Sensor or protection?

[ToniAllende]

Rugby Championship In the past I could see some players from other teams, had some kind of protection in the back of the shirt, more specifically on the top, the number, I attached a picture for you to see, anyone know to use it ...


Sorry for my bad English...


https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-ash4/486903_531285890231295_1950219498_n.jpg

TKZ

 

[TRF_Olyy]

I think they're GPS recievers/transmitters/whatever they're called.
The sports scientists use them to track how far/fast the players run throughout the game.
It helps them see how much work they get through, and then they can tailor their recovery/training around that information.

 

[ToniAllende]

Thank you very much, but equally I would like to know more deeply, to see if anyone knows it.

 

[smartcooky]

Thank you very much, but equally I would like to know more deeply, to see if anyone knows it.

Here's one under the jersey

 

[ToniAllende]

Tkz very much