Physical Inactivity is a leading cause of death today.
Globally, six percent of deaths are attributed to physical inactivity. This follows high blood pressure (13%), tobacco use (9%) and is equal to high blood glucose (6%).
Moreover, physical inactivity is the main cause for approximately 21–25% of breast and colon cancers, 27% of diabetes and 30% of ischaemic heart disease burden.
Physical activity is any bodily movement produced by the skeletal muscles that uses energy. This includes sports, exercise and other activities such as playing, walking, doing household chores, gardening, and dancing. A healthy lifestyle needs physical activity, sports is a choice.
– Global Recommendations for Physical Activity by the WHO
In the past, the role of physical activity as a life-style modulating factor has been considered as that of a tool to balance energy intake. Although it is important to avoid obesity, physical inactivity should be discussed in a much broader context.
There is accumulating epidemiological evidence that a physically active life plays an independent role in the protection against type 2 diabetes, cardiovascular diseases, cancer, dementia and even depression. For most of the last century, researchers sought a link between muscle contraction and humoral changes in the form of an ‘exercise factor’, which could be released from skeletal muscle during contraction and mediate some of the exercise-induced metabolic changes in other organs such as the liver and the adipose tissue.
We have suggested that cytokines or other peptides that are produced, expressed and released by muscle fibres and exert autocrine, paracrine or endocrine effects should be classified as ‘myokines’. Given that skeletal muscle is the largest organ in the human body, our discovery that contracting skeletal muscle secretes proteins sets a novel paradigm: skeletal muscle is an endocrine organ producing and releasing myokines, which work in a hormone-like fashion, exerting specific endocrine effects on other organs. Other myokines work via paracrine mechanisms, exerting local effects on signalling pathways involved in muscle metabolism. It has been suggested that myokines may contribute to exercise-induced protection against several chronic diseases.
Physical activity is defined as any bodily movement produced by skeletal muscles that requires energy expenditure. Physical inactivity is a global public health problem – Physical inactivity has been identified as the fourth leading risk factor for global mortality causing an estimated 3.2 million deaths globally.
In Europe, physical inactivity is considered the number two actual cause of death (Bronnum-Hansen et al., 2007) and the Centers for Disease Control and Prevention have designated physical inactivity as an actual cause of chronic disease (Mokdad et al., 2004).
On average, physically inactive people have a life span that is 5 years shorter than that of physically active people. Moreover, the expected lifetime without long-standing illness is reduced by approximately 8 years in physically inactive people (Bronnum-Hansen et al., 2007).
Regular moderate intensity physical activity – such as walking, cycling, or participating in sports – has significant benefits for health.
For instance, it can reduce the risk of cardiovascular diseases, diabetes, colon and breast cancer, and depression. Moreover adequate levels of physical activity will decrease the risk of a hip or vertebral fracture and help control weight.
– Source: WHO
Exercise can be as effective as many frequently prescribed drugs in treating some of the leading causes of death, according to a new report. The study raises important questions about whether our health care system focuses too much on medications and too little on activity to combat physical ailments.
For the study, which was published in October 2013 in BMJ, researchers compared how well various drugs and exercise succeed in reducing deaths among people who have been diagnosed with several common and serious conditions, including heart disease and diabetes.
Type 2 diabetes, cardiovascular diseases, colon cancer, breast cancer, dementia and depression constitute a cluster of diseases, which defines ‘a diseasome of physical inactivity’. Both physical inactivity and abdominal adiposity, reflecting the accumulation of visceral fat mass, are associated with the occurrence of the diseases within the diseasome. Physical inactivity appears to be an independent and strong risk factor for accumulation of visceral fat, which again is a source of systemic inflammation. Chronic inflammation is involved in the pathogenesis of insulin resistance, atherosclerosis, neurodegeneration and tumour growth.
Evidence suggests that the protective effect of exercise may to some extent be ascribed to the anti-inflammatory effect of regular exercise, which can be mediated via a reduction in visceral fat mass and/or by induction of an anti-inflammatory environment with each bout of exercise. The finding that muscles produce and release myokines provides a conceptual basis to understand the mechanisms whereby exercise influences metabolism and exerts anti-inflammatory effects. According to our theory, contracting skeletal muscles release myokines, which work in a hormone-like fashion, exerting specific endocrine effects on visceral fat. Other myokines work locally within the muscle via paracrine mechanisms, exerting their effects on signalling pathways involved in fat oxidation.
– Prof. Bente Klarlund Pedersen in “The diseasome of physical inactivity–and the role of myokines in muscle–fat cross talk”