How many strides does it take to reach top speed out of the blocks?
The honest range coaches actually use, why it moves with the athlete, and how to look for the answer on your own film instead of a textbook number.
Coaches ask this expecting a single number, and the honest answer is a range, because the number moves with strength, block spacing and how hard the athlete drove out. For most high school sprinters, top speed shows up somewhere between 20 and 40 metres in, which works out to roughly 15 to 25 strides after the first step. A stronger or older athlete usually takes longer to get there, not less, because they can keep adding speed for longer before they run out of force to add.
Why the range is wide
- A weaker or younger athlete accelerates for fewer strides and hits a lower top speed sooner, simply because there is less force behind each push.
- Wider or narrower block spacing changes how much ground the first two or three steps cover, which shifts everything after it by a stride or two.
- Fatigue late in a season or a meet shortens the acceleration phase even in an athlete who normally holds it longer.
Finding the real number on your own athlete
The Film Room's sprint setting is the one that reports top speed, and it needs two marks a known distance apart on the ground to do it. The block-start setting does not calculate a speed at all, it only reports the first six steps, so if you want to see the whole transition, film the run continuously and put it through the sprint setting rather than switching partway.
What it will not do is point at the exact stride where your athlete stopped accelerating. Speed comes out as one average between the two marks you set, so a pair of marks spanning the whole run gives you one number for the whole run, not a curve. To actually see where the plateau is, mark shorter, overlapping stretches, ten metres at a time, and compare the numbers between them.
Cadence is the easier proxy, and it comes straight from foot strikes rather than from marks you have to place. Top-speed sprinting for most athletes sits around 260 to 300 steps a minute. Once cadence on the film stops climbing and holds flat for a few strides, that is roughly where top speed arrived, whatever stride count a textbook would have told you.
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Related
How long should a high jumper's approach be?
The honest answer is set by how many strides it takes an athlete to reach a speed they can still control on the curve, not a number to copy.
Read →How many steps should a hurdler take to the first hurdle?
Seven and eight both show up at the highest level of the sport, so the number that matters is not tradition, it is whether the athlete arrives at the mark running over the barrier rather than jumping it.
Read →How long should a long jump run-up be?
Long enough to reach the speed the athlete can still take off from, and not one stride longer.
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