football skills, football training, football player

Being able to throw the ball large distances from the touchline confers an obvious advantage in football, especially if the ball can be propelled into the region of the opponents’ goal area. But while some football players are renowned for having long throw-ins, what does the science say about maximising thrown-in distance generally? A team of British scientists has been trying to answer exactly this question by studying maximum-effort throws using videography.

In the study, a male football player performed maximum-effort throws using release angles of between 10 and 60 degrees (the initial inclination of the path of the ball as it is released from the hands). These throws were then analysed using two-dimensional videography and the player’s optimum release angle was calculated by substituting mathematical expressions for the measured relationships between release speed, release height and release angle into the equations for the flight of a spherical projectile.

The result indicated that the musculoskeletal structure of the thrower’s body has a strong influence on the optimum release angle. In the study, using low release angles helped the player to release the ball with a greater release speed; because the range of a projectile is strongly dependent on the release speed, this bias toward low release angles reduced the optimum release angle from 45 degrees (the mathematical theoretically optimum angle for projectiles generally) to about 30 degrees. Calculations showed that the distance of a throw may be increased a few metres further by launching the ball with a fast backspin, but when backspin is applied, the ball must be launched at a slightly lower release angle than 30 degrees!

Sports Biomech 2006 Jul; 5(2):243-60