Key Messages

• Adolescents and young adults, both male and female, benefit from physical activity. 
• Physical activity need not be strenuous to be beneficial. 
• Moderate amounts of daily physical activity are recommended for people of all ages. This amount can be  obtained in longer sessions of moderately intense activities, such as brisk walking for 30 minutes, or in shorter sessions of more intense activities, such as jogging or playing basketball for 15-20 minutes. 
• Greater amounts of physical activity are even more beneficial, up to a point. Excessive amounts of physical  activity can lead to injuries, menstrual abnormalities, and bone weakening. 
 

Facts

• Nearly half of American youths aged 12-21 years are not vigorously active on a regular basis. 
• About 14 percent of young people report no recent physical activity. Inactivity is more common among females (14%) than males (7%) and among black females (21%) than white females (12%). 
• Participation in all types of physical activity declines strikingly as age or grade in school increases. 
• Only 19 percent of all high school students are physically active for 20 minutes or more, five days a week, in physical education classes. 
• Daily enrollment in physical education classes dropped from 42 percent to 25 percent among high school students between 1991 and 1995. 
• Well designed school-based interventions directed at increasing physical activity in physical education classes 
have been shown to be effective. 
• Social support from family and friends has been consistently and positively related to regular physical activity. 
 

Benefits of Physical Activity

• Helps build and maintain healthy bones, muscles, and joints. 
• Helps control weight, build lean muscle, and reduce fat. 
• Prevents or delays the development of high blood pressure and helps reduce blood pressure in some adolescents with hypertension. Regular physical activity that is performed on most days of the week reduces the risk of developing or dying from some of the leading causes of illness and death in the United States. Regular physical activity improves health in the following ways: 
• Reduces the risk of dying prematurely. 
• Reduces the risk of dying prematurely from heart disease. 
• Reduces the risk of developing diabetes. 
• Reduces the risk of developing high blood pressure. 
• Helps reduce blood pressure in people who already have high blood pressure. 
• Reduces the risk of developing colon cancer. 
• Reduces feelings of depression and anxiety. 
• Helps control weight. 
• Helps build and maintain healthy bones, muscles, and joints. 
• Helps older adults become stronger and better able to move about without falling. 
• Promotes psychological well-being