Exercise could be the best drug

by Dr Kenneth Gardner

As we focus on drug awareness month, there is still some debate whether physical exercise is a drug. Physical exercise, like any other psychoactive drug, will change the way we think, feel, and act because of the functional or pathological changes it causes in the central nervous system.

We perform physical activities for numerous reasons, thus, it is no wonder many health providers classify physical exercise as the miracle or wonder drug based on its benefits. According to the World Health Organization, lack of physical activity contributes to about 17 per cent of heart disease and diabetes, 12 per cent of the falls sustained by the elderly, and 10 per cent of all breast and colon cancers.

There is tremendous variation in the way we benefit from physical exercise. Some of us double our oxygen uptake, while those who exercise during middle age tend to enjoy better physical ability in later life.

Buffer against heart disease

There is a direct relation between physical inactivity and cardiovascular mortality. Physical inactivity is an independent risk factor for the development of coronary artery disease. There is also a dose-response relationship between the amount of exercise we perform based on our energy consumption and our energy expenditure and all the factors that cause death via cardiovascular disease in the middle aged and elderly.

The greatest potential for reduced mortality is in sedentary persons who become moderately active. The most beneficial effects of exercise on cardiovascular disease mortality are attained through moderate intensity activity. Both aerobic and anaerobic exercises increase the mechanical efficiency of our heart by increasing cardiac output and heart muscle size. After a heart attack, persons who remain sedentary have the highest risk of all causes of cardiovascular disease mortality.

Epidemiological evidence shows that moderate exercise has beneficial effects on our immune system, a decreased incidence of upper respiratory tract infections, and decreased inflammation associated with chronic disease in active relative to sedentary individuals due to its anti-inflammatory effects.

Fights depression

Physical activity increases blood flow and oxygen to the brain and is complemented by increased growth hormones that help create new nerve cells as a result of the increased production of chemicals for brain function and enhanced cognitive function. Physical activity increases the production and circulation of endorphins that act as natural pain relievers and antidepressants, which is responsible for the euphoric feeling that is sensed from intense physical exertion.

The increased production and circulation of endorphins and serotonin remains elevated several days after physical activity ceases but continues to contribute to the improved mood and self-esteem and prevention and treatment of depression. Physical exercise stimulates the production and emission of neurotransmitters that provide protection against neurodegenerative and neuromuscular diseases and reduces the risk of developing dementia and sleep disorders such as insomnia.

Dr Kenneth Gardner is an exercise physiologist at Holiday Hills Research Center; email: yourhealth@gleanerjm.com.