Training

The warm-up: what actually works before you train.

By Luigi · 5 min read

Most warm-ups I see in gyms are either skipped entirely or built on habit rather than evidence — five minutes on a bike, then straight into working weight, or the opposite, ten minutes of static stretching that research has actually linked to worse performance, not better. Neither is doing what people think it's doing.

Warming up works — the evidence is solid

A systematic review pooling decades of research on warming up found a consistent, measurable performance benefit across sports and tasks when the warm-up was active and progressive^[1]. That part isn't in question. The question is what kind of warm-up actually earns that benefit, and the answer isn't "more stretching."

Static stretching can work against you

A systematic review of the acute effects of stretching found static stretching held immediately before a max-effort lift or sprint produces a small but real average drop in performance — around 3.7% — while dynamic stretching done the same way was associated with a small average gain, around 1.3%^[2]. The likely mechanism for the static-stretching dip is that holding a muscle in a stretched position temporarily reduces its ability to produce force — the opposite of what you want right before a heavy set. This doesn't mean stretching is bad; it means the timing matters. Save long static holds for after training or for a separate mobility session, not as the thing you do two minutes before your top set.

A separate, more targeted review of dynamic stretching specifically found consistent evidence it improves range of motion and subsequent strength, power, sprint and jump performance, likely through a mix of reduced muscle-tendon stiffness and a genuine warming effect from the movement itself^[4]. That's the practical takeaway: dynamic, not static, is the stretching that belongs in a pre-lifting warm-up.

What actually prepares you to lift

A systematic review focused specifically on upper-body warm-ups found strong evidence that high-load, dynamic warm-ups — moving through the actual pattern you're about to train, building up in load — improved subsequent power and strength performance, while passive approaches like heat packs showed little to no benefit^[3]. In plain terms: ramping up through lighter sets of the exercise you're about to do beats almost anything passive, and beats static stretching outright when strength or power is the goal.

What I actually tell clients

• Move first, stretch later. A few minutes raising your heart rate and moving the joints you're about to train beats static stretching as prep for lifting.
• Ramp the actual lift. Light sets of the exercise itself, building toward your working weight, is the single best warm-up for that exercise — better than unrelated cardio.
• Save long stretches for after. If mobility work matters to you — and for some people it genuinely does — put it at the end of the session or on its own, not right before you need maximum force output.
• Don't skip it, but don't overdo it either. Five to ten minutes of progressive ramp-up gets you most of the benefit. It doesn't need to be a 25-minute routine to count.