Physical Activity - 2014
The World Health Organisation defines physical activity as any bodily movement produced by skeletal muscles that requires energy expenditure. Physical activity can take a number of forms. Exercise is a form of physical activity that is generally planned, structured, and repetitive which aims to improve or maintain one or more aspects of physical fitness.1 Sport also requires physical exertion, and or physical skill, which by its nature or organisation is competitive.2Incidental activity is physical activity that is undertaken as part of carrying out normal daily life, such as climbing the stairs or walking the dog.3 Physical activity can also be categorised in terms of its function and effect, including resistance, aerobic, incidental, and active transport.
While physical activity forms part of the body’s energy balance equation, all too often the benefits of physical activity are only considered in relation to obesity and weight loss. The benefits of physical activity extend much further. Regular participation in physical activity is known to reduce the risk of physical health problems such as cardiovascular disease and stroke, type 2 diabetes, hypertension, some cancers and osteoporosis.4,5
Due to the release of endorphins, physical activity can also improve mood.6 Regular participation in physical activity improves both short- and long- term psychosocial wellbeing by reducing feelings of stress, anxiety and depression.7 There is scientific evidence to suggest physical activity can alleviate the symptoms of depression and it may also be useful in the treatment of mild to moderate depressive disorder.8 A recent review confirmed the role of physical activity in reducing the symptoms of depression, but noted some methodological concerns and called for future research to consider the types and duration of physical activity that would provide the most benefit for those people with depression.9
Physical activity may also provide additional benefits for those who are already suffering from chronic health conditions. Based on estimates that between 60 and 70 per cent of the Australian population is sedentary, or has low levels of physical activity, it has been suggested that increasing participation in physical activity by 10 per cent would lead to opportunity cost savings of $258 million, with 37 per cent of savings arising in the health sector.10
A lack of physical activity, or physical inactivity, has been identified as the fourth leading risk factor for global mortality. Estimates suggest that physical inactivity is the principal cause for approximately 21-25 per cent of breast and colon cancer disease burden, 27 per cent of diabetes, and 30 per cent of ischemic heart disease burden worldwide.
Vigorous intensity physical activity (eg jogging or other aerobic exercise) generally provides increased health benefits.11 However, it is important to recognise that some of the biggest health gains are made by those individuals who transition from being physical inactive (sedentary) to moderate amounts of physical activity. Evidence suggests that activities such as walking for half an hour a day on five days a week may increase life expectancy by 1.5 to 3 years.12
Infants should be engaged in supervised, floor based play from birth (0-1 year);
Toddlers and preschool aged children (1-3, 3-5) should be physically active for at least three hours per day spread throughout the day;
Children aged two years and under should not spend time watching TV or using other electronic media. For children aged 2-5 years, these activities should be limited to less than one hour per day; and
For children aged 5-12 years, at least 60 minutes (and up to several hours) of moderate to vigorous physical activity every day.
The documented health benefits of exercise among children and youth include increased physical fitness (cardio and muscular strength), reduced body fat, favourable cardiovascular and metabolic disease risk profiles, enhanced bone health, and reduced symptoms of depression.20
Physical activity over the life span
Consistent findings around an inverse association between physical activity and cancer risk (with evidence around breast and colon cancer showing the biggest risk reductions);
Physical activity has been linked to improved outcomes for those undergoing organ transplantation;26
Physical activity has also been linked with reduced morbidity and mortality from cardiovascular disease;
Physical activity is associated with improved quality of life among those patients who have had a cardiac event;
Physical activity also has a significant role in the prevention (and management of) type 2 diabetes, which is a growing health problem worldwide;
Physical activity is also associated with lower levels of psychological distress, including depression.27
In addition, certain types of physical activity during childhood and adolescence convey a reduced susceptibility to fractures related to reduced bone density. Similarly, physical activity that focuses on improving balance in the elderly helps to reduce the chance of a fall.
Physical activity can also play an important role in the management of many chronic diseases, by reducing some aspects of disease progression and improving quality of life. Medical practitioners should be consulted during the development of physical activity plans for individuals with single or multiple chronic diseases.
For adults, there are some forms of physical activity that have increased rates of injury. In some instances, safety equipment may be used to reduce risk of injury. There are also risks associated with participation in too much exercise, particularly among those who have previously been sedentary. There is some risk inherent in the participation in almost all forms of exercise and sport. However, the benefits largely outweigh the risks, and efforts should be made to encourage participation.
Trained first responders who have completed specific training in advanced first aid should be in attendance at sporting events with large numbers of participants because they can provide initial clinical management, prior to the arrival of paramedics or other medical professionals. Automated external defibrillators (AEDs) should be accessible in all places where people participate in physical activity. Timely use of AEDs can improve chances of survival for those individuals who suffer from a sudden cardiac event.
Elite athletes may suffer from injury due to large amounts of physical activity. Injuries are usually specific to the sport, and are often managed by medical professionals who specialise in treating athletes.
- There must be appropriate opportunities for all people to engage in physical activity;
- All doctors should opportunistically advise patients and parents of the potential health benefits of increased physical activity, especially for sedentary children and adults;
- There must be increased investment in research examining the risks and benefits (to both the individual and the community) of participating in various forms of physical activity, as well as evaluations of interventions that aim to increase participation in physical activity;
- There must be improved data collection on physical activity levels within the population, including collection of information on formal and incidental physical activity. This data collection should also include appropriate representation from specific population groups, including children and adolescents, the elderly, Aboriginal and Torres Strait Islanders, and those from culturally and linguistically diverse backgrounds.
- Physical education and physical activity must be universally incorporated into school curricula. Schools must be universally funded to support such activity;
- Opportunities to engage in physical activity should also be supported by institutions, including (but not limited to) those providing post-secondary education, aged care facilities, hospitals and prisons;
- Opportunities to engage in physical activity should also be promoted within the workplace;
- Governments must extend their focus on support for elite athletes to support of more physical activity opportunities for all Australians.
- All possible steps be taken to maximise the safety of the environments in which exercise is performed. This includes appropriate first aid facilities and equipment, including AEDS. For larger events first responders should be in attendance.
- A health assessment by a medical practitioner should be performed before someone is encouraged to undertake vigorous physical activity.
Published: 18 Jun 2014