RANDY Salim, manager of business development at the Economist Intelligence Unit, had thought himself reasonably fit before embarking on the MacLehose Trailwalker race. His knees have never been the same since. Todd Benoliel, product manager at Quaker Chemical, thought the same. Almost a year later, his hip still has not healed. Although one jogged regularly and the other played rugby, neither Mr Salim nor Mr Benoliel trained for the 100 km race, and both have suffered as a result. According to physiotherapist Helen Cooper, proper training for the nine-peak race across the MacLehose Trail is a must. ''A lot of people go in with their eyes closed,'' she said. ''It's a big marathon. An ordinary marathon is a piece of cake compared to it.'' Pulled achilles tendons, sore knees, sprained ankles and blue toes are among the injuries found on the blistered-feet brigade emerging from the race. One of the most common misconceptions is that if already active and reasonably fit, most people should be able to walk the trail in the 48 hours or under required to qualify as having successfully completed the race. ''If you are golf fit, you are not necessarily MacLehose fit,'' said Ms Cooper. Even running works different muscles than those used for walking up and down hills. For those out of shape, Ms Cooper suggests training should begin at least six months in advance, so if you have not already started your programme you had better wait until next year. Walking in Hong Kong's country parks and along the MacLehose Trail at weekends is considered by most experts the most important element of training for the race, which usually takes more than 24 hours. At least two to three days of training during the week and a long hike at the weekends is a good foundation. The organisers also suggest participants should climb the peaks on each of the nine stages of the MacLehose Trail. These may be timed, which will help in preparing psychologically for the race. They also say those sections which will probably be walked at night should be practised both by day and in the dark. In addition to power-walking and long-distance hikes at the weekends, Ms Cooper suggests stretching, swimming, walking up and down steps, and even light weights. The level of training should increase gradually to avoid unnecessary strains. ''One thing they must not do is go out and walk 50 km in a day,'' said race co-ordinator Major Sean Dexter. ''Start off with shorter distances and build up.'' By the end of the training period, each team intending to walk the trail should be able to complete a 10 to 11-hour walk with ease. Two weeks before the event, participants should take a two-day walk of 8-10 hours each day. Care is also advised in other aspects of training during the week. Overdoing gym training, for example, can lead to muscle strain. ''People love [step machines],'' said Ms Cooper. ''The pedal is not necessarily in a good position for your hip. You would do better to run up and down the steps of Jardine House.'' Ms Cooper is already receiving visits from patients who have mistrained for the race. Experts suggest no one schedule will produce a particular time or guarantee an injury-free walk. The level of fitness among the Gurkhas, for example, is for the most part better than that of the average competitor. Their record time is a little more than13 hours, as opposed to an estimated average of 30 hours of walking for civilians. ''The Gurkhas undoubtedly have a natural fitness. They train particularly hard. They put in longer training sessions than civilians are prepared to do,'' said Major Dexter. But civilians vary in strength and disposition as well. Avid sportsmen and former marathon runners such as Jardine Securicor services manager Jonathan Tedd finished the walk in less than 22 hours, but his training schedule was not typical of civilians. Two to three times a week he walked the hills of Lantau, and at weekends walked a four to five-hour hike. A good team and decent training no doubt assisted him, but his marathon experience and athletic dexterity also helped in the jogging of the final 20km. A couple of pairs of good cotton socks and Vaseline on the feet, breasts, arm pits and crotch are advised for long walks and, said Ms Cooper, ''don't wear hiking boots above the ankle unless you are used to it. It will really mess up your knees''. Proper diet is equally as important. Most athletes are aware that a diet high in carbohydrates provides the type of energy needed in training, but carbohydrates should not be provided solely from bread. Nutritional therapist Louise Purvis points to rice, oats, rye, millet and grains such as buckwheat and spelt. Combined with the grains, pulses such as lentils provide a good source of nutrition. For energy on longer hikes, Ms Purvis advises against short-term energy sources such as chocolate or foods rich in sugar. Cashews, almonds and dried fruits are good snack foods. ''The more one trains, the more one needs to eat,'' she said, suggesting twice as many carbohydrates as any other food group, and lots of liquids.