The Importance of Exercise for Young Teens

Diabetes risk and adolescent insulin resistance most affected by exercise during early teen years

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Exercise is important for people of all ages, but when it comes to diabetes risk, staying active during the early teen years might have particularly big benefits.

A new study found that physical activity helped reduce insulin resistance — a diabetes risk factor — most strongly around age 13, but that this raised benefit was gone by age 16.

"Insulin resistance rises dramatically from age 9 to 13 years, then falls to the same extent until age 16. Our study found that physical activity reduced this early-teenage peak in insulin resistance but had no impact at age 16," explained lead study author Brad S. Metcalf, PhD, of the University of Exeter in the United Kingdom (UK), in a news release.

In insulin resistance, the body becomes less sensitive to the hormone insulin, which helps the body turn glucose, or sugar, into energy. The condition causes blood sugar levels to rise and is a risk factor for type 2 diabetes.

Dr. Metcalf and colleagues followed 300 children in Plymouth, UK, from ages 9 to 16. Data on the children was gathered each year, including blood sugar, insulin and blood pressure levels. Activity levels were measured using accelerometers to track the patients' movement for one week during the yearly follow-ups.

At ages 12 to 13, when insulin resistance usually peaks, the presence of the condition was 17 percent lower in the more active young teens, Dr. Metcalf and team found. However, this difference in insulin resistance among the more active teens dropped over the next three years and was gone by the time the teens were 16.

At 14 years old, the more active teens had a 14 percent lower rate of insulin resistance and an 8 percent lower rate at age 15, before the insulin resistance differences dropped off at age 16.

"We are not saying that 16-year-olds don't need to be physically active, there are other health benefits to be gained from being active at all ages," Dr. Metcalf said.

These findings may help guide efforts aimed at reducing this diabetes risk factor in young teens, Dr. Metcalf and team noted.

This study involved mostly white students — all from one location in England. Further research is needed to confirm these findings among more diverse patients.

This study was published online Aug. 5 in the journal Diabetologia.

A number of groups, such as the Bright Future Trust and the UK National Institute for Health Research, funded this study. Dr. Metcalf and team disclosed no conflicts of interest.


Review Date: 
August 5, 2015
Last Updated:
August 13, 2015