As a nation of largely sedentary workers, we take less and less exercise. Yet one of the most simple forms is also the most effective - walking. There is now evidence to suggest that regular brisk walks could be as good for us, if not better, than strenuous jogging.
Read our guide to why walking really is a good workout.
What does walking do to your body?
Regular walking, like most aerobic activities, is good for you because cardio-vascular exercise strengthens the heart and lungs, increasing overall fitness.
Together with diet and other exercise plans, it can also help with weight loss and tone up muscles.
Dr Craig Williams a sports science lecturer at the University of Exeter is a firm believer in the benefits of walking, and says: 'It can improve muscle endurance as well as muscle strength, especially in the lower body.
'It is good for bones and improves the body's cardiovascular system. It also helps boost circulation.
'Power-walking - keeping a brisk pace at moderate to high intensity - can burn the same amount of calories as jogging or running. So it is useful for helping with weight loss.'
And, he adds: 'Because it is lowimpact, it does not have the same potential for injury as jogging. Yet it can offer all the benefits.'
Marcus Davis, an osteopath with the Harley Street Back Centre in London, agrees. He says: 'Walking helps to drain the lower legs of excess fluid and can help prevent varicose veins through the pumping action of the calf muscles.
'The increased supply of oxygen exercise promotes also gets rid of the waste products in the tissues.
'And because more people are able to walk at a consistent speed than run, it is a more beneficial form of tissue-cleansing, particularly for the over-50s, for whom jogging can actually cause more problems.'
'Walking is also better for the spine than running, as it puts less stress on the discs. Yet we were designed for constant movement, not sitting in cars or in front of computers, which causes negative pressures on our spinal cord.
'Regular walking is excellent for spinal discs, which receive minerals and vitamins through the pumping action it causes.
'And the best thing is that you can see results from walking reasonably quickly - although it depends on each person's individual level of fitness, age and how often and fast they are walking.'
What does it do to your feet?
The key players in regular walking are, of course, your feet. And we don't use them in the best way.
'Our feet were made for walking. And that's exactly what they should do,' says David Goysett, expert podiatrist at the Third Space Medical centre in London's Soho. It's the best way of exercising the 50-odd muscles we have in our feet.
'This is becoming increasingly important as we become more sedentary. Just like any other muscle in the body, you have to exercise it to keep it healthy and able to maintain its function. When you don't exercise them, the muscles become weaker.
'The 26 bones within the foot, plus its ligaments, are exercised gently by walking, so they are not in danger of stress.'
At the end of a long walk, Goysett recommends you give your feet a gentle massage. 'It's a good idea to stretch them out, much as you would any other muscle after exercise. That should reduce any aches and pains the following day.'
How to do it best
Nicki Waterman, fitness trainer for the GMTV Inch Loss Beach regime, points out that although we learn to walk as infants, very few of us have continued to walk correctly.
For instance, a slight 'bounce' while walking not only slows you down, but also places a strain on joints.
Nicki advises that when taking a step, let the heel land first. 'If you think about how your body weight is distributed, it makes sense to land the foot in a heel-to-toe motion.
'And as you take the movement from heel towards the ball of the foot, try to make a slight rolling motion inwards. This will help to give you more power when you push off with your foot. The result will be a faster stride.'
Walking can burn just as many calories as jogging if you walk with a special technique.
Nicki says: 'I call it the racewalking wiggle. If you walk with a slight swivel in your hips with each stride, it makes you move faster. Yes, it can make you look a little strange but, mile for mile, it uses the same calories as you would if you were jogging.'
Maintaining your posture also makes a huge contribution in obtaining the maximum benefits from walking. Nicki recommends walking tall and also holding the ribcage up and tummy muscles in.
This means you get an additional midriff work-out while walking. 'I also advise my clients to squeeze their bottoms as they walk since this tightens the gluteus maximus muscles.
'I tell them to imagine they are holding a £50 note between the cheeks, so that they achieve a firmer bottom and also get a more effective walking session.'
How often should you do it?
Government health recommendations are for us to exercise for 30 minutes daily, for a minimum of five days a week. But you can split the walk into a couple of 15-minute journeys each day or make up for lost time with an extra-long walk at the weekend.
Dr Craig Williams says: 'Where walking beats other forms of exercise is that there are excellent strategies for boosting the amount you do.
'For example, getting off at an earlier bus-stop than your usual one will add on a two to three minute walk. That may not sound much, but if you do that twice a day, every day, it all adds up.
'Other tips include walking up a flight of stairs instead of taking the lift. Even a brisk walk around the block for ten minutes in your lunchbreak contributes to your daily walking.'
How to keep it up?
There are also psychological benefits to walking. Pete Cohen, GMTV's Life Coach for the Inch Loss Beach series, says: 'When you walk, just like any other form of exercise, your body has a chemical release of serotonin, the natural feelgood chemical.
'There is also the release of endorphins, which are happy hormones, which is why people feel on a natural high at the end of an exercise session. Remembering how you feel should be an incentive for you to keep it up.'
Nicki Waterman suggests linking up with a 'walking buddy'.
'If you have a commitment to meet a friend for that walk, you are less likely to cancel. Whereas if you are planning to walk on your own, it is often easier to make excuses and put it off.
Read more at Daily Mail.