The veteran Sunderland striker is defying the ageing process by going back to the Ice Age? —? or, to give it its technical name, the cryotherapy chamber. THE?January transfer window is now slammed shut and Premier League clubs have done their business for the?2016-17 season. I have a better understanding of my body thanks to all the sports science and I know when I need to have a rest day and when I need to work hard. most read in footballdiamonds are foreverChelsea's new Nike kit leaked online. As I put on the slippers, gloves and face mask necessary before going in, steam billowed out of the side of the PolarFit chamber at the Cottagers training ground in Motspur Park. Boss Gareth Southgate is worried about the injury-plagued stars ability to play two games in a week. Getty Images4Antoine Griezmann has been the subject of interest from a number of clubs this termMOST READ IN SPORTdiamonds are foreverChelsea's new Nike kit leaked online. Getty Images4Wojciech Szczesny has been in tremendous form during his two-year loan at Roma and retu. Jose Mourinho wants to bring in a huge name in the summer as he tries to bring the Red Devils back among the elite of world football. ansfer blogSouthgate overlooked the Arsenal midfielder for the recent games with Germany and Lithuania but remains a massive fan of the player.