Nav: Home

19-year-olds as sedentary as 60-year-olds, study suggests

June 15, 2017

Physical activity among children and teens is lower than previously thought, and, in another surprise finding, young adults after the age of 20 show the only increases in activity over the lifespan, suggests a study conducted by researchers from the Johns Hopkins Bloomberg School of Public Health. And, the study found, starting at age 35, activity levels declined through midlife and older adulthood.

The study also identified different times throughout the day when activity was highest and lowest, across age groups and between males and females. These patterns, the researchers say, could inform programs aimed at increasing physical activity by targeting not only age groups but times with the least activity, such as during the morning for children and adolescents.

The findings, which were published online June 1 in the journal, Preventive Medicine, come amid heightened concern that exercise deficits are contributing to the growing obesity epidemic, particularly among children and teens.

"Activity levels at the end of adolescence were alarmingly low, and by age 19, they were comparable to 60-year-olds," says the study's senior author, Vadim Zipunnikov, assistant professor in the Bloomberg School's Department of Biostatistics. "For school-age children, the primary window for activity was the afternoon between two and six P.M. So the big question is how do we modify daily schedules, in schools for example, to be more conducive to increasing physical activity?"

For their study, the researchers used data from the National Health and Nutrition Examination Survey from the 2003-2004 and 2005-2006 survey cycles. The 12,529 participants wore tracking devices for seven straight days, removing them for only bathing and at bedtime. The devices measured how much time participants were sedentary or engaged in light or moderate-to-vigorous physical activity. The researchers broke down findings into five age groups: children (ages six to 11); adolescents (ages 12 to 19); young adults (ages 20 to 29); adults at midlife (ages 31 to 59); and older adults (age 60 through age 84). Forty-nine percent were male, the rest female.

Activity among 20-somethings, the only age group that saw an increase in activity levels, was spread out throughout the day, with an increase in physical activity in the early morning, compared to younger adolescents. The increase may be related to starting full-time work and other life transitions.

For all age groups, males generally had higher activity levels than females, particularly high-intensity activity, but after midlife, these levels dropped off sharply compared to females. Among adults 60 years and older, males were more sedentary and had lower light-intensity activity levels than females.

The study confirmed that recommended guidelines were not being met. For instance, the World Health Organization (WHO) recommends at least 60 minutes of moderate-to-vigorous physical activity a day for children ages five to 17 years. The study found that more than 25 percent of boys and 50 percent of girls ages six to 11 and more than 50 percent of male and 75 percent of female adolescents ages 12 to 19 had not met the WHO recommendation.

While WHO formulates its recommendations in terms of moderate-to-vigorous activity, the researchers say there is a growing consensus for the benefits of reducing sedentary behavior and increasing even low-intensity levels of physical activity.

"The goal of campaigns aimed at increasing physical activity has focused on increasing higher-intensity exercise," says Zipunnikov. "Our study suggests that these efforts should consider time of day and also focus on increasing lower-intensity physical activity and reducing inactivity."
-end-
"Re-evaluating the effect of age on physical activity over the lifespan" was written by Vijay R. Varma, Debangan Dey, Andrew Leroux, Junrui Di, Jacek Urbanek, Luo Xiao and Vadim Zipunnikov.

The research was supported by the National Institutes of Health (grants 5R01HL123407-02, 5R01AG049872-02, 5R01AG050507-02). Vijay R. Varma was supported by the Intramural Research Program, the National Institute of Aging.

Johns Hopkins University Bloomberg School of Public Health

Related Physical Activity Articles:

Physical activity in lessons improves students' attainment
Students who take part in physical exercises like star jumps or running on the spot during school lessons do better in tests than peers who stick to sedentary learning, according to a UCL-led study.
Physical activity may attenuate menopause-associated atherogenic changes
Leisure-time physical activity is associated with a healthier blood lipid profile in menopausal women, but it doesn't seem to entirely offset the unfavorable lipid profile changes associated with the menopausal transition.
Are US adults meeting physical activity guidelines?
The proportion of US adults adhering to the 'Physical Activity Guidelines for Americans' from the US Department of Health and Human Services didn't significantly improve between 2007 and 2016 but time spent sitting increased.
Children from disadvantaged backgrounds do less vigorous physical activity
Children from disadvantaged backgrounds and certain ethnic minority backgrounds, including from Pakistani and Bangladeshi backgrounds, have lower levels of vigorous physical activity, according to researchers at the University of Cambridge.
Light, physical activity reduces brain aging
Incremental physical activity, even at light intensity, is associated with larger brain volume and healthy brain aging.
Decline in physical activity often starts as early as age 7
Overall physical activity starts to decline already around the age of school entry.
Is it ever too late for adults to benefit from physical activity?
It may never be too late for adults to become physically active and enjoy some health benefits.
Physical activity in the evening does not cause sleep problems
Contrary to popular belief, there is no reason to avoid exercising in the evening, an analysis of the scientific literature has revealed.
Genetic changes associated with physical activity reported
Machine learning used to improve understanding of sleep, physical (in)activity and their health consequences
New physical activity guidelines for Americans released
Updated physical activity guidelines released by theĀ U.S. Department of Health and Human Services (HHS) tell Americans to get moving, and for how long, with aerobic and muscle-strengthening activities.
More Physical Activity News and Physical Activity Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#538 Nobels and Astrophysics
This week we start with this year's physics Nobel Prize awarded to Jim Peebles, Michel Mayor, and Didier Queloz and finish with a discussion of the Nobel Prizes as a way to award and highlight important science. Are they still relevant? When science breakthroughs are built on the backs of hundreds -- and sometimes thousands -- of people's hard work, how do you pick just three to highlight? Join host Rachelle Saunders and astrophysicist, author, and science communicator Ethan Siegel for their chat about astrophysics and Nobel Prizes.