The 40-Yard Sprint
Here, we measure speed in three parts — acceleration, transition, and top-end. Each is a different ability and each is trained differently; a single total time can't separate them, but the splits can.
What this looks like
You start from a stance behind the line and sprint forty yards through electronic timing gates — two attempts, fully recovered between, with plenty of room past the line to slow down safely. Most athletes have run a 40 before. Very few have seen theirs broken into segments, which is where the useful information is.
Why we test it
Because the 40 is really three tests wearing one name. With gates at 10, 20, and 40 yards, one sprint gives us:
- 0–10: acceleration — how fast you build speed from a standstill
- 10–20: transition — how you shift from driving to upright sprinting
- 20–40: top speed — how much velocity you reach and hold
Two athletes can run the same 4.9 and be opposites: one wins the start and fades, the other builds slowly and finishes flying — the same number, with opposite training plans behind it.
What we're really looking for
The gates record the time; we're watching how the time gets made.
- How do you leave the line — low and pushing, or standing straight up?
- Does the run build smoothly through the middle?
- At top speed, do you look relaxed — or like you're fighting to hold it?
- Do the three segments agree with each other?
What good looks like
In the run itself, we want to see a patient, powerful start, a smooth rise to upright running instead of a sudden stand-up, and top-end mechanics that look easier the faster they get.
For football players, the 40 is the native language of speed, so the reference points are worth knowing: the fastest 40s ever recorded at the NFL Combine sit around 4.2 seconds, receivers and defensive backs commonly run in the 4.4s and 4.5s, and linemen typically land around 5.0. Those are the far end of the pathway — useful perspective, not expectations for a developing athlete. For most other sports, the splits matter more than the total, because games rarely ask anyone to run forty straight yards.
Two things to keep in mind when comparing times: hand timing reads a couple tenths faster than electronic gates, so most quoted 40s aren't comparable to tested ones. And your time should be read against your age, sex, and sport — then against your own retest, which is the comparison that matters most.
When the number and the ability don't match
A strong 10 with a fading finish points to top-speed mechanics and elasticity. A slow start with a strong finish points to strength and acceleration. And sometimes the sprint isn't the story at all — the time is being produced by what's underneath it: ankle range that sets your shin angle, hip mobility that sets your stride, trunk control that keeps force pointed forward.
What we do about it
Your splits decide the plan: start work, top-end work, or the layer beneath both. One more thing we hold to: we don't run athletes at near-top speed on day one without sprint history — max velocity is safe when it's prepared for. If the 40 isn't right for you yet, shorter segments give us the same answers at lower cost, and the 40 becomes a goal instead of a gamble.
What's underneath this number
The 40 is built from capacities most speed training never looks at. That's the layer we map next.