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Ground-breaking research using miniaturised global positioning system technology is helping to find ways of cutting injury rates among elite Australian footballers.
GPS devices strapped to players' backs have shown they move faster than their predecessors did decades ago, researchers say.
The size of the players had also increased in the same period, Professor Kevin Norton of sports educational institution Sports Knowledge Australia said. This made player injuries more severe, particularly after collisions, leading to worsening health problems in later life, he said.
Professor Norton said GPS devices around the size of a small cellphone were encased in padded sacks on the upper backs of AFL, rugby and soccer players while 24 satellites measured their exact position.
Some of the devices also measured acceleration and deceleration rates.
"There is incredible acceleration and g-forces involved in all rugby and soccer and football codes, and we haven't been able to measure those before because you cannot measure those things on an athlete in a laboratory," Professor Norton said.
Over several years, Professor Norton and his colleagues have found AFL players have become more powerful runners over shorter distances.
Soccer is played at a higher speed and with fewer stoppages, and the rugby codes have also become faster.
Training now needed to be targeted to mimic the actions players needed to perform during games and, in some cases, the rules also needed to be changed to slow them down.
"It reinforces to us the link between slowing the game down ... and reducing the chance of acute injuries during that game, particularly high speed collision injuries," he said.
Professor Norton said retired AFL players have 80 times the rate of hip and knee replacements than in non-players of the same age.
The Black Sticks used a similar system in the buildup to the Melbourne Commonwealth Games to record their movements and heart-rate during a match. The average hockey player runs 7km in a 70-minute game - some Black Sticks run 9km.
- AAP
