This looks fun -Compatible with the Adidas Barricade 7.0 football boot, where it clips in the heel, but for tennis you clip it on your laces, the miCoach Speed_Cell employs accelerometric technology to capture all 360 degrees of a player’s movement on-court.

Just sync up with a smartphone, tablet, or computer after a match or practice, and you’ll be able to access up to seven hours of footwork data—from the total distance you covered to the speed of your fastest sprint. What’s more, the Speed_Cell integrates with Adidas’ miCoach training system, which allows you to track your progress as it leads you through a number of tennis-specific fitness drills.This Adidas miCoach is a free download app for any smartphones.

I would like to strap this on some of the players here in Los Gigantes, to see if it even registers any movement.

Only 70 pounds and you can buy it online from the Adidas web site, click the tenniszoo link