A woman shopping in the sales(Rex Features)

"If you're serious about losing weight, you need to find a way to do it that's enjoyable," says personal fitness trainer Ray Klerck, (www.rayklerck.com.) "Once you've found an activity that gets you pumped with excitement, losing weight will be as easy as, er, pie."

Spend some money

If you got some shopping vouchers for Christmas, now is the time to spend them. Because after an hour of shopping, it's not just your wallet that'll feel lighter, your body will too! In fact, you'll burn 184 calories in sixty minutes*.

"When out shopping, you're either standing or walking the entire time," says Klerck. "So although it's not aerobic exercise, you'll still work off a decent number of calories. If you're carrying some heavy shopping bags, then you'll also be getting some lifting exercise too."