It was with huge reluctance that I gave up my gym membership in July, despite losing 2st within the past year. I'm in no hurry to return to my formerly lardy proportions, but the pounds that I'm most worried about losing now are the financial rather than the physical kind.

I'm clearly not alone. About 54,000 fewer people took out gym memberships last year than they had 18 months previously, according to the accountancy firm Deloitte. It's a trend that's likely to snowball in these credit-crunched times. For my part, add the £79 fee to the £60 in petrol, not to mention the two coffees I was having a week, and the gym was costing £160 a month. And that's without counting the time I was spending on the ten miles of congested motorway to get there three times a week. As lovely as it was luxuriating in the female-only sauna and super jet-powered Jacuzzi bath, the prospect of saving £1,920 a year was too good to pass up.

So having cancelled my direct debit and thrown off the shackles of the cross-trainer, I ventured into the brave new world of keeping fit free of charge. I'm enjoying it more than I expected. The only limit is your imagination. Here are some ideas to get you started.

Walking

Head for your local park, common or woods and walk for an hour three times a week, tackling as many slopes and hills as you can. Aside from the toning benefits, walking also boosts your spirits, releasing increasing amounts of happy chemicals called endorphins as you speed up, according to the Depression Alliance. If you'd like some company, join a group. www.ramblers.org.uk, www.walkit.com

Calories burnt per hour: 266

Cycling

Fresh air, birdsong, trees and grass versus a sweaty Spinning class. No contest. Dust off your bike and get it serviced for £32 or buy a second-hand one for about £65. Invest another £120 in a helmet, lights, padded gloves and a fluorescent vest and you're ready to go. Cycling uses the big muscle groups in the legs and raises your heart rate. See www.whycycle.co.uk, www.bicyclesource.com

Calories burnt per hour: 566

Cleaning

You've saved an extra £200 a month (the nationwide franchise Molly Maid charges £50 a week on average) by losing your cleaner. But a light spray of Mr Muscle isn't going to cut it. Dusting those hard-to-reach places will give you a good stretch, while polishing furniture with wax rather than spray is great for toning upper arms. The satisfaction of looking around your sparkling home and knowing it's the result of your labours is unbeatable.

Calories burnt per hour: 160, hoovering at a moderate pace

Swimming

My local baths charge £2.45 for an adult swim. It's not up there with my old club's 25m infinity pool, but you can still reap all cardiovascular, endurance-building benefits of swimming. www. britishswimming.org, www.artofswimming.com

Calories burnt per hour: 560, doing the front crawl at a moderate pace

Sex

Few workouts can beat sex for an all-round health boost. It also strengthens your immune system, combats stress and improves your mood by producing endorphins. And the release of the intimacy-enhancing hormone oxytocin acts as a painkiller and is linked to better sleep and even reduced rates of cancer. For inspiration, take Orgasm (Hamlyn, £12.99) by the sex therapist and author Nicci Talbot to bed.

Calories burnt per hour: up to 408

Voluntary work

Sick of all the litter blighting your park? Well, stop moaning and do something about it. Limber up with some bending, stretching and conservation work. Bask in the rosy glow of having done something worthwhile for your community while erasing unwanted inches. www.voluntaryworker.co.uk

Calories burnt per hour: 400, while digging

Inline skating

You'll need to invest £50 in a good pair of skates, but these should last for years. Toning your hamstrings, bottom, thighs and hips more effectively than cycling, skating is also a nifty way of getting around.www.tryskating.com, www.londonskaters.com.

Calories burnt per hour: 875 at high speed

Exercise at home

Dig out those old exercise DVDs or hit your local HMV, charity shop or library and transform your front room into a personal studio. And should you develop a dislike of your “personal trainer”, there's always the eject button.

Calories burnt per hour: 175 for a gentle yoga session; 490 during high-impact aerobics

Gardening

All that pruning, cutting back and digging is great for strengthening muscles and then there are the feel-good benefits of being outdoors. You could save about £40 to £80 a month in gardening costs. There are plenty of tips in Garden Your Way to Health and Fitness, by Bunny Guinness and Jacqueline Knox

(Timber Press, £14.99).

Calories burnt per hour: 500 for mowing the lawn; 300 for weeding

Team up with a friend

If it's good enough for Madonna and Gwyneth Paltrow... Research shows that you are more likely to stay motivated if you pair up with a friend to get fit. It adds a sociable and sometimes enjoyably competitive element to exercise. You'll wonder why you ever needed that £160-a-month personal trainer.

Free health club

Being deskbound isn't a reason to neglect your fitness regimen. The Times Health Club is free and is full of nutrition and fitness tips, as well as great tools to track your progress and keep you motivated. I'm logging on in a minute - after that last HobNob.

timesonline.co.uk/healthclub

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