Physical activity may not reduce depression among teens

There is no association between physical activity (PA) and the development of depressive symptoms later on in adolescence, a study has found.

Physical activity has been cited as a way to reduce the risk of depression but the evidence is not clear-cut.

"Our findings do not eliminate the possibility that PA positively affects depressed mood in the general population; rather, we suggest that this effect may be small or non-existent during the period of adolescence," said the researchers.

"Although PA has numerous benefits to physical health in later life, such positive effects may not be expected on depressive outcomes during adolescence," they added.

The study involved 736 participants (average age 14.5 years) and was conducted from November 2005 to January 2010.

The authors used physical activity energy expenditure and moderate and vigorous physical activity measures.

They found no association between the levels of physical activity at 14 years of age and depressive outcomes at 17 years of age.

The study appeared in the journal JAMA Pediatrics.