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Physical fitness has always been important part of life. It is theorised that when people left a hunter-gatherer lifestyle and formed fixed communities based around agriculture that physical fitness levels declined. This is not to say that levels of physical labour decreased but that the type of work undertaken was not necessarily as conducive to a general level of fitness. As such, regimented fitness regimes were either invented or became more common. This was especially the case in classical civilisations such as Ancient Greece and Rome. In Greece especially physical fitness was considered to be an essential component of a healthy life and it was the norm for men to frequent a gymnasium. Physical fitness regimes were also considered to be of paramount importance in a nation's ability to train soldiers and field an effective military force. Partly for these reasons, organised fitness regimes have been in existence throughout known history and evidence of them can be found in many countries.
Developing research has demonstrated that many of the benefits of exercise are mediated through the role of skeletal muscle as an endocrine organ. That is, contracting muscles release multiple substances known as myokines, which promote the growth of new tissue, tissue repair, and various anti-inflammatory functions, which in turn reduce the risk of developing various inflammatory diseases.
To get in top physical shape, you’ll need to work on three different areas of cardiorespiratory fitness. Capacity is the amount of work you can do, such as how fast you can perform a sprint or dash. Stamina refers to how long you can exercise. For example, a sprinter is faster than a marathon runner, but probably can’t run as long or as far as the marathoner. Anaerobic conditioning helps you work at very high intensities and helps you recover more quickly afterward. For example, many basketball players have no problem making fast breaks down the court, but afterward, you see them grabbing their knees, gasping for breath as they try to recover. Interval training consists of many high-intensity bursts of activity, each followed by a recovery period. These recovery periods, which occur many times during an interval workout, help you improve your ability to catch your breath after a point or play and recover for the start of the next one.
Studies have shown that physical activity can improve mental health and well-being.This improvement is due to an increase in blood flow to the brain and the release of hormones. Being physically fit and working out on a consistent and constant basis can positively impact one's mental health and bring about several other benefits, such as the following.
These recommendations are also widely supported by the American Cancer Society. The guidelines have been evaluated and individuals that have higher guideline adherence scores substantially reduce cancer risk as well as help towards control with a multitude of chronic health problems. Regular physical activity is a factor that helps reduce an individual’s blood pressure and improves cholesterol levels, two key components that correlate with heart disease and Type 2 Diabetes. The American Cancer Society encourages the public to "adopt a physically active lifestyle" by meeting the criteria in a variety of physical activities such as hiking, swimming, circuit training, resistance training, lifting, etc. It is understood that cancer is not a disease that can be cured by physical fitness alone, however, because it is a multifactorial disease, physical fitness is a controllable prevention. The large associations tied with being physically fit and reduced cancer risk are enough to provide a strategy to reduce cancer risk. The American Cancer Society asserts different levels of activity ranging from moderate to vigorous to clarify the recommended time spent on a physical activity. These classifications of physical activity consider the intentional exercise and basic activities are done on a daily basis and give the public a greater understanding of what fitness levels suffice as future disease prevention.