JAMIE’S PERFORMANCE COULD BE BOOSTED BY 7 PER CENT, SAYS EXPERT

ROGER PIELKE, director of the sport governance centre at the University of Colorado, says of Jamie Vardy’s combination of substances: ‘Both nicotine and caffeine are among the more well-studied performance-enhancing substances. It gives you a little energy boost. ‘There’s a study in my new book about caffeine across a range of sports and the performance enhancement is three to seven per cent, whether that’s rowing, sprinting or whatever. ‘Anyone who wakes up in the morning and has a cup of coffee or tea knows the performanceenhancing effects of caffeine. They’re perfectly legal and athletes take them, which is no surprise. Used together, do they give you an added boost in terms of energy? I’m not aware of any studies which have looked at the double benefit but look at Maria Sharapova with her 30 medicines — athletes are going to take everything and anything they can that might give them a benefit, regardless of whether the science is there.’ But Mark Leather, head of sports performance at Bolton Wanderers, played down the effects. He said: ‘Snus is a fad that I’ve seen used by a few players in the last two or three years. Some take it for its relaxing effect, instead of smoking, and it’s a fashionable thing to do. I don’t know why they do it and I wouldn’t advise players to, because of the risk of cancer. ‘I’d be very surprised if players used it during a game — it would be an irritant in your mouth. They might use it when they come o off the pitch to relax. And pl players in every changing roo room will drink Red Bull befo before a game to give them a little pick-me-up, but I don’t think it would have a combination effectweffect with the nicotine.’