Researchers at the University of Cambridge have found no evidence linking physical activity and development of depressive symptoms in adolescence.
One in every 10 people suffers from depression at least once during their lifetime. The mental illness affects physical health more than diabetes or arthritis. The onset of depression, one of the pressing global health concerns, is believed to occur in adolescence.
Preventive measures introduced during this period of life could prove beneficial and reduce emotional burden and financial costs. Depression is normally treated with antidepressants, psychotherapy, or both.
Previous studies have highlighted the importance of physical activity to fight depression.
For the study, the researchers observed 736 participants (average age 14.5 years) from November 2005 through January 2010. They used physical activity energy expenditure (PAEE) and moderate and vigorous physical activity (MVPA) measures. A self-reported questionnaire and interviews were conducted to determine mood symptoms.
The researchers found no relationship between physical activity levels at 14 years of age and depressive outcomes at 17 years of age.
"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 nonexistent during the period of adolescence. ... Our findings carry important public policy implications because they help to clarify the effect of PA on depressive symptoms in the general population. Although PA has numerous benefits to physical health in later life, such positive effects may not be expected on depressive outcomes during adolescence," Author Umar Toseeb said in a press release.
According to a recent University of Bern study, sports and physical activity are effective in treating depression as they trigger same neurophysiological changes as antidepressants. They help reduce activity of the stress hormone cortisol and induce an effect similar to psychotropic drugs.
"Unfortunately, the meta-analyses do not allow any conclusions as to how often and how long weekly sport should be pursued," Researcher Mirko Wegner said in a press release. "But one can see that sport and physical activity alleviate depression. For instance, we were also able to determine that the effectiveness of sport is greater with depressive disorders than with anxiety disorders."
