Why does my 400m runner die harder than everyone else in the last 100 metres?
A runner who leads at 300 metres and finishes fourth is not unfit, they are decelerating faster than the field, and that shows up on film before it shows up on the clock.
Your 400m runner is even with the field at 300 metres, sometimes ahead of it, and then loses two, three, four places in the final straight. It happens every meet. It is not a fitness problem in the way most coaches assume.
Everyone slows down. The question is by how much
Every 400m runner decelerates in the last 100 metres. Nobody sprints the whole race at top speed, the event is built around managing a controlled slowdown rather than avoiding one entirely. The athlete who wins is usually not the one who slows down least in absolute terms, they are the one whose slowdown is smaller than everyone else's. If your runner's drop-off is bigger than the field's, that is specific and worth filming, not a vague gap in conditioning.
What the fade actually looks like
- Stride length shortens first, before the runner or the coach notices anything is wrong.
- Cadence drops soon after, so the shortened stride is not being made up with faster turnover.
- Ground contact time lengthens, meaning each foot spends longer on the track producing less force.
- Trunk lean increases, as the runner folds forward at the waist instead of staying tall.
The order matters. A coach watching live usually sees the trunk lean first, because it is the most visible change, and assumes the problem is posture. On film, the stride length and ground contact numbers often start drifting a few strides earlier than the lean does. The lean is frequently the body compensating for a stride that has already shortened, not the original fault.
What to actually film
The sprint setting in the Film Room reports ground contact time, cadence, overstride and trunk lean, all from the same clip. Filming the same runner at the 300 metre mark and again in the final 30 metres, from the same spot each time, turns 'they died' into a number: how much cadence actually dropped, and whether the stride shortened before or after the lean showed up. A repeat-300s session on the Workout page, timed on the phone and sent to the training log, shows whether the same fade turns up in practice at training pace, or only under a meet's pacing.
A camera cannot tell you whether the fade is a fitness limit or a pacing mistake, going through 200 too fast and paying for it at 300. Those look almost identical on film. Telling them apart means knowing the actual split times the athlete ran, which the camera does not record.
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Related
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