Have you ever wondered why it is so important to exercise and practice sports? What are the health benefits of physical activity and exercise practice? When did we start noticing about this positive effects and why are they more important now than ever?Join us for this read and find out!
The World Health Organization refers to health as ‘physical, mental, and social well-being, not merely the absence of disease and infirmity’. Advantages of regular exercise for maintaining good health and curing disease have long been well known. Records of organized exercise for good health have been found since ancient Chinese history, back in 2500 BC. Hippocrates (460–370 BC) and later Galen (129–210 AD) recognized the need to promote and prescribe exercise for health-related benefits, and to provide general medical care for the athletic individual. ‘Lack of activity destroys the good condition of every human being, while movement and methodical physical exercise saves and preserves it’ as stated by Plato (427–347 BC).
The first empirical evidence about the advantages of physical exercises was demonstrated by a group of researchers in London early in the 1950s. Significant inverse relationship between physical activity and coronary heart disease were showed among the London bus conductors. Less active conductors were prone to higher rate of coronary heart disease. Other comparative studies were performed among postmen and other clerks, which demonstrated good health and longevity of active clerks compared to less active groups. Since then, numerous scientific clinical and comparative studies proved the importance of exercise for promotion of good health and better disease staging.
The metabolic effects of exercise
Exercise is one of the most frequently prescribed therapies both in health and disease. Indeed, the beneficial effects of exercise on metabolism both in healthy and pathological conditions, for the prevention and treatment of disease, is fully accepted among experts and the general public. Metabolism is the crucial chemical transformation within the cells of all living organisms, aimed at: 1) conversion of ingested food to energy for the cellular processes; 2) conversion of food to building blocks of the organisms (e.g. lipids, proteins, nucleic acids); and 3) elimination of the toxic compounds (e.g. nitrogenous wastes) from cells. These purposes are succeeded through a set of enzyme-catalysed reactions that allow an organism to grow and reproduce, to maintain their structures and respond to environment. Enzymes act as catalysts, speeding up the reactions, either breaking down glucose or building up cellular components (e.g. proteins, lipids). Usually, breaking down releases energy and building up consumes energy, named total energy expenditure, crucial for the healthy status of each living individual.
It is now established that physical exercise can significantly influence the rate (speed) of metabolism, which in turn determines how much food an organism will require and how it is able to obtain that food. Exercise can positively enhance total energy expenditure and the resting metabolic rate, calories burn during resting condition, boosting up the process of achieving good health. Recent research suggests that modest increments in energy expenditure due to physical activity (~1000 kcal per week) or an increase in physical fitness of one metabolic equivalent is associated with lowering mortality by about 20%. Exercise can also increase intermediate metabolism, including digestion and transport of substances into different cells. A clinical study including middle-aged women showed that inactive women faced 52% higher mortality rate, 50% higher incidence in cardiovascular diseases and metabolic disorders, and 29% increased cancer related mortality compared to active individuals.
Exercise and disease
Advantages of physical activity are evident, not only in healthy individuals but also in diseased persons having various pathological conditions. Randomized clinical trials have shown that treatment of chronic diseases can be well managed by doing regular physical exercise. Recent evidence supports prescribing exercise in the primary and secondary prevention of pulmonary and cardiovascular diseases (coronary heart disease, chronic obstructive pulmonary disease, hypertension, intermittent claudication); metabolic disorders (type 2 diabetes, dyslipidemia, obesity, insulin resistance); non-alcoholic fatty liver disease and non-alcoholic steatohepatitis; muscle, bone and joint diseases (rheumatoid arthritis, fibromyalgia, chronic fatigue syndrome, osteoporosis); cancer; and depression. It is believed that chronic metabolic diseases including non-alcoholic fatty liver disease, which is the higher abnormal accumulation of fat in liver cells and non-alcoholic steatohepatitis, which is the aggressive and inflammatory stage of non-alcoholic fatty liver disease, are greatly prevented and treated by doing regular physical exercise. In fact, bad dietary habits and sedentary life style (lack of proper physical activity) are the route to these pathological condition, which makes exercises the proper solution to avoid diseased states.
In conclusion, exercise is beneficial for metabolism both in healthy and pathological conditions. Exercise should be considered as a treatment option for many conditions and as such dosing of exercise should also be carefully considered.
Tawhidul Islam (ESR-8) is doing his PhD at the Faculty of Pharmacy of the University of Lisbon (FFUL), Portugal.