Walking for health: why GPs need to be involved
Walking has been described as 'the nearest activity to perfect exercise' Professor Ken Fox shows why your patients should step out for health
ard evidence of the impact of walking on disease prevention and treatment is now compelling. Moderately intense physical activity is associated with dramatic reductions in risk of coronary heart disease, colon and breast cancer, diabetes and obesity, and can improve psychological and social well-being.
A sedentary person is more than twice as likely to suffer serious health problems than the reasonably active equivalent. This is now established throughout the world. The combined effects on these problems of taking up activity are unknown but are likely to be even greater than the single disease estimates have shown.
A recent analysis of the Women's Health Initiative Observational Study data (73,000 women) in the New England Journal of Medicine (Manson et al, 2002) indicated that volume of walking produced a strong graded inverse relationship with coronary and cardiovascular events.
Findings held up for women in each decade of middle and old age, for black as well as white women and for overweight women.
Results also held up regardless of the speed and intensity of the walking, although extra benefits were apparent for regular brisk walking. Additionally, time spent sitting had a further independent contribution to risk. These types of data are backed up by interventions that have shown that walking can improve lipid profile, reduce blood pressure, and contribute to weight loss and psychological well-being.
Activity patterns and culture
Scientific evidence needs to be accompanied by plausible and intuitive explanation and there are no obvious reasons.
The human form originated somewhere in the African savannah around four million years ago and developed the capacity to walk long distances in search of food.
It is hardly surprising physiologists find we are ideally suited to endurance walking and storage of energy in fat reserves. Ironically, two key features of human survival are redundant and in the case of efficient energy storage can be a serious handicap in the modern world.
High-energy dense cheap food is available 24 hours a day. We neither need to forage for energy nor store it. Perhaps we should not be shocked at the tripling of the incidence of obesity in the UK in the last 20 years.
One in five UK adults is now clinically obese, carrying the concomitants of diabetes, heart disease, arthritis and cancer.
The National Heart Forum last year calculated 37 per cent of coronary heart disease is a direct result of inactivity. Put bluntly, we are now biologically inept for the highly technological, take-it-easy culture we have created for ourselves.
There has been a steady decline over the past decades in distance walked per year. This figure is directly related to rising car ownership.
Children's activity patterns reflect similar changes. In 1986, 60 per cent of school journeys were on foot and this had dropped to 49 per cent by 1996, with car transport increasing from 16 to 29 per cent.
Evidence indicates walking at even light levels of intensity carries benefits. If the epidemic of obesity is caused by reductions in physical activity, then moving body weight around is an important means of increasing daily energy expenditure.
Roughly 100-150kcal/mile of energy are used in walking according to body weight. One of the few advantages of being overweight is that more energy is used. Increased intensity where there are sensations of mild breathlessness and increasing body heat will bring further benefits to the cardiovascular and metabolic system.
Moderate activity has been shown to increase HDL cholesterol, lower total cholesterol, mildly reduce blood pressure, and improve the overall condition of the circulatory-respiratory and musculoskeletal systems. Walking more quickly or including hills in the walk will help. By far the most important factor is frequency.
Regularity is the key to experiencing the long-term effects and the aim should be to build sessions of walking into the daily routine. Some schemes have found cheap pedometers (costing about £5) are very helpful in motivating people to achieve more steps per day. A target of 10,000 steps has been put forward as the goal for walking for health. The average office day produces about 3,000 steps.
National recommendations for physical activity for health are 30 minutes of brisk walking or its equivalent on five or six days a week. This can be achieved in smaller 'bite-sized chunks' to get a similar effect. The choice of walking as the benchmark is logical.
All injury-free, able-bodied individuals are capable of walking, it is the one activity that is acceptable and familiar in all cultures, ethnic and socio-economic groups. Sport on the other hand carries the tag of athleticism. In the Allied Dunbar National Fitness Survey, the main reason middle-aged and older adults gave for not being active for health was 'because I am not the sporty type'.
Walking is relatively free from injury, involving low-impact work with minimal twisting and turning. It can be built up steadily and safely from the home base, it can be sociable in groups, and does not require the expense of the health club.
In short it has been described recently as 'the nearest activity to perfect exercise'. For the GP, an added advantage is that walking does not carry the same litigious implications that perhaps exercise referral schemes have.
Increasing walking is a complex challenge as it involves action at the individual and environmental level. Persuading patients to walk is of little help if the locality in which they live is dangerous or threatening. Central government must provide directives and incentives through local and regional partnerships in their transport and building plans and their educational provision, primary care trusts and dedicated charities.
Already the Scots are ahead of the game and have a Walking Strategy for Scotland in the consultation phase.
Finnish and Danish campaigns have improved levels of walking and cycling.
It is time to take walking seriously.
Benefits of walking
· Reduced risk of cardiovascular disease and coronary events
· Reduced risk of diabetes
· Improved insulin sensitivity and glycaemic control
· Control of mild hypertension
· Reduced risk of colon and breast cancer
· Improved psychological
· Improved mobility and independence for older people
· Attenuation of weight gain
· Regeneration of communities
· Reduced traffic and road accidents
· Reduced air and noise pollution
· Opportunities for social interaction especially for the elderly and children
Walking for health: why GPs need to be involved
How GPs can help
· Join the battle to establish the importance of walking for health
· Convince patients more walking is achievable and beneficial
· Encourage your primary care trust to engage in partnerships to increase walking
· Encourage planning partnerships to improve the built environment for walking
· Make some pedometers available to patients
· Walk more yourself