Warming Up: What Works and What's Filler
Introduction
Warming up is one of those things everyone knows they should do and almost nobody knows why. The version inherited from PE class — jog a bit, then stretch each muscle for ten seconds — is still the most practised, and it turns out much of it doesn't do what it's credited with.
What actually works takes five to ten minutes, and it's different from what most people do.
Warming up doesn't prevent injuries on its own. It prepares the body to work better, which is reason enough.
What a warm-up actually does
It raises muscle temperature. Literally: a warmer muscle contracts and relaxes faster, and produces more force. Hence the name.
It increases blood flow to the muscles about to work.
It reactivates coordination. Rehearsing the pattern you're about to perform improves the technique of your first sets, which are usually the worst of the session.
It prepares your head. Switching from desk mode to training mode has an attentional component that's underrated.
What it does not demonstrably do is prevent injuries on its own. The evidence on prevention points elsewhere: complete neuromuscular programs — like FIFA 11+, which include strength, balance and landing control over several weeks — do consistently reduce injuries. A generic five-minute warm-up is not that.
The static stretching myth
This is the best-established part and the hardest to uninstall.
Stretching a muscle and holding the position before training transiently reduces strength and power. The effect is well documented in meta-analyses, and it's larger when the stretch is held beyond about 60 seconds. Short stretches within a warm-up that then includes active work have a small or null effect.
And on injuries: reviews don't find that pre-exercise stretching reduces them. It was taught for decades on that justification and the data don't support it.
This doesn't mean stretching is bad. It means its place is elsewhere: at the end of a session, or in a separate slot, if your goal is gaining range of motion.
The warm-up that does make sense
It comes in three phases and takes five to ten minutes.
1. Raise the temperature (3-5 minutes)
Something continuous and gentle: brisk walking, cycling, skipping, stairs. The criterion is simple: until you're breathing a bit harder and your body feels warm. This isn't training, it's preparation.
2. Dynamic mobility (2-3 minutes)
Controlled movements through the range you're about to use, without holding positions: arm circles, leg swings, hip and trunk rotations, bodyweight squats. The difference from static stretching is that here the muscle moves rather than being held long.
Choose according to what you're training: upper body means shoulders and thoracic spine; lower body means hips and ankles.
3. Ramp-up sets (the most important part)
This is the part almost nobody does and the one that pays off most. Before your working weight, do the same exercise with increasing loads.
For example, if you're squatting 60 kg: one set with the empty bar, one with 30, one with 45, and only then your working sets. Few reps — 5, 3, 2 — without tiring yourself.
This warms up exactly what you're going to use, rehearses the pattern, and tells you how your body is that day. For the first exercise of the session it's essential; for the following ones, one light set or none usually suffices.
How much to warm up, case by case
Heavy strength: the longest warm-up, mainly because of the ramp-up sets.
Easy cardio or walking: practically none. The first few minutes at a low pace are the warm-up.
Intense cardio or intervals: yes, and quite a bit: going into a maximal effort cold feels awful and performs worse.
Sports with cutting and jumping: this is where the complete neuromuscular program makes sense and has evidence.
Early morning or cold weather: more time. Body temperature is lower and the body is stiffer.
And cooling down
Briefly, because the answer is short: it doesn't have the support it's credited with. Reviews don't find that walking or stretching afterward meaningfully reduces delayed muscle soreness or speeds recovery.
Easing off gradually after intense effort is sensible so as not to stop abruptly. But if you skip it, nothing happens.
Common mistakes
Stretching cold as a warm-up. The classic error, and uncomfortable besides.
Warming up so much you arrive tired. Ten minutes is plenty. If you finish the warm-up sweating and drained, that was training.
Skipping the ramp-up sets. The most useful part, and the first thing cut when rushed.
Always warming up the same way. Your warm-up should resemble what comes after it.
Believing it protects you from everything. It doesn't replace sensible load progression, which is what actually prevents injuries.
Conclusion
A good warm-up is short, specific and ends up resembling the exercise you're about to do. None of that involves holding stretches cold.
Try this structure in your next session: three minutes of something that raises your pulse, two of dynamic mobility, and two or three ramp-up sets of your first exercise with increasing load. You'll notice the difference on your first working set — which is exactly where things used to feel inexplicably heavy.
References
- Simic, L., Sarabon, N., & Markovic, G. (2013). Does pre-exercise static stretching inhibit maximal muscular performance? A meta-analytical review. Scandinavian Journal of Medicine & Science in Sports, 23(2).
- Behm, D. G., et al. (2016). Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals. Applied Physiology, Nutrition, and Metabolism, 41(1).
- Fradkin, A. J., Zazryn, T. R., & Smoliga, J. M. (2010). Effects of warming-up on physical performance: A systematic review with meta-analysis. Journal of Strength and Conditioning Research, 24(1).
- Herbert, R. D., de Noronha, M., & Kamper, S. J. (2011). Stretching to prevent or reduce muscle soreness after exercise. Cochrane Database of Systematic Reviews, 7.
- Sadigursky, D., et al. (2017). The FIFA 11+ injury prevention program for soccer players: A systematic review. BMC Sports Science, Medicine and Rehabilitation, 9.