Ancient man has evolved as a hunter-gatherer. In other words, his metabolism is designed to allow for a physically active mode of existence and to obtain nutrition and sustenance from a mainly vegetarian diet. Hunting animals required a certain degree of social organisation, together with the necessary weapons, and living was generally quite dangerous. Both hunting and gathering demanded a certain level of physical activity and so, mans survival depended so much on his remaining mobile, that a broken limb could well have had catastrophic consequences. Exercise was not, therefore, a question of choice, but a necessity to survive (1). In terms of man’s basic diet, and the extent to which physical activity remained an integral part of his everyday existence, little has changed until very recent times.
The 20th century epidemics have been called the diseases of ‘civilisation’ since they are generally rare in Third World and developing countries. Coronary heart disease (CHD) and cancer are the major causes of premature disability and death in our own society, and deaths from infections are rare in comparison. To a large extent the burden of disease which Western society suffers at present is self-inflicted.
If we choose to smoke cigarettes and run the risk of lung cancer or heart disease, then we are doing so in the full knowledge of the possible consequences of our actions. During the past two decades, we have witnessed a tremendous increase in interest and participation in many forms of leisure-time activity. This phenomenon is vividly illustrated by the current mass participation in marathon running and ‘aerobics.’ So great has the interest become that we are quite accustomed to hearing about the ‘fitness boom’ or the ‘leisure industry.’ (1) Ashton. D / Davies. B, Why exercise? Expert medical advice to help you enjoy a healthier life (Basil Blackwell, 1986)
Participation in mass exercise, at least in the UK, is predominantly a twentieth century phenomenon. Since it is quite clear that our bodies have evolved to allow for a physically active mode of existence, and since in this day and age this has become increasingly difficult (and in some cases arguably impossible) the questions arise of, firstly; what implications this has for our long-term health, and secondly, what we can do to compensate for this long-term lack in physical activity. The other obvious issues such as the long term effects of regular prolonged exercise and the dangers of over-exercising also arise. This discourse will aim to answer these questions in a well-rounded and satisfactory manner.
The benefits of exercise extend far beyond just losing weight and physique management. Research has shown that regular physical activity can help reduce the risk of several diseases and health conditions and improve overall quality of life (2). The effects of exercise on CHD have been examined by assessing the consequences of both occupational activity and leisure activity. Blair et al (1989) examined the role of generalised physical fitness and health status in 10,224 men and 3,120 women for eight years and concluded that physical fitness was related to a decrease in both mortality rates (all cause) and coronary heart disease (3). Daily physical activity can help to prevent heart disease and stroke by strengthening the heart muscle, lowering blood pressure, raising high-density lipoprotein (HDL) levels, lowering low-density lipoprotein (LDL) levels, improving blood flow, and increasing the working capacity of the heart.
(2) Health Benefits of Exercise – Accessed on 13/4/05 (Nutristrategy, 2005) http://www.nutristrategy.com/health.htm (3) Ogden. J, Health Psychology: A textbook (Open University Press, 2004) Optimising each of these factors can provide the additional benefit of decreasing the risk of Peripheral Vascular Disease. Regular physical activity can reduce blood pressure in all individuals, and this is of great benefit to those individuals with generally high blood pressure as this is one of the major causes of heart attacks and stroke. Physical activity also reduces body fat, which is associated with high blood pressure and by reducing the content of fat in the body, physical activity can help to prevent and control Noninsulin-Dependent Diabetes.
Exercise may be related to improved glucose control, resulting in a reduction in the possible effects of the disease. Another benefit of exercise is that physical activity helps to reduce body fat by building and/or preserving muscle mass and improving the body’s ability to use calories in an efficient manner. When physical activity is combined with a balanced diet and the right kind of nutrition, it can help to control weight and prevent obesity which is a major risk factor for many diseases.
By increasing muscle strength, endurance and improving flexibility and general posture, regular exercise can also help to prevent back pain (an ailment that many adults suffer from). Regular weight-bearing exercise promotes bone formation and may prevent many forms of bone loss (such as osteoporosis) associated with aging. Cardiovascular exercise such as running and jogging, have been shown to postpone the development of disability in older adults. These include mild conditions such as rheumatism and muscle stiffness.
Studies on the psychological effects of exercise have found that regular physical activity can improve mood levels and self-esteem. McDonald and Hodgdon (1991) carried out a meta-analysis of both the correlational and experimental research into the association between depression and exercise. It was concluded by them that aerobic exercise was related to a decrease in depression and that this effect was greatest in those individuals that displayed higher levels of the initial depressive symptoms (4). In short, the physical benefits of exercise are; increased muscle size, strength in ligaments for posture, improved and more efficient cardiovascular function, improved physical work effort, and a changing, healthier body composition.
In the UK and the USA in particular, where obesity is as high as 60% in some States, getting people to exercise who are engaged in a sedentary lifestyle has proved to be a big problem (5). Primarily, people cannot be forced to exercise, but they can be encouraged. The question arises then, of how best to go about this, and which groups can and should be targeted first. First and foremost, the two different groups that could be formulated in relation to this area are occupation centred (i.e. encouragement in the workplace) and school/child centred (relating to encouragement in the classroom).
This would be wise since the majority of the population are in full-time employment, or are in some form of educational establishment. Different techniques could then be attempted. For the occupation centred strategy, employers could be given incentives to increase the level of employee awareness of the value of increased physical activity and how to exercise safely. They could do this by providing employees with educational information on physical activity in company newsletters, placing posters on bulletin boards and using table tent cards in break rooms and cafeterias. Access to educational information that is online could be given, and the management could organise special charity runs or negotiate special deals with local gymnasiums if an agreed number of employees sign up