Exercise should be its own reward. In an ideal world, you would spend hours in the gym and a grateful body would show its thanks. As everyone who has ever felt the pain of the cross trainer knows, it doesn’t always work like that. Lifting the huge weight of resolution is no problem. Sticking with the programme is what’s difficult — so difficult that almost nine out of 10 gym-joiners become ex-gym-goers within 12 weeks.

The solution, they say, is to keep track of your progress. At its best, the internet is a wonderfully interactive tool. More flexible than a yoga teacher, it should easily be able to offer a personalised programme, with special software translating your sweaty progress into a chart.

Most fitness sites, however, don’t make it this far. Like a lazy slob who never gets off the sofa, they flex a tiny fraction of the internet’s muscles. The celebrity trainer Josh Salzmann’s site (www.truthaboutfitness.com) has clips of Kenneth Branagh and the Duchess of York saying how wonderful he is, but proves purely a vehicle to sell his DVD. Joanna Hall (joannahallonline.com) provides a bit more information, but not much; and even the London Marathon site (www.london-marathon.co.uk) doesn’t do interactive.

A site called www.myfitnesspage.com looked far more promising, admitting that a lack of measurable results is the primary reason people give up and offering interactive charts that promise to personalise your exercise regime. When tested, however, these functions didn’t always work, and my query e-mails went unanswered.

Still, what’s great about going online is that, sooner or later, you will find someone who has written software that will help keep you on the exercise wagon. Jean Gareau, a Canadian from Montreal, is a keen cyclist who wanted to see how all that pedalling looked on a graph.

“I was training for an event and I wanted to know how many hours I had done in the past six months,” he says. “I wanted to have that information fast, showing distance, speed and average heart rate, and there was absolutely nothing out there.” So, Gareau, a director of engineering at the software manufacturer Widcomm, spent his nights and weekends writing a program himself. He then put it online at www.mysporttraining.com, where so many people found it and bought it that, after five years, he gave up his day job to run the company full time.

Having started with software for a Pocket PC, Gareau has built a family of products that include applications for Palm OS and Windows. Although it comes with a 74-page manual, the Windows version of MySportTraining is a doddle to use. You choose an activity from a list, add as many details as you want — distance, heart rate, perceived effort — and add it to your calendar. Put in enough workouts and you reach the fun bit, which is seeing all your hard work on a graph.

Gareau’s payment model does not include charging for updates: paying just £22 for the Windows version of his program entitles you to as many upgrades as he can write (in five years, there have been 77). Unfortunately for him, it means he can’t make more money from existing customers, but £22 for life makes it a bargain for cyber-fitness fans.

Getfit.com, which I found through www.gymuser.org.uk, is altogether different. Working on a subscription basis (£6.25 a month), this is a good- looking site that will create a fitness programme for you. Enter your goals, current fitness level, schedule and access (if any) to fitness equipment, and its artificially intelligent brain decides which workout you should be doing. Even if you don’t have access to so much as a dumbbell, it will devise a personalised routine for you.

Getfit also has a more advanced option for people who belong to a gym and have their own regime already. However, getting it up and running is harder work than lifting a rhino on the bench press. The instructions are nothing like as clearly written as on Gareau’s site, the system is much less intuitive, and in many respects it does not get so personal. Unlike MySportTraining, you cannot, for instance, enter details within the main fitness programme about how many calories your regime burnt off or what interval training you did.

Steve Russell, one of the owners of Getfit, says that only one in 10 customers use this part of the software. “Ninety per cent of people don’t belong to a gym or know anything about fitness, and most want a programme created for them.” Once you have set up your programme on Getfit, it is simple to use, and there are some neat features — in an exercise library, you click on a figure of a male or female body, choose the muscle groups you want to train and select from a list of options. Each takes you to a picture of the exercise, a description and a short video showing it in action.

Neither of these websites will, of course, do the workout for you. To keep fit, you will still have to get hot and sweaty at least three times a week. On the other hand, because you can personalise your regime, measure your results and chart your progress, they might just make all the difference between getting fit and giving up.

WEB’S THE PLACE FOR A WORKOUT

www.getfit.com

There is a video tour for newcomers, but no free trial period — Steve Russell says they’ve spent enough setting it up. Once you sign up, your account will be debited automatically every month, unless you cancel immediately. At £75 per annum, this is quite an expensive add-on to a gym membership, but Getfit is appealing, especially if you want a tailor-made programme. For £30 a month, you can also consult an online fitness coach.

www.mysporttraining.com

A one-off fee of £22, which includes a stream of updates, represents a terrific bargain (there is a free two-week trial, too). Even if you don’t find the software perfect to start with, it is likely to improve with each update, as Jean Gareau listens to his customers — so it is worth persevering. Other options include My Running Log, Pace Calculator and the regime Gareau has discovered people want most of all, My Personal Diet.

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