There have been numerous studies that suggest physical activity reduces depressive symptoms, but these studies have been subject to many limitations, according to the study authors of a new study. The study, led by Dr. Snehal Pinto Pereira of the Institute of Child Health at University College London (UCL) in the UK, found that engaging in physical activity three times a week can prevent or reduce symptoms of depression.
“Most studies have been cross-sectional, from which the direction of the relationship cannot be disentangled, and from the few prospective studies, findings have been inconsistent,” the researchers explain. They add, “Also at the general population level, people with depressive symptoms may be less likely to engage in activity than their counterparts; however, this potential explanation for observed cross-sectional associations has received little attention.”
For the study, researchers analyzed 11,135 individuals born in 1958, following them until the age of 50. At ages 23, 33, 42 and 50, they self-reported physical activity level and depression symptoms were assessed through their responses to the Malaise Inventory – a questionnaire that assesses psychological distress. The researchers found that across all age groups, the more physical activity an individual engaged in each week, the lower the risk of depression. Engaging in physical activity 0-3 times a week reduced the risk by 19 percent and every additional physical activity session reduced the risk by another 6 percent.
Senior study author Christine Power, professor of epidemiology and public health at the Institute of Child Health at UCL, says, “If everyone was physically active at least three times a week we would expect to see a drop in depression risk, not to mention the benefits for physical health, as pointed out by other research, including reduced obesity, heart disease and diabetes risk.”