At Decathlon, we already have lots of data on how a shoe behaves when walking, but little on the movement of the foot during a golf swing. This is why we called on the Sportslab teams, a team of experts dedicated to understanding motion during sport.

With Sportslab's engineers, we defined the study to be conducted in order to specify, firstly, the pressure zones by level of intensity and, secondly, the direction of these forces during a golf swing, for the left foot and the right foot.

We brought in eight golfers between 2 and 29 handicap. Six men, two women. They each hit eight balls with their 7-iron and eight balls with their driver. They were all wearing their own shoes: Inesis Grip Waterproof.

The data recording equipment was as follows:

High-speed cameras captured the slightest movement of the shoes, up to 1000 images per second.

• Two force plates were used to detect the forces applied to the ground in three dimensions
• A measuring sole placed under the sockliner was used to record pressure points

128 swings later, we sent all the data to the machine and analysed it.

During the backswing, weight is distributed 60% on the inside of the back foot. At the moment of impact, the player's weight shifts to be mostly on the front foot, with up to 80% more pressure than body weight. The forces are greater using a driver than a 7-iron.

The results highlight the complexity of a golf swing, how the forces, kinematics and pressures exerted by both feet vary widely during the swing, and the multi-directional stresses. They also differ greatly between the front and back foot.

We will be able to use this highly detailed data to make our design choices by superimposing the demands of walking onto those of a golf swing. The technical solutions to meet the needs of traction, durability and flexibility are at odds, hence the need for fine-grained data to find a happy medium for design choices such as the positioning of the spikes, their orientation, density, etc.