Recently one of our partner teams in the Women’s Super League was wearing an upper body GPS-sensor and our N11 sensor at the leg in a league match. The results confirmed what we have observed many times before: Sprint distance is an inadequate indicator of load.
The reason is as simple as it is obvious: footballers make a lot of high intensity accelerations and decelerations that are not linear sprints but still generate a lot of load. It could be short runs with fast change of direction, it could be explosive actions such as jumps, turns and finishes.
Just 13 meters of sprint – yet highest load.
As the diagram shows, the winger has by far the longest sprinting distance over 90 minutes. It’s not surprising, as wingers have more space to run over longer distances and reach sprinting speeds above 25 km/h. However, the player with the highest load is a defensive midfielder who only completed 13 meters of sprints.
But she spent 450 seconds engaged in high-intensity accelerations and decelerations in smaller areas mostly at speeds below 25 km/h. In comparison, the winger spent 309seconds on high-intensity accels and decels – mostly on longer linear runs. So, when discussing mechanical player load, sprinting distance is merely the tip of the iceberg.
Are midfielders getting the right training?
Football tracking favors linear sprint meters over accelerations and decelerations below 25 km/h simply because that what a GPS satellite can track better. Today, players who have few sprint meters logged are asked to do extra sprints after practice. The very same players that worked the hardest of all. Our data shows that there is no correlation between sprint meters and player load. Let me know if you want to know more about the load metrics in the N11 system, developed in partnership with SoccerFitness.