Exercise has many health benefits. Exercise is good for you. These are things we hear constantly on the radio, the tv, read about in the papers and magazines, are told by doctors and talk about with friends and family. Yet many of us, it would seem, just don’t believe it or why else would obesity be on the increase in the United States and the United Kingdom? We either don’t believe what we are told or we simply don’t understand the health benefits exercise can give us.
Here, I shall try to explain simply the health benefits, exercise can have simply with regard to body fat.
Fat tissue and body composition
Regular exercise increases the number of calories that people expend, decreases the amount of fat in the bloodstream and increases the amount of lean tissue in the body.
People who are not used to taking exercise tend to be poor at expending calories. When they do exercise they become breathless and tire quickly, so that activity tends to be of short duration. Fit people who are accustomed to exercise can keep going for longer periods and burn calories more efficiently. Regular aerobic exercise prevents obesity by using fat for fuel and by speeding up the basal metabolic rate (the rate at which the body ‘ticks over’). People with a high metabolic rate burn calories faster even when they are resting.
Muscle-strengthening exercise builds up muscle fibres, which also speeds up the metabolic rate. Having a high percentage of muscle in relation to fat also raises energy levels, so that people are more likely to be active in everyday life. This has the effect of burning off even more fat.
One of the reasons that unfit people cannot exercise for long periods is that they quickly begin to produce a substance called lactic acid. This accumulates in the muscles and blood, interferes with the way that muscle fibres contract and causes a feeling of muscle fatigue and exhaustion. Until the body has rid itself of excess lactic acid, it can be difficult or even impossible to carry on exercising. Fit people have a higher anaerobic threshold than unfit people, which means that it takes longer for them to produce lactic acid or that they clear it from the body more efficiently than unfit people.
Regular moderate exercise has been shown to reduce the levels of damaging fats, such as cholesterol, that circulate in the bloodstream. This is thought to help prevent the development of atherosclerosis, the narrowing of the arteries that is caused by the build up of fatty deposits. Since atherosclerosis is one of the main causes of coronary artery disease, this is thought to be an extremely valuable benefit of regular exercise.
Despite the fact that people in the West are actually eating less than they used to, they are becoming fatter. This is believed to be as much to do with physical inactivity as it is to do with diet. Excess body fat is a risk factor for heart disease and diabetes, and constantly carrying extra weight causes the joints to wear out. Even thin people can carry quite a lot of body fat if they do not take aerobic exercise. If you have a lot of fat and little muscle you may constantly feel weak and tired. Excess fat that is stored under the skin or around internal organs is called adipose tissue. In men, adipose tissue tends to occur around the upper arms, chest and; in women it occurs on the upper arms, breasts, abdomen, hips, buttocks and thighs.
Regular exercise improves the ratio of muscle to fat in the body. Toned muscles also improve the contour of the body, making it look tight and defined rather than flabby. Exercise can also have an impact on posture, making the body seem slimmer and taller.
Research indicates that inactivity and high body fat are damaging to women of all ages. Girls who have a high percentage of body fat may start their periods several years earlier than girls with less fat. An early onset of menstruation is thought to be one of the risk factors for breast cancer.
Taking regular aerobic exercise of moderate intensity for half an hour up to five times a week will help to reduce body fat if combined with a healthy low-fat diet. Approximately 90 per cent of people who simply follow a low-calorie diet are likely to regain lost weight within a year.
So, I believe the health benefits exercise has on the body are pretty easy to understand, see below for related articles.