2.01 (V) Exercise
Body movement is a fundamental component of human health, evolution, and development. Like many other mammals, humans are made to move, hunt, and run away from predators. But at the same time, humans are also evolved to conserve energy through limiting movement when the opportunity is available. Physical activity is defined here as any type of body movement that uses up energy. Opportunities for physical activity in the modern world are becoming less all the time. The modern world offers an environment where there are ample opportunities to conserve energy. Cars are the dominant mode of transportation. Most jobs are office-based and there are unlimited temptations for sedentary forms of recreation such as tablets, computers, TV, and video games. Only about half of the adult population in Australia meet the core physical activity guideline that is set to two and a half hours of moderate to vigorous physical activity a week. And less than 2 in 10 adults meet the full guideline that also includes participation in strength exercise. In other words, the modern world has removed the need to move in our daily life. Instead, we try to compensate through designer movement such a sports and gym-based activities known as exercise. However, the number of people exercising in the population is disappointingly low because of time, cost, physical conditioning, and skill barriers. Clinical exercise programs aimed at treating or managing chronic conditions are not standard practice and it can be difficult to implement due to low participation. Incidental activity, that is everyday physical activity, may be more feasible for many people. We will now see how physical activity and exercise relate to mental health and well-being. Almost half of the Australian population has experienced some form of mental disorder at some point in their lifetime. The commonest mental health conditions are depression and anxiety. In the World Health Organization recognizes depressive disorders as the leading cause of disability worldwide. Additionally, developing and implementing physical activity and exercise interventions in these population groups is a big challenge because of the existence of multiple physical comorbidities that may limit capacity to exercise and the relatively low priority assigned to a healthy lifestyle by these population groups. There is a lot of overlap between major lifestyle diseases and mental health conditions. For example, between 31 and 45% of patients with coronary artery disease suffer from clinical depression while people with cardiovascular disease, in general, are two to three times more likely to develop depression compared with the general population. This can trigger a vicious circle whereby mental and physical health problems exacerbate each other and both jointly reduce the ability to be physically active leading to worsening health. Physical activity is recommended as an evidence-based treatment for depression by health authorities. Several systematic reviews have highlighted the potential physical activity for the treatment of mild to moderate depression. The value of exercise for more severe forms of depression is less clear, perhaps due to the chicken and egg effect where depression causes reduced motivation for activity and less activity makes the depression worse. For mental health as well as physical health conditions, an ounce of prevention worth a pound of cure. It is far more cost-effective to prevent the onset of disease rather than seeking to cure them. It is not clear what types of exercise and physical activity are most effective. Most studies have tested aerobic types like walking and running, and fewer studies have tested resistance training or activities like yoga and Tai Chi. All types seem to work reasonably well. The ideal type of physical activity is perhaps less important than the long term participation in physical activity. Unfortunately, the mental health benefits of physical activity are temporary. Sustained participation in exercise programs among mental health patients is very challenging. We do not know the best way to help patients to become and remain physically active in their everyday life or stick to an exercise program. Social isolation and loneliness increase the risk for depression and people suffering from depression are less likely to have strong social networks. Therefore, physical activity and exercise programs that involve group interaction may be a promising option. We prefer to design a program that suits the preferences and circumstances of each individual as this will increase the chances of longterm adherence. This has been a brief introduction to physical activity in mental health. We saw that physical activity plays a big role in the prevention and management of major mental illness. Achieving the minimum recommendations of 150 minutes of moderate to vigorous physical activity per week would be an excellent start for people with stressful lives who are currently sedentary. Those achieving these recommendations could strive for 300 minutes per week and more engagement in higher intensity physical activity. The most important aspect of the physical activity component of a treatment plan is that recommended activities are enjoyable and achievable, so that the patient adheres to them in the long term. If moderate to intense activity is not an option, light incidental activity can also be beneficial. Incidental activity can be embedded into everyday lifestyles and includes walking or cycling to work, using stairs instead of lifts, taking active breaks from continuous sitting, and replacing short to medium car trips with walking or cycling. For established depression, deliberate scheduling of everyday activities like walking to the shops and doing other errands are encouraged for overcoming lack of motivation and fatigue that often come with depression.