Estimated reading time: 8 minutes
Evidence based
Exercise is defined as an ‘activity requiring physical effort, carried out to sustain or improve health and fitness’.
There are many types of physical activity; including, running, jogging, walking, swimming, cycling, playing football and dancing, to name a few.
Physical activity has been linked with health and longevity since ancient times (1). It is now accepted that physical inactivity is a fundamental cause of several chronic diseases, including cardiovascular disease, obesity, osteoporosis and some cancers.
Our daily lives are becoming less physically active, while organized exercise and training is on the rise.
EXERCISE CAN:
· Increase life span
· Reduce risk of developing cardiovascular disease
· Prevent and lower high blood pressure
· Improve cholesterol and triglyceride levels
· Lower risk of developing colon cancer
· Strengthen bones
· Reduce pain
· Reduce stress, anxiety and symptoms of depression
· Have significant positive effects in preventing or alleviating mental illness
· Aid weight loss and build muscles
· Prevent and help manage diabetes
· Increase production of anti-inflammatory cytokines and reduce Th2 response in asthma
· Enhance cognitive performance
· Prevent and treat lower back problems
· Boost your energy levels
· Improve sleep
(2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 19, 21)
Benefit 1: REDUCE RISK OF ILLNESS AND ALL-CAUSE MORTALITY
Evidence strongly indicates that mortality rates are 20-80% lower in active fit men and women of all ages. Expending 1000 kcal per week in physical activity is sufficient, greater amounts of activity are likely to produce greater benefits. Vigorous exercise is probably more effective (1). Regular moderate and reasonable amounts of vigorous activity can aid the immune system in fighting disease and reduce incidence of colds.
Benefit 2: PREVENT CARDIOVASCULAR DISEASE (CVD)
There are many forms of CVD, including coronary heart disease, atherosclerosis, high blood pressure, stroke, and heart failure. Exercise protects against CVD through decreasing sympathetic activity, blood pressure, heart rate, inflammation and production of reactive oxygen species (ROS); while increasing the heart muscles’ ability to pump oxygen-rich blood = increasing blood flow and blood vessel dilation (3, 4). A single session of exercise has the potential to lower blood pressure for several hours thereafter (1, 3).
Frequent exercise can increase HDL-cholesterol (often referred to as good cholesterol), lower total cholesterol, LDL-cholesterol and triglycerides (1). Physical activity can improve insulin sensitivity (3). Insulin is a hormone that helps the body control the level of glucose in the blood. High insulin sensitivity allows the cells of the body to use blood glucose more effectively, reducing blood sugar. As with blood pressure, effects may be seen following a single session and frequent exercise is required for continued benefit (1).
Exercise can reduce the risk factors associated with CVD in people with type 2 diabetes. More studies are needed to identify tailored exercise plans, but resistance training has been shown useful for primary treatment of vascular diseases and maintenance of vascular function in type 2 diabetes patients (6).
Benefit 3: PREVENT CANCER
Increasing levels of physical activity are associated with reductions in the risk of several site-specific cancers (1). At least 30 minutes of moderate activity per day may be needed for reduction of colon cancer. More vigorous exercise has been shown beneficial to reduce breast cancer risk in some studies; however, findings are inconsistent.
The potential mechanisms may include changes to metabolic factors (in particular insulin), avoidance in weight gain and improved immune surveillance. As for colon cancer, decreased bowel transit time is one of the proposed mechanisms (1).
Benefit 4: IMPROVE BONE HEALTH
Bone is a dynamic tissue that responds to changes in the internal or external environment. Bone mass increases during growth and reaches a peak towards the age 20. It remains fairly stable until about 50 years, after which progressive loss begins. Strong evidence suggests that weight bearing physical activity plays a key role in the normal growth and development of a healthy skeleton.
Physically active women who include walking for exercise, have a lower risk of osteoporotic fracture (1). Even though the potential of exercise to augment bone mineral in the mature skeleton is small. In pre-menopausal women its effect is mainly conservation while in older women its effect is to reduce the rate of bone loss.
Benefit 5: PROTECT AGAINST MENTAL ILLNESS
Emerging evidence suggests that physical activity may protect against depression, anxiety and stress disorders. There is robust evidence that structured and supervised physical activity, including aerobic and resistance training, can improve multiple outcomes in major depression, pre/postnatal depression, anxiety/stress disorders and schizophrenia. Emerging evidence suggests a potential role for physical activity in bipolar disorder and alcohol use disorders (2, 8). Interestingly, it doesn't seem to matter how intense your workout is. It seems that your mood can benefit from exercise no matter the intensity of the physical activity (9).
Benefit 6: AIDS WEIGHT LOSS & PREVENTS TYPE 2 DIABETES
Regular exercise has been shown to increase metabolic rate, which will burn more calories and help you lose weight (12, 13). Excess weight is strongly associated with increased risk of both metabolic syndrome and type 2 diabetes. There is strong evidence that even a moderate amount of weight loss achieved through changes in diet and exercise can greatly reduce the risk of developing type 2 diabetes (14). Physical activity can reduce your chance of type 2 diabetes by up to 40% (15).Type 2 diabetes results from the body's ineffective use of insulin. As previously mentioned, exercise can improve insulin sensitivity (3).
Recent studies indicate that moderate-intensity aerobic physical activity training could reduce haemoglobin A1c (HbA1c) by 0.66%. This is close to the effect of intense glucose-lowering pharmacological treatment found in the UK Prospective Diabetes Study’ (16).A 1% decrease in the HbA1c value is associated with a 15%-20% decrease in major cardiovascular events and a 37% reduction in microvascular complications. Diabetes UK recommends at least 150 minutes (2.5 hours) of moderate to vigorous-intensity physical activity each week plus muscle-strengthening activity twice a week (for adults 19-64). Activity can be spread out through the day into bite-size chunks (30 minutes, 5 days a week) (15).
Benefit 7: REDUCE DIABETIC KIDNEY DISEASE (DKD)
The incidence and prevalence of diabetes, primarily type 2 diabetes, have grown significantly throughout the world. This overall increase in the number of people with diabetes has had a major impact on development of DKD, one of the most frequent complications of both types of diabetes (17).
The benefits of exercise are very well recognized in the general population and in people with type 2 diabetes. Some uncertainties about physical activity recommendations for type 1 diabetes patients stem from the fact that strenuous exercise may worsen albuminuria immediately after the activity. However, regular moderate to vigorous physical activity have shown to reduce incidence and progression of DKD (4).
Benefit 8: IMPROVE POLYCYSTIC OVARY SYNDROME (PCOS)
Regular exercise is recommended for women with PCOS. It results in statistically significant improvement in menstrual cycle pattern, hirsutism (unwanted, male-pattern hair growth in women), body mass index, weight, waist circumference waist-hip ratio. Addition of metformin resulted in added benefits (18).
Benefit 9: HELP IMPROVE BRAIN HEALTH & MEMORY
The brain and its functions might be influenced by several factors such as physical exercise, ageing, stress, environment and diet. There are several ways exercise can improve the brain. First, exercise will increase blood flow to the brain, providing the brain with essential nutrients such as glucose and oxygen.
Physical exercise plays a critical role on brain plasticity (brain’s ability to change throughout life) and neurogenesis (the development of new neurons in the brain). Scientists pinpoint the effects to a chemical called brain-derived neurotrophic factor (BDNF), a molecule that fuels much of the mental activity, learning and memory (19). The levels of BDNF are decreased in many neurodegenerative diseases. Exercise boosts the release of this neurotransmitter, along with other beneficial brain chemicals, such as dopamine and serotonin.
Benefit 10: REDUCE INCIDENCE OF AUTOIMMUNE DISEASE
Autoimmune diseases are characterized by tissue damage and loss of function due to an immune response that is directed against specific organs. The incidence of many autoimmune diseases has been found to be higher in people less engaged in physical activity.
Physical activity leads to elevation in T-regulatory cells (subpopulation of T cells that modulate the immune system, maintain tolerance to self-antigens and prevent autoimmune disease), produces a shift in the Th1/Th2 balance and promotes the release of anti-inflammatory cytokines.
Physical activity has been shown to be safe in most of autoimmune diseases (20):
Rheumatoid arthritis: milder disease course, improved joint mobility and CVD profile
Multiple sclerosis: decreased fatigue, enhanced mood, cognitive abilities and mobility
Type 1 diabetes: decreased risk of autonomic neuropathy and CVD
Fibromyalgia: decreased disease severity and pain, better quality of life
Systemic lupus erythematosus: enhanced quality of life and better CVD profile
HOW MUCH EXERCISE DO I NEED?
Physical activity should be encouraged from birth, through floor-based play and water-based activities (15). Most guidelines recommend achieving at least 150 minutes per week of moderate-intensity exercise (30 minutes, 5 times a week), 75 minutes per week of vigorous-intensity exercise, or a combination of the 2. In addition, all individuals should strive for at least 2 days per week of resistance training activity (3, 14, 15).
However, even the easiest activity is better than nothing. Also, it is important to choose physical activity that works for you and your body and start gently and gradually.
There are some negative effects, such as the risk of failure, injuries, eating disorders, burnout and exercise-induced gastrointestinal tract discomfort, however these aspects are more common in elite-level sports (2).
Image source:Pexels: Victor Freitas, Dorothy Castillo
Written by:Jana Papajova
References:
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2. Malm, C. Jakobsson, J. and Isaksson, A. (2019). ‘Physical Activity and Sports - Real Health Benefits: A Review with Insight into the Public Health of Sweden’. Sports,7(5), p.127.
3. Tian, D. and Meng, J. (2019). ‘Exercise for Prevention and Relief of Cardiovascular Disease: Prognoses, Mechanisms, and Approaches’. Oxidative Medicine and Cellular Longevity, 2019, pp.1-11.
4. Pongrac Barlovic, D. Tikkanen-Dolenc, H. and Groop, P. (2019). ‘Physical Activity in the Prevention of Development and Progression of Kidney Disease in Type 1 Diabetes’. Current Diabetes Reports, 19(7).
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15. Diabetes.org.uk. (2019). Getting active and staying active. [Online]. Available at: https://www.diabetes.org.uk/guide-to-diabetes/managing-your-diabetes/exercise.
16. Pai, L. Chang, P. Chen, W. et al. (2012). ‘The effectiveness of physical leisure time activities on glycaemic control in adult patients with diabetes type 2: A Systematic Review’. JBI Library of Systematic Reviews, 10, pp.1-20.
17. Tuttle, K. Bakris, G. Bilous, R. et al. (2014). ‘Diabetic Kidney Disease: A Report From an ADA Consensus Conference’. American Journal of Kidney Diseases, 64(4), pp.510-533.
18. Tiwari, N. Pasrija, S. and Jain, S. (2019). ‘Randomised controlled trial to study the efficacy of exercise with and without metformin on women with polycystic ovary syndrome’. European Journal of Obstetrics, Gynecology, and Reproductive Biology,234, pp.149-154.
19. Lee, M. Byun, K. Kim, J. et al. (2019). ‘Trends in exercise neuroscience: raising demand for brain fitness’. Journal of Exercise Rehabilitation, 15(2), pp.176-179.
20. Sharif, K. Watad, A. Bragazzi, N. et al. (2018). ‘Physical activity and autoimmune diseases: Get moving and manage the disease’. Autoimmunity Reviews,17(1), pp.53-72.
21. Dolezal, B. Neufeld, E. Boland, D. et al. (2017). ‘Interrelationship between Sleep and Exercise: A Systematic Review’. Advances in Preventive Medicine, 2017, pp.1-14.
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