Unfit? Start here.

Just a little walking will do it. Jim Pollard explains how even very unfit men can double their life chances.

You're probably not a regular reader of the journal Medicine and Science in Sports and Exercise so you may well have missed the good news they published in 2009.

At least, it's good news for people who aren't particularly interested in physical exercise. The news is this: you don't have to be particularly fit to enjoy enormous health benefits. Yes, I'll repeat that, you don't have to be particularly fit to enjoy enormous health benefits. What you need to do is to avoid is being totally unfit.

A study led by Dr Sandra Mandic, of the University of Otago in Dunedin, New Zealand, of nearly 4,400 healthy US adults, found that the 20% with the lowest physical fitness levels were twice as likely to die over the next nine years as the 20% with the next-lowest fitness levels.

In other words, if you can get yourself out of the least fit 20% of the population, you can double your survival chances.

Ah, you say, but it's not just about physical fitness, it's about weight and blood pressure. You're right, of course, but this study took that into account proving just how important it is to get off the couch and get physically active, even if you have an otherwise healthy lifestyle. (Nor is it all down to genetics. In other studies, levels of exercise have been a clear indicator of longevity even in twins.)

Dr Mandic told Reuters: 'Our findings suggest that sedentary lifestyle, rather than differences in cardiovascular risk factors or age, may explain the two-fold higher mortality rates in the least-fit versus slightly more fit healthy individuals.

Nearly two-thirds of the least-fit study participants were not getting the minimum recommended amount of exercise - at least 30 minutes of moderate activity, like brisk walking, on five or more days a week.

Her study assessed 4,384 middle-aged and older adults between 1986 and 2006. Fitness levels were assessed with treadmill tests and each participant was followed for an average of about nine years. When participants were divided into five groups based on fitness levels, they found:

• Fittest 20% - 1 in 17 died during the study period
• 2nd Least fit 20% - 1 in 8 died
• Least fit 20% - 1 in 4 died.

Another key factor is that you must be doing exercise now. The fact that you were super-fit fifteen years ago doesn't make a lot of difference. Overall, the five groups showed little difference in their reported exercise habits over their adult lives. Where they did differ was their activity levels in recent years.

'Since it is recent physical activity that offers protection,' Mandic said, 'it is important to maintain regular physical activity throughout life.' And since fitness is linked to longevity regardless of weight and health conditions like high blood pressure and high cholesterol, exercise is important for all, according to Mandic. That, she said, includes people who are thin and in generally good health.

Sounds good but what do you do?

If you're in the least fit half of the population and want to take up exercise, you may be worried about  injuries, heart problems and so on. Clearly if you haven't exercised for a long time or are overweight, have a heart or other serious health problelm, then you should tell your doctor what you're planning. But in most cases there won't be a problem because all I'm suggesting is a little bit of walking.

For last month's Harvard Men's Health Watch (HMHW), two scientists sifted through 4,295 articles published on walking between 1970 and 2007 and chose the 18 best observational studies. When they pulled together the results from the 18 studies, they found that walking reduced the risk of heart problems by 31% and cut the risk of dying during the study period (on average about 11 years) by 32%. Benefits were equal in men and women.

Even walking just 5.5 miles per week and at a pace as casual as about 2 miles per hour cut the risk.

The greatest benefits went to people who walked longer distances, walked at a faster pace, or both.

HMHW then went on to give some great advice on walking and to chellenge some of the popular myths about it.

Myth 1: 'Walking's no good because it's not aerobic'

You may be a bit sceptical about this. For many years the watchword in exercise has been aerobic and for most of us walking isn't that. (Aerobic means with oxygen and that means you need to have your heart working about 60-80% of its maximum for over 20 minutes.)

But you don't have to exercise aerobically to benefit. Exercise is about the intensity, duration and frequency. So you may have to walk for longer than you'd need to job but you'll still benefit.

Myth 2: 'Walking takes too long'

Yes you'll have to walk for longer than you run but walking requires no preparation. Jogging, by contrast, if you're doing it properly, does. Healthy running requires warming-up, warming-down, changing clothes twice and having a shower - factor these in and the time differences narrow considerably.

Myth 3: 'Observational studies aren't clinical trials'

True but the clinical trial gold standard requires double-blind testing. In other words, one group of walkers would need not to know that they were actually walking. Not too easy to arrange. So observation is as good as it gets for this sort of lifestyle-related research.

But the Harvard study does cite one clinical trial in which had some random element. A 10-year study of postmenopausal women randomly assigned one mile walking a day or told to continue normal activities found that walkers had an 82% lower risk of heart disease.

As well as rebutting the myths, Harvard Men's Health Watch come up with some advantages for walking over other more vigorous forms of exercise.

Fact 1: 'Walkers rarely get injured'

You're far less likely to get injured through walking than running. According to HMHW, each time they land, runners subject their bodies to a stress equal to about three times their body weight. Some put it higher than that.

HMHW estimate that in just one mile, a typical runner's legs will have to absorb more than 100 tons of impact force. They say: 'It's a testament to the human body that running can be safe and enjoyable. At the same time, though, it's a testament to the force of gravity that walkers have a much lower (1% to 5%) risk of exercise-related injuries than runners (20% to 70%).' That is a big difference.

Fact 2: 'Walking is not a bolt-on activity'

Unlike most forms of exercise, no special arrangements, skills, training or clothes are needed for walking. It can be part of everyday life. Walk to work, walk to the shops, walk the dog, walk to the tube. Park your car some way away from where you're going and walk to and from that. 

Best of all, walk up the stairs. As an activity this betters even weight-lifting. HMHW cite an admittedly small Canadian study which monitored 17 healthy male volunteers with an average age of 64 while they walked, lifted weights, or climbed stairs. Stair climbing was twice as taxing as brisk walking on the level and 50% harder than lifting weights. But they add a health warning for the less-fit: 'Begin modestly with a flight or two, and then add more as you improve.'

'To stay well', HMHW conclude, 'walk for 30 to 45 minutes nearly every day. Do it all at once or in chunks as short as five to 10 minutes. Aim for a brisk pace of three to four miles an hour, but remember that you'll get plenty of benefit from strolling at a slower pace as long as you stick with it.'

Further information

• For more getting started information on malehealth follow the links on the right or the drop down menus under Online Gym.
• More on ideas for getting active your way from the NHS