Wikipedia
Physical exercise
Physical exercise is any bodily activity that enhances or maintains physical fitness and overall health. It is performed for many different reasons. These include strengthening muscles and the cardiovascular system, honing athletic skills, weight loss or maintenance and for enjoyment. Frequent and regular physical exercise boosts the immune system, and helps prevent the "diseases of affluence" such as heart disease, cardiovascular disease, Type 2 diabetes and obesity.Hu., F., Manson, J., Stampfer, M., Graham, C., et al. (2001). Diet, lifestyle, and the risk of type 2 diabetes mellitus in women. The New England Journal of Medicine, 345(11), 790-797. Retrieved October 5, 2006, from ProQuest database. It also improves mental health, helps prevent depression, helps to promote or maintain positive self-esteem, and can even augment an individuals sex appeal. Childhood obesity is a growing global concern and physical exercise may help decrease the effects of childhood obesity in developed countries.
Classification
Types of exercise
Exercises are generally grouped into three types depending on the overall effect they have on the human body:
* Flexibility exercises, such as stretching, improve the range of motion of muscles and joints.OConnor, D., Crowe, M., Spinks, W. 2005. Effects of static stretching on leg power during cycling. Turin, 46(1), 52-56. Retrieved October 5, 2006, from ProQuest database.
* Aerobic exercises, such as cycling, swimming, walking, rowing, running, hiking or playing tennis, focus on increasing cardiovascular endurance.Wilmore, J., Knuttgen, H. 2003. Aerobic Exercise and Endurance Improving Fitness for Health Benefits. The Physician and Sportsmedicine, 31(5). 45. Retrieved October 5, 2006, from ProQuest database.
* Anaerobic exercises, such as weight training, functional training or sprinting, increase short-term muscle strength.de Vos, N., Singh, N., Ross, D., Stavrinos, T., et al. 2005. Optimal Load for Increas read more at » http://en.wikipedia.org/wiki/Physical+exercise