Of everything you can measure in a young footballer, one number keeps coming out on top. In a longitudinal study of academy selection, 30-metre sprint speed was the single best predictor of who got picked — and adding more measures, or tracking how fast those measures improved, didn’t make the prediction any better. A separate study following nearly three thousand players found the same shape: those who went on to play professionally were faster, jumped better and covered more ground from early adolescence onward. Height and body mass, meanwhile, showed no such difference.
That last detail is worth pausing on, because it quietly kills a common assumption. The physical advantage that matters isn’t being big. It’s being fast.
Then comes the complication, and it’s a big one. Predicted selection is doing a lot of work in that sentence. Selection is a decision made by adults, and adults reliably pick fast children — so the finding partly describes how scouts behave, not only how players develop. And at 13, a large share of who is fast is simply who is further through puberty and who was born early in the selection year. A stopwatch at that age is measuring training, genetics and calendar all at once, and it cannot tell you which is which. That’s exactly why the same research literature keeps finding that the best junior is usually not the best senior.
So what survives all that hedging?
Speed is specific, and it is trainable. Not infinitely — genetics set a range — but meaningfully, and more than most people assume. Sprinting is a skill with technique: how you apply force into the ground, posture, arm drive, how you accelerate out of the first three steps. Those improve with practice at quality, which means fresh legs and full recovery between efforts, not exhausting yourself.
Match speed is not track speed. A football match almost never asks for a 30-metre straight-line run. It asks for five metres, a stop, a turn, a reaction to something that just happened. Change of direction and reaction are their own trainable qualities — that’s the whole point of the agility & reaction routine, and why it insists on sharp cut angles and reacting to a sound rather than moving on your own count. Straight-line work has its own routine; a game wants both.
The honest part: speed work is high-force work, which makes warming up properly non-negotiable — movement prep exists for that. And the number itself deserves no ceremony. A 13-year-old’s sprint time is a snapshot of a body mid-construction, not a verdict on the player they’re becoming. Train the mechanics, keep the reps clean, and don’t let a stopwatch tell a child who they are.