Shrill squeals of squeaking sneakers marked the sudden stops and starts of Andy Murray and David Ferrer during Sunday’s Shanghai final and served as a sonic reminder of Stefan Edberg’s adage that “tennis is a game of legs.â€
Movement is so essential to upward mobility in the ATP rankings it’s hardly surprising the world’s top five players—Novak Djokovic, Rafael Nadal, Murray, Roger Federer and Ferrer—are all known for quick court coverage and finely-tuned footwork.
Coaches and racquet customizers’ commonly video tape players’ swings to provide stroke analysis and remodel racquets to suit players’ swing paths, but can technology aid foot health and footwork?
One coach is using sensor technology embedded inside tennis shoes and corresponding video analysis of a player’s movements on court to gain a better understanding of how the feet perform during play. Dr. Allan Grossman, a USPTA coach and podiatrist specializing in treating tennis players at the Harrisburg Foot and Ankle Center in Harrisburg, PA, embeds a sheet fitted with thousands of sensors that pinpoint pressure points inside tennis shoes. The battery-powered device connects to a cuff wrapped around the athlete’s ankle to measure pressures on the feet during activity and transmit the data, using Wi-Fi, to a laptop computer, where both doctor and athlete can see exactly where pressure points arise during on-court movement.
His findings have been surprising.
‘Conventional thinking is that when tennis players load on the back leg to hit a forehand or plant the foot to change direction that their weight puts pressure on the outside of the foot,’ Grossman says. ‘What we learned through thousands of scans of players of all different levels is that in virtually every case the most pressure is applied on the inside of the foot. That’s quite surprising—it’s the opposite of conventional thinking.’
This video illustrates the point. Notice when the player plants his right foot to push off—the pressure points (represented by red and orange colors on the shoe images) are most intense on the inside rather than the outside of the foot:
