Rugby union's Six-Nation tournament kicked-off on Friday but in Wales, research has been taking place into the affects of concussion on players which is causing increasing concern.

Professor Damian Bailey and his team have analysed 280 current and retired players, applying pressure on the brain in controlled laboratory conditions and investigating such areas as the early onset of dementia. 

Al Jazeera's Lee Wellings reports from Cardiff

Source: Al Jazeera