The four DJs show off the impressive results in a series of 'before' and 'after' shots in the new edition of the magazine.
Yates, who added 4cm of muscle on to his chest and arms, commented: "My first reaction on seeing the 'after' photos was that it wasn't real. It looked like I'd nicked somebody else's body and stuck my head on it. It felt like I had, too. Six weeks before, the only exercise I'd ever done was a bit of running and the odd press-up. Now I was in Men's Health cover-model shape."
While admitting that the training regime "wasn't easy'," the Radio1 star added: "Knowing you're
actively bettering yourself is a great feeling. A cover model body is one hell of a bonus."
Yates's colleague Greg James also showed off a 3.5cm chest muscle increase following his "relentless and tough" six-week challenge.
Reflecting on the changes, James commented: "It's too much to say the last six weeks have changed my life. But they have changed my lifestyle. I am now the guy who wants to go to the gym every morning. That, for me, is much more than I thought I'd ever achieve."
Richard Bacon, who lost 5.5kg of weight during the six weeks, admitted that having the effects noticed by other people was encouraging.
"I was pleased with my results. But it's other people noticing that makes you feel you're getting somewhere," Bacon said. "Russell Brand came on the show and noticed straight away, saying 'You've been going to the gym a lot, haven't you?'. And I had. All those hours with Al made one thing obvious: the promise on the cover is accurate. You can change your physique in just six weeks."
Finally, Absolute Radio's Ben Jones confessed that he thought "a million things" stood between himself and achieving a six-pack.
"Getting leaner makes you look and feel amazing," he concluded. "You're used to having jam on toast for breakfast, instead I'd be rubbing Cajun spices into springbok or ostrich.
The full results and stories can be seen in the July issue of Men's Health, on sale from today.
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