TUESDAY, Oct. 14 (HealthDay News) -- In adolescents, physical inactivity is associated with emotional and behavioral problems, suggests a Finnish study of more than 7,000 teenagers who took part in a survey that assessed their levels of physical activity and mental and emotional health.

Boys who reported less than one hour of moderate to vigorous physical activity a week had more symptoms of anxiety, withdrawal and depression than boys who were more active. Inactive girls had similar problems, and were more likely than inactive boys to also report sleep problems and rule-breaking behaviors.

Both inactive boys and girls were more likely than active peers to have social and attention problems.

"Adolescence is already a complicated and sometimes difficult stage of life -- emotionally, mentally and physically," study author Marko T. Kantomaa said in an American College of Sports Medicine news release.

"Compounding that with negative mental and emotional effects brought on by physical inactivity does not help young people ease into adulthood. Physical activity could be a highly effective and relatively easy way to help that transition and could, in addition, lead to establishment of lifelong healthy habits," Kantomaa said.

The researchers noted that a growing body of evidence suggests that an increase in physical activity helps reduce symptoms of depression and anxiety in both adolescents and adults.

"It seems that there is a psychological and physiological connection that, when operating together, help explain the beneficial effects of exercise on mental health," Kantomaa said.

The study was published in the October issue of Medicine & Science in Sports & Exercise.

More information

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