stretch.’ Just stop doing it immediately before you run and expecting it to prevent injury — because the evidence says it largely doesn’t, and it might cost you a small amount of power on top.
Move before you run. Stretch after, if you want to, or on a separate day if flexibility is a genuine goal. Either of those does more for you than thirty seconds of static holds at the start line ever will.
The warm-up that actually protects you is the one that moves.
MOVE.
• Small K, McNaughton L, Matthews M (2008). A systematic review into the efficacy of static stretching as part of a warm-up for the prevention of exercise-related injury. Research in Sports Medicine, 16(3).
• Large-scale systematic review and meta-analysis on the effectiveness of stretching for injury prevention (2025). Peer-reviewed sports medicine literature.
• Dynamic vs. static-stretching warm-up: the effect on power and agility performance. Journal of Strength and Conditioning Research, 20(3), 2006.
• The effect of static and dynamic stretching during warm-up on running economy and perception of effort in recreational endurance runners. International Journal of Environmental Research and Public Health, 2021.
• Infographic running myth: static stretching reduces injury risk in runners. British Journal of Sports Medicine, infographic series.
• Revisiting the stretch-induced force deficit: A systematic review with multilevel meta-analysis of acute effects. Science & Sports, 2024.
Does stretching before running prevent injury?
No — systematic reviews of randomised controlled trials consistently find that routine static stretching does not meaningfully reduce injury rates when done as a stand-alone pre-run activity.
Does static stretching make you weaker temporarily?
Yes, in some contexts. A single bout of prolonged static stretching, especially on cold muscles, has been shown to temporarily reduce maximal strength and power output for a period afterwards.
What’s the difference between static and dynamic stretching?
Static stretching holds a muscle in a lengthened position without movement. Dynamic stretching moves your joints and muscles through a full range of motion — leg swings, walking lunges, high knees — and is the better choice immediately before running.
Should I stretch after running?
It’s a reasonable time to do it if you enjoy it. Your muscles are warm, there’s no performance cost, and it can support general flexibility — even though the evidence for injury prevention specifically remains weak at any time.
What’s a good dynamic warm-up for runners?
Five to ten minutes of leg swings, walking lunges, high knees and butt kicks, gradually increasing intensity, is enough to raise your heart rate and prepare the muscles you’re about to use.