What is it about men? One minute they're eyeing their tubby waistline in the mirror, the next they're fit and flab-free. How do they manage to shed the kilos so fast? We find out. Time to man up … and nick their tactics.
Be sceptical
You won't catch many guys banging on about the latest faddy diet. Men like facts. They know that no matter how many dawn-harvested goji berries they nibble, their beer bellies won't magically metamorphose into ripped abs while they're sitting down watching Gossip Girl.
They don't waste time with suspect hype. They know that if they want to lose weight and feel great they need to exercise more and eat less rubbish. Might just work, huh?
But don't be a hater
You're also unlikely to catch them weeping about how hideous they look, how they're too fat for their skinny jeans or too visually disgusting to leave the house. Guys seem to know instinctively talk like that batters your self-esteem and might even keep you from reaching your fitness goals.
"That kind of self-sabotage will keep you from getting what you want you'll live a self-fulfilling prophecy," says JoLynn Braley from The Fit Shack. The good news: research shows individuals who exercise are 60 percent more likely to feel better about their bodies.
Keep it simple
Whether it's sex, sports or slimming, guys have a one-track mind. This sometimes exasperating tendency of theirs is a big weapon in their fitness attack: they stick to the plan, whether it's skipping the takeaways or jogging home twice a week. It's simple but undeniably effective.
Meanwhile, we wonderfully multitasking ladies like to make things a bit more complicated. We draw up long lists of banned foods, weigh out portions, spend entire evenings preparing low-kilojoule lunchboxes, get out of bed at 5am for boot camp … And hit the wall exhausted and dispirited by day three.
We need to give ourselves a break. Experts say start with your worst habit (TimTam tea breaks?) and one fun fitness goal (Zumba classes anyone?) and take it from there.
Put food in its place
Most men don't see food as a reward; it's what they cram in their gobs when they're hungry. It is fuel for the magnificently powerful machines that are their bodies. This is another bit of genius we should nick because when you see food as fuel, you want to it be as effective as possible.
Healthy, protein and wholegrain-packed food makes our bodies perform best and keeps us full for longer. Include plenty of iron-rich foods such as lean meat, beans, lentils, beetroot and spinach for extra energy too.
"Iron deficiency can make you feel sluggish by decreasing your ability to carry energy-essential oxygen," says diet and fitness guru Dr Melina Jampolis. Ditch the "If I vacuum the house, do the shopping, finish this report, I can have that double-choc cupcake" way of thinking. Trust us, your hot new bod will be a more exciting reward.
Quit the guilts
But, that said, we know the lure of the double-choc cupcake is strong. It's yummy and life is short. So don't spoil your butter-frosted enjoyment with the guilts. It's just a cupcake; it's not an overwhelming failure. It's no reason to give up. Men know the odd pothole in the road is just that. It is not the end of the road for your brilliant feel-great plan.
"Why beat yourself up about a diet slip-up?" asks fitness expert Tony Horton. "It doesn't erase all the hard work you've accomplished up until now, or mean that you have to start over. Just pick up where you left off and move on."
Take a leap
Men are all about the action. They decide they are going to make some changes. Then make them. They don't need it to be the first day of the month to go for a jog. They don't need new gear. They'll sprint off in one of your old T-shirts and the mouldy pair of runners they last wore trying out for their high school football team.
They don't need to agonise over whether Body Pump class will be 100 percent compatible to their new fitness regime, they just turn up for it. They know sooner you start, the sooner you'll get results.
Pull your weight
When they want to change the way their body looks and feels, guys sprint straight to the dumbbells. Which, according the experts, is anything but a dumb move. Weight training, which less than 20 percent of us ladies do, doesn't just give us that super-sexy definition we're all mad for: it's also one of the most effective ways to rev metabolism, improve bone density and blast fat.
"Women often choose light weights that they think will magically shape and tone the muscles, whereas men will go right for the big bang," says Alwyn Cosgrove co-author of The New Rules of Lifting for Women.
The right lift? "Pick a weight that you can definitely lift eight, maybe 10, but not 12 times," he says. "Then work up to three reps of 10."