Aerobics is a form of exercise that is vigorous, rhythmic, and lasting long enough to keep the heart and lungs in good shape by increasing the blood flow and oxygen use of each organ.http://www.mayoclinic.com/health/aerobic-exercise/EP00002 During aerobic exercise the large muscles of the body such as the arms, legs and hips, are moved repeatedly. Aerobic exercise can include things such a jogging, bicycling, or swimming. The term "aerobics" is generally used to refer to a type of exercise that takes place in a group, usually with background music and directed by an instructor.

Some of health benefits that may be associated with aerobic exercise are cancer prevention and treatment, the increasing of bone density in women to fight the onset of osteoporosis, and the elevation of mood to fight depression.http://www.medicinenet.com/aerobic_exercise/page3.htm It may be used to fight cardiovascular disease, obesity, and as an aid in weight maintainence.http://www.medicinenet.com/aerobic_exercise/page3.htm

Aerobic exercise was originally developed by Dr. Kenneth H. Cooper, a physician at the San Antonio Air Force Hospital in Texas. He was training astronauts to go into space and was seeking a form of exercise that could fight coronary artery disease.http://www.cooperaerobics.com/About-Cooper/Dr--Kenneth-Cooper.aspx Cooper wrote a book called Aerobics in 1968. This book included exercise programs and was a success as people realized the value of these exercises for the general population.

Aerobics has evolved since its beginnings with Dr. Cooper and now there are many types of aerobics.

1. Low Impact Aerobics: Aerobic routines where one foot is always in contact with the floor.http://www2.gsu.edu/~wwwfit/aerobicd.html
2. High Impact Aerobics: This involves more vigorous movements than the low impact aerobics such as hops, skips, and jumps.http://www2.gsu.edu/~wwwfit/aerobicd.html
3. Water Aerobics: Exercises are performed in the shallow water of a swimming pool. It may mimic such moves as running or biking.http://www.fitnessproposals.com/fitness-accessories-articles/water-aerobics-equipment.htm
4. Step aerobics: Aerobics that incorporates a specially designed step with movements that are a series of dance steps.http://www2.gsu.edu/~wwwfit/aerobicd.html
5. Sport Aerobics: A competitive sport where competitors are judged on a one-minute, 45-second routine done to music.http://www.sportaerobics-nac.com/sportaerobics.htm