Top speed graphics tell you almost nothing worth knowing

Broadcasters have made a habit of flashing a maximum velocity on screen, a number with no context attached to it whatsoever.

A forward chases a long ball, does not reach it, and the broadcast rewards him with a number. Thirty-five point four kilometres per hour. There is a small graphic, the commentator says something admiring, and we move on.

What did we learn? Almost nothing.

A top speed figure is a single sample from ninety minutes. It tells you the fastest instant, not how often the player reaches anything close to it, not whether he can do it in the eightieth minute as well as the tenth, and not whether reaching it served any purpose. The winger who hit that number chasing a lost cause is presented identically to the one who hit it arriving in the box at the end of a fifty-metre run that produced a goal. The graphic cannot tell them apart because it has thrown away everything except the maximum.

There is a measurement problem underneath the editorial one. Peak values are the least stable output of any tracking system, because a single noisy frame produces a spike and the smoothing that would remove it also shaves genuine peaks. Different providers therefore report different maxima for the same sprint, which is why you occasionally see two numbers for the same player in the same week and neither broadcaster explains the discrepancy.

The number I would put on screen instead is repeated high-speed efforts, split by half. How many times did this player go above his own threshold, and did the second-half count hold up? That is a story. It has a shape, it changes during the match, and it lets a viewer see a full back visibly running out of legs in real time rather than being told after the fact that he covered eleven kilometres.

I understand why the peak wins. It is one number, it is big, it fits in a corner of the screen and it needs no explanation. Every good broadcast decision has to survive the eight seconds before the ball comes back into play, and context takes longer than that.

But sports coverage has already trained audiences to read a shot map and an expected goals figure, which are far less intuitive.

Give people something that moves. They will follow it.