Should I stretch before a workout?

Yes, if you want to — the "static stretching ruins your workout" panic is overstated.

The internet swung hard from "always stretch" to "never stretch before lifting", and the second position is nearly as wrong as the first.

Does stretching before training weaken you?

A little, and only if you hold it a long time. The dose-response is clear:

• Holds under 30-60 seconds: essentially no meaningful effect.
• Holds of 60 seconds or more: a real strength decrement, up to about 7%.

And the best-controlled recent meta-analysis (83 studies) found no impairment of jumping, sprinting or throwing at all — jumping actually trended slightly positive. Even the famous 2013 meta-analysis that launched this whole scare only found a significant pooled effect for strength; its power and explosive-performance results were non-significant. That detail gets left out every time it's cited.

So: don't spend five minutes hanging in a deep hamstring stretch right before a heavy squat. Thirty seconds of easy stretching in a warm-up is not sabotaging you.

Does stretching make your muscles longer?

No — not the way people imagine. A 2025 meta-analysis of 65 studies found chronic stretching substantially raises your tolerance to stretch, and slightly reduces passive stiffness, but does not change muscle fascicle length. You mostly get more flexible by learning to tolerate the position, not by growing longer muscle.

The honest exception: extremely high-volume protocols (think ~75 minutes per muscle group per week) can produce real structural lengthening. Nobody stretches that much.

Does it prevent injury?

That's a separate claim with its own evidence — see the linked claim below.

Practical answer

Warm up properly. If you enjoy stretching, keep the holds short before lifting and save the long ones for afterwards or a separate session. The effect size here is small enough that your preference is a reasonable tiebreaker.