Relationship between physical activity and depression and anxiety symptoms: a population study.

BACKGROUND: There are few studies evaluating the association between practice of physical activity and mood in a population sample. This study evaluated the frequency of symptoms of depression and anxiety in the population of the city of Sao Paulo and their association with the report of practice of regular physical activity.
METHODS: This survey was conducted with the adult population of Sao Paulo between July and December of 2007. The sample was composed of 1042 volunteers (both genders) with a mean age of 41.9±14.4 years. The volunteers were evaluated using the Beck Depression Inventory, the Beck Anxiety Inventory, and two simple questions designed to evaluate and classify physical activity. Socioeconomic status was also determined according to Brazil's Economic Classification Criterion.
RESULTS: People who do not engage in physical activity are two times more likely to exhibit symptoms of depression (PR: 2.1) and anxiety (PR: 2.5) compared with those who regularly practice physical activity and a higher prevalence of symptoms for anxiety (9.8%) and depression (10.9%) was observed among those claiming to not practice regular physical activity and 63.2% related did not practice any physical activity regularly.
CONCLUSION: Altogether, these results suggest that people who do not practice physical activity have a higher chance of exhibiting symptoms of depression and anxiety when compared to those who perform physical activity regularly. In this sense, regular physical activity must be encouraged, and this incentive should be routine in both current and future public health policies. Although the methodology in the present study does not allow assigning a relation of cause and effect, we observed associations between symptoms of depression, anxiety and physical activity.