Exercise and Effects of Ageing

Until recently, physiologists thought that the deterioration of the human body over time was inevitable, and that ageing naturally involved a gradual reduction in lung and heart function, bone-density, muscle power, tissue elasticity and immunity. Yes, it is true that the bodily functions are not as they were when we were younger, but we now know that much of this decline is due to the fact that most older people have stopped exercising and have actually, simply seized up.

Regular exercise is one of the best ways to slow the effects of ageing, and offers both physical and mental benefits. Ideally, the exercise habit should be maintained throughout life, although it is never too late to start, as the human body is tremendously adaptable and can easily recover from one or two decades of inactivity. Because people’s lifestyles and priorities as well as their physical condition change over the years, it is important to tailor an exercise programme to the individual’s age, fitness level and personal needs and preferences. As ever, the ideal programme should balance aerobic training to maximize aerobic capacity, strength training to build muscle and bone, and stretching to maintain flexibility.

Anyone, young or old, embarking on a fitness programme for the first time (or resuming exercise after a long break) should start gently and build up gradually.

EFFECTS OF AGEING

All the vital organs become less efficient with age, but the decrease in performance of the heart and blood vessels and the lungs have particularly wide-ranging effects on our physical condition and sense of well-being. The rate at which the heart pumps blood around the body drops by 30 percent between the ages of 30 and 70. The blood vessels become increasingly narrow and rigid and this process, called atherosclerosis, is linked with high blood pressure, which in turn can lead to heart disease and stroke.

The lungs start to stiffen and shrink early in midlife, and the total lung capacity halves by the age of 70. Aerobic capacity – the rate at which oxygen is taken into the bloodstream and carbon dioxide is removed – declines by ten per cent every ten years after the age of 25. Older people therefore have to breathe much harder during exercise to keep the blood oxygenated.

The average person loses about 35 per cent of their muscle between the ages of 30 and 70. Women in particular can become very weak in old age, because they have less muscle than men. The more muscle we have, the more calories we burn. Muscle loss therefore lowers the body’s metabolic rate, which results in fat gain. Being overweight raises blood pressure and cholesterol levels, places a strain on the organs and joints, and increases the risk of adult-onset diabetes.

Another effect of ageing is osteoporosis, in which the bones decrease in density and mass, becoming weak and brittle and prone to fractures. In young people, tiny cavities in the bone caused by the breakdown of bone cells are soon filled with new bone. In older people, however, the rate of bone loss outstrips new production. An adequate intake of calcium is vital for healthy bone regeneration, but exercise is also important because it helps to build bone mass. The hormone oestrogen plays an important role in building bone, and older women are particularly prone to bone loss because of the drop in oestrogen levels after the menopause. However, both men and women can be affected by osteoporosis.

All of these factors interact to keep fit people mobile and independent into old age, and several surveys show that fit people live longer. In later life, they are less prone to injuries from falls, less likely to have a heart attack and have a much lower risk of developing cancer.

Different types of exercise offer different benefits. Aerobic exercise protects against heart disease and can take at least ten years off the ageing of the heart and lungs. Weight-bearing exercise – any exercise that you do on your feet with your bones supporting your weight – helps to build strong bones and slows down bone loss in later life. Strength training effectively counteracts muscle loss, raises the body’s metabolic rate