Why a brisk walk is a really great workout

This activity will melt away the pounds, tone your flabby bits and leave you on an emotional high. Yet the form of exercise destined to become the fitness trend of 2007 does not require gym membership or a personal trainer. All you need to do is walk.

"Walking is a refreshing alternative to complicated aerobic routines and overpriced gym memberships," says personal trainer Lucy Knight, author of a new book on the exercise.

"It is free, enjoyable and already a part of everyday life. All you need to do is correct your technique, walk faster and for longer and you will lose weight."

There is much evidence of the benefits of walking. Scientists at the University of Pittsburgh recently revealed that overweight people who walked briskly for 30 to 60 minutes a day lost weight even if they didn't change any other lifestyle habits.

Another American study found that people who walked for at least four hours a week gained less weight (an average nine pounds less) than couch potatoes as they got older. Last year, researchers at the University of Colorado found that regular walking helped to prevent peripheral artery disease (which impairs blood flow in the legs and causes leg pain in one-fifth of elderly people).

Walking can even prevent colds and more

Researchers at the University of Massachusetts medical school found that people who walked every day had 25 percent fewer colds than those who were sedentary.

Because walking is a weight-bearing exercise, it can also help prevent the bone disease osteoporosis.

"Bones are like muscles in the way that they get stronger and denser the more demands you place on them," Knight says. "The pull of a muscle against a bone, together with the force of gravity when you walk, will stress the bone -- which responds by stimulating tissue growth and renewal."

Best of all, walking makes you feel good about yourself. "For people suffering from depression, walking three to four times a week for 30 minutes has been shown to enhance their mood," says Knight.

Even if a 20 minute power walk at lunchtime is all you manage, after six weeks it could be comparable to a course of psychotherapy, psychologists at the University of Illinois found. Here's how to walk your way to weight loss and wellness:

How much, how often?

Health experts recommend that we should walk 10,000 steps a day (about five miles) to stay healthy, yet most Britons walk only 4,500 steps. You would probably need to tot up at least 16,000 steps a day to lose weight.

Knight suggests the following workout plans, depending on your level of fitness. With each, you should aim to progress by increasing the duration of your walk by five minutes every two weeks, and the intensity by walking faster. "In just three months, the results should speak for themselves," says Knight.

Beginners

Monday to Saturday: Walk ten minutes at a moderate pace.

Sunday: Walk slowly for 20 minutes.

Intermediates

Monday: Rest

Tuesday to Friday: Walk for 25 minutes at a moderate pace one day, 30 minutes the next.

Saturday: Walk 20 minutes fast.

Sunday: Walk 45 minutes at a moderate pace.

Advanced

Monday: Rest.

Tuesday to Friday: Walk 45 minutes at a moderate pace one day and 50 minutes the next day.

Saturday: Walk 50 minutes at a fast pace.

Sunday: Walk 60 minutes at a moderate pace.

Perfect your technique

To burn fat quickly and effectively, you should master power-walking. "Without it you will struggle to increase your pace and your weight loss will plateau," says Knight. Stand tall with your arms by your sides and pull your navel towards your spine so that your core muscles are working.

Focus your eyes five to six meters ahead and keep your shoulders relaxed. Bend your elbows at a 90 degree angle and cup your hands lightly, rather than clenching your fists.

Leading with the heel, take a step forward with your right foot and move your arms in opposition (i.e. as your left arm moves forward, your right moves back). Transfer your weight through the heel of your right foot.

"It is very easy, once you start concentrating on the movement, to forget about breathing," says Knight. "Try to get into a pattern, counting the number of steps to each in-and-out breath, making it the same each time."

Vary the terrain

Adding hills to your route will speed up calorie burning. "On really steep inclines, it's not unusual for even a fit person's heart rate to increase by about 20 percent," says Knight. Going downhill, you have to contract your leg muscles to work against gravity and slow your descent.

Walking on softer surfaces such as mud, sand or grass also uses more energy than walking on concrete. Every time your foot hits the ground, it creates a small depression so that the leg muscles must work harder to push upwards and forwards for the next step. Walking on cobblestones or rocky ground may have even more benefits.

Physiologists at the Oregon Research Institute have found cobblestone walking lowers blood pressure and improves balance. The uneven surfaces may stimulate acupressure points on the soles of the feet, regulating blood pressure. Because it is challenging, it will also burn more calories.

Walking styles

Think walking is boring? Then try these alternatives:

Nordic walking -- Nordic walking, which uses ski-like poles, has proven benefits. Professor John Pocari, an exercise physiologist at the University of Wisconsin, who has studied its effects, says using walking poles forces people to pick up their pace and work harder without realizing it.

"Just the fact that you are using your arms through a greater range of motion than normal means you burn more calories," says Pocari. On average, people use 20 percent more calories when they use poles. Participants in his studies increased their upper body strength by 40 percent and reduced impact on vulnerable hips, ankles and knees by 26 percent compared with running.

Mall walking -- Called 'mallercise' in the U.S., this was originally devised by doctors, who encouraged cardiac patients to incorporate indoor walking in shopping malls to hasten their rehab.

"It is a fantastic way to walk as you don't breathe in toxic car fumes, shopping centers are usually open seven days a week and good weather is guaranteed," says Knight.

Treadmills -- Because they are sprung, treadmills offer softer and easier terrain than a hard road, placing less strain on your joints, says Knight. This makes them a good option for people with joint or back problems. The downside is that, on a flat setting, they don't require the same level of exertion, so set them on a slight incline.