Brian O'Driscoll takes on 'Death Zone' training session with England 7s squad

Having retired in 2014, rugby fans are now more accustomed to seeing Brian O'Driscoll behind the camera or on the microphone dishing out his views and expert analysis. However, recently he laced up his boots as he joined the England Sevens Squad at one of their infamous 'Death Zone' training sessions. With the HSBC Sevens World Series beginning this weekend O'Driscoll, who is an ambassador with HSBC, went out to join the England side in the truly gruelling session, whose name comes from rock climbers describing the altitude at which there is not enough oxygen for humans to breath.  In the su…