Amount of physical activity by children steadily declines as they get older

Jul 15, 2008

New research documents the decline in physical activity among children, with less than a third meeting recommended physical activity guidelines by the time they are 15 years old, according to a study in the July 16 issue of JAMA.

Physical inactivity is associated with an increase in obesity and associated illness and chronic diseases among youth. Expert opinion and studies suggest that children need a minimum of 60 minutes of moderate-to-vigorous physical activity (MVPA) per day, according to background information in the article. How many youth meet this standard is unclear.

Philip R. Nader, M.D., of the University of California San Diego, La Jolla, and colleagues collected physical activity data on 1,032 children when they were 9 years old until they were age 15. Physical activity was measured by the children wearing an accelerometer, a monitor worn on a belt that records minute-by-minute movement counts. The children would wear this monitor for one week a year at ages 9,11,12 and 15. The study took place in 10 geographic locations from 2000-2006. Participants included boys (517 [50.1 percent]) and girls (515 [49.9 percent]); 76.6 percent white (n = 791); and 24.5 percent (n = 231) lived in low-income families.

The researchers found that both the average minutes of MVPA and the range of minutes spent in MVPA decreased as children moved into adolescence. At 9 years, children engaged in MVPA approximately 3 hours per day on both weekdays and weekends. By 15 years, adolescents were only engaging in MVPA for 49 minutes per weekday and 35 minutes per weekend day. At 9 and 11 years, almost all children met the guidelines (of 60 minutes of MVPA per day), but by 15 years, only 31 percent and 17 percent met guidelines on weekdays and weekends, respectively. Both weekday and weekend MVPA showed significant decreases in MVPA between 9 and 15 years, with decreases of 38 and 41 minutes per year, respectively.

The estimated age at which girls crossed below the recommended 60 minutes of MVPA per day was approximately 13.1 years for weekday activity compared with boys at 14.7 years, and for weekend activity, girls crossed below the recommended 60 minutes of MVPA at 12.6 years compared with boys at 13.4 years.

"More research is … needed to understand the reasons for such substantial decreases in youth activity. Further study and more precise descriptions of the immediate activity environment, such as whether youth are located in urban, suburban, or rural areas; availability of safe places to be active; and quality of school-based physical education may explain some of the individual and regional differences noted in this and other studies."

"This decrease augurs poorly for levels of physical activity in U.S. adults and potentially for health over the course of a lifetime. Consequently, there is a need for program and policy action as early as possible at the family, community, school, health care, and governmental levels to address the problem of decreasing physical activity with increasing age," the authors conclude.

Source: JAMA and Archives Journals

Explore further: Tax forms could pose challenge for HealthCare.gov

add to favorites email to friend print save as pdf

Related Stories

Best friends can make a child more physically active

Jan 17, 2011

Boys and girls who take part in physical activity with their best friend in the neighbourhood where they live have higher levels of physical activity, new research has found.  With many children not doing ...

Recommended for you

Can YouTube save your life?

Aug 29, 2014

Only a handful of CPR and basic life support (BLS) videos available on YouTube provide instructions which are consistent with recent health guidelines, according to a new study published in Emergency Medicine Australasia, the jo ...

Doctors frequently experience ethical dilemmas

Aug 29, 2014

(HealthDay)—For physicians trying to balance various financial and time pressures, ethical dilemmas are common, according to an article published Aug. 7 in Medical Economics.

AMGA: Physician turnover still high in 2013

Aug 29, 2014

(HealthDay)—For the second year running, physician turnover remains at the highest rate since 2005, according to a report published by the American Medical Group Association (AMGA).

Obese or overweight teens more likely to become smokers

Aug 29, 2014

A study examining whether overweight or obese teens are at higher risk for substance abuse finds both good and bad news: weight status has no correlation with alcohol or marijuana use but is linked to regular ...

User comments : 0