Presented by the National Physical Activity Plan
The proportion of U.S. children and youth attaining 60 or more minutes of moderate-to-vigorous physical activity on at least 5 days per week receives a grade of D-.
Roughly one quarter of U.S. children and youth 6-15 y of age meet the 2008 Physical Activity Guidelines for Americans recommendation of at least 60 minutes of moderate-to-vigorous physical activity per day [15, 17]. Data for the primary indicator were obtained objectively using accelerometers during the National Health and Nutrition Examination Survey (NHANES). In addition to these objective data, recently released results from the combined 2012 NHANES and NHANES National Youth Fitness Survey (NNYFS) corroborated these findings . In the more recent report, 24.8% of youth 12-15 y of age reported obtaining 60 minutes of moderate-to-vigorous physical activity every day . Meeting the recommendations differs by gender, age group, and ethnicity, with males, younger children, and non-white ethnicities being more active than their female, older, and white ethnicity counterparts, see Figures 3 and 4 [19, 20].
HEAlTH BENEFITS ASSOCIATED WITH MODERATE-TO-VIGOROUS PHYSICAl ACTIVITY
Cardiovascular and metabolic health benefits associated with habitual physical activity vary across the activity intensity spectrum; higher intensity activities, such as playing basketball and jogging, are associated with greater health benefits than those at lower energy intensities, such as walking. A longitudinal study from Finland found that youth who remained active during a 6-year follow-up period had more favorable cardiometabolic risk profiles than those remaining inactive. The active boys showed significantly lower insulin and triglyceride concentrations, as well as lower adiposity and a more beneficial ratio of HDL to total cholesterol, than the inactive boys. Girls who remained active had lower triglycerides and lower adiposity
The grade of D- indicates that the majority of American children and youth do not meet physical activity recommendations. According to NHANES, approximately one quarter of children and youth 6-15 y of age were at least moderately active for 60-minutes per day on at least 5 days per week .
Results from The European Youth Heart Study also showed significant correlations between physical activity and cardiovascular and metabolic disease risk factors, including higher fitness, and lower adiposity, waist circumference, systolic and diastolic blood pressure, glucose, insulin, cholesterol, triglycerides, and insulin resistance .
WHAT ABOUT LIGHTER INTENSITY ACTIVITIES?
As discussed above, moderate-to-vigorous physical activity is associated with numerous health benefits in children and youth, but lower intensity activities still convey health benefits and are important for inactive children just beginning a physical activity routine, especially for those overweight or obese. According to data from the 2003-06 NHANES, among youth ages 12-19 y, light-intensity physical activities were associated with more favorable cardiometabolic health markers, including lower diastolic blood pressure and higher HDL cholesterol . The data also reflect that youth spend more time engaged in lighter intensity activities rather than moderate-to-vigorous physical activity. On average, the youth spent only 19 minutes per day in moderate-to-vigorous physical activity, but significantly more time, approximately 350 minutes per day, engaged in light-intensity physical activities . Though greater health benefits are seen in youth participating in higher intensity physical activities, the health benefits associated with lighter intensity activities and the time differential between time spent in MVPA versus light activities warrant greater emphasis on how light activity can complement moderate-to-vigorous physical activity throughout childhood.