Block setup wrong
Front block too close or back block too far flattens the drive angle. Standard setup: front pedal 2 foot-lengths from the line, back pedal 3. Adjust to comfort within that range.
Slow block starts are almost never about reaction time. They are about setup. Out of seven athletes who say they are slow out of the blocks, six have a setup or set-position problem that shows up on the first stride. The other one needs to lift more. Below: the diagnosis tree, the fix per cause, and how to verify the fix on video.
Front block too close or back block too far flattens the drive angle. Standard setup: front pedal 2 foot-lengths from the line, back pedal 3. Adjust to comfort within that range.
Hips set above shoulders rotates you up too early. Hips set below means no horizontal force. Standard: hips slightly above shoulders, ~10 degrees, weight forward over the line.
Eyes up at the gun rotates the whole body up. The fix: pick a spot 1-2m in front of the line and keep eyes there through the first 3 strides.
Block starts are the easiest sprint phase to film: side-on, 15-20 feet away, capture the set position through stride 5. Upload it and AI tells you which of the seven causes is the actual problem in your start, plus the drill that fixes it.
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Run through these checks in order. The first fail is usually the real problem.
Front pedal 2 foot-lengths from the line, back pedal 3. If you can't push hard against either, the spacing is wrong.
Hips slightly above shoulders. Weight forward over the line. Head neutral, eyes 1-2m down the track.
First push is against the back block, not a step out. If your first move is your front foot lifting, you are skipping a push.
Eyes stay down through stride 3. Pulling the head up rotates the body up and kills the drive angle.
Foot lands behind the hips, not ahead. Overstride here means the rest of the drive is fighting a brake.
Film a fresh start with the corrections. The change should be visible by stride 4.
Common questions athletes and coaches ask about this topic.
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