Nobody watches the second step out of the blocks

The first stride gets all the coaching attention, but the race is usually lost on the one immediately after it.

Freeze any start sequence at the moment the rear foot lands. That is step one, and it is the step everyone has an opinion about: the shin angle, the arm split, the head staying down. Fine. Now advance two frames and look at what the front leg does when it comes back to the track.

That second contact is where starts go wrong, and almost nobody films it properly because the camera is usually set square to the blocks and the athlete has already left the useful part of the frame.

Here is what happens. The push out of the blocks is a long, generous contact against a fixed pedal, and it flatters everyone. The athlete gets a big impulse essentially for free because the pedal will not move. Step two has no pedal. It is a live contact on a compliant surface, and the athlete now has to reproduce a similar direction of force with a foot that is landing under a body which is still travelling forward faster than the leg can cycle. Most sprinters cannot. They land slightly ahead of themselves, the hips drop, the torso pops up to protect the position, and the whole beautiful forty-five degree line collapses into an upright running posture by step four.

You can see it without any equipment. If the athlete's back is a straight line at step one and a curve at step three, the second step ate the start.

The usual fix is wrong, in my view. Coaches respond by pushing the athlete lower for longer, drilling wall runs and resisted marches until the athlete is holding an angle their strength cannot support. That produces a start that looks correct in a still photograph and is slow, because the athlete is now reaching to stay down and every contact lands in front of the centre of mass. Braking, dressed as technique.

The better instruction is dull. Get the second foot down early and let the angle rise on its own. A start that unfolds over five steps instead of being held for eight will feel abrupt to the athlete and read as scruffy on video.

It will also be quicker to ten metres, which is the only opinion the clock has.

Film from the side, low, and start the clip at step two. You will stop arguing about the blocks within a week.