WHO, WHAT, WHY?
The Magazine answers...
Boxer Ricky Hatton sheds up to 40lb to get in shape for each fight. As he prepares for Saturday's world title bout with Floyd Mayweather, how does he do it?
"They've nicknamed me Ricky Fatton. Mind you, I have had a lot on me plate lately."
Hatton makes a joke out of the way he famously balloons in weight between fights. A photograph (above) of him and Bernard Manning lying on a settee in their underpants hangs in his Manchester gym.
Guinness, fry-ups and fast food are not usually wolfed down by world-class sportsmen.
"It couldn't be more horrific what he eats," says the man in charge of Hatton's diet, Kerry Kayes, speaking from Las Vegas.
"Anything that's bad, greasy, take-away or pies, he washes down with 12 to 15 pints of Guinness and Bailey chasers. He couldn't do it any worse.
Four or five meal replacement supplements a day
Three or four small meals: chicken, pasta, rice, fruit
Capsules boost fruit and veg intake and provide Omega oils
Pre and post-workout energy drinks
Intense fitness and strength work
"His mum and dad can't talk him out of it and his girlfriend Jennifer can't, so what chance have I?"
Former bodybuilder Kayes does not know the size of his task - literally - until Hatton walks into the gym on the first day of training before each big bout.
"He's usually about 40lbs overweight and it's quite a hard scenario to get his weight down and increase his nutrition to cope with the workload we put on his body, because every time he trains we need to overload his body and send a signal to it that it needs to be fitter and stronger.
"To do that it needs to repair itself from the trauma, so we need a lot of nutrients but we can't afford calories."
Two-thirds of Hatton's intake comes from meal replacement supplements and one-third from food.
The powder supplements, of which he has four or five a day, provide 42g of protein and 270 calories. A normal meal providing that amount of protein would usually contain about 800 calories, says Kayes.
Hatton's food intake comes from what Kayes describes as "clean" sources of carbohydrate such as rice and pasta, and protein-rich foods like chicken.
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The government recommends five fruit and vegetable portions a day, but Hatton has the equivalent of 15, provided by capsules and the real thing. In total, he consumes 3,500-4,000 calories a day.
On the morning of a fight Hatton used to have the Mega Fry-up at the Butty Box in Manchester but there will be no repeat in Las Vegas.
Kayes says the yo-yo weight loss and gain is damaging Hatton physically but thinks his lifestyle probably helps him relax between fights.
"It's bad for his body but good for his mind. The kid's under enormous pressure and Billy Graham [his coach] doesn't want him to box much above 30 anyway."
Up and down
In the short-term it's not clear what the risks are, says Simon Langley-Evans, a professor of human nutrition, but there are problems long-term.
"Ricky Hatton is a very fit individual and he's reasonably healthy. But when people gain and lose weight, or 'yo-yo diet', they gain weight more easily as they get older. Every time he goes through the cycle, he will probably gain more weight.
"This kind of yo-yo dieting produces the worst outcome in cardiovascular risk in middle age. It's almost better to be someone heavier and not trying to lose weight, rather than losing weight and putting it back on again."
WHO, WHAT, WHY?
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It's unclear why but going up and down in weight increases fat deposits in the abdomen area, which increases the risk of heart disease.
Many people do this all the time but it's a futile activity, says the professor, because the weight goes back on again unless they increase their physical activity.
Meal replacements can be useful, says Richard Chessor, performance nutritionist at the English Institute of Sport, but the overall diet must remain nutritionally balanced.
And unless people have a "negative energy deficit" like Hatton - burning more calories than they consume - then forgoing a 100-calorie bag of crisp for a 200-calorie shake is not going to help them lose weight.