reviews. PHYSICAL ACTIVITY AND ANXIETY The US Department of Health and Human Services Report conclusion was that the evidence from a small number of nationally representative and population-based and prospective cohort studies supported regular physical activity as protective against the onset of anxiety disorders and symptoms. The report cited an Australian prospective population-based study which found that the odds of developing any anxiety disorder were reduced by an average of 53% among those who reported more than 3 hours per week of vigorous physical activity compared with those reporting no activity. The effect was, however, not statistically significant, in part due to the small number of participants who developed an anxiety disorder. Results were also cited from a German study that indicated statistically significant 48% lower odds of developing any anxiety disorder among regularly active young adults compared with those reporting no activity. The US Report concluded that evidence from RCTs indicated that participation in physical activity programs reduces anxiety symptoms in healthy adults. The effect of exercise compared to control conditions was 0.40SD (40 comparisons; 95% CI 0.27-0.53). Just over half the trials used moderate to vigorous intensity activity with a frequency of 3 or more days per week. The magnitude of anxiety reduction was weakly correlated with the magnitude of fitness increase (r=0.24) after adjusting for sample size. There was an absence of evidence from prospective cohort studies or RCTs that examined whether effects varied by type, timing or intensity of physical activity. We identified one additional review for this report. Conn et al. integrated data from 19 reports (published and unpublished studies 1983-2008) and 3,289 participants to conduct a meta-analysis on the relationship between physical activity and anxiety outcomes in healthy adults. Studies that included some form of psychological treatment were
reviews. PHYSICAL ACTIVITY AND ANXIETY The US Department of Health and Human Services Report conclusion was that the evidence from a small number of nationally representative and population-based and prospective cohort studies supported regular physical activity as protective against the onset of anxiety disorders and symptoms. The report cited an Australian prospective population-based study which found that the odds of developing any anxiety disorder were reduced by an average of 53% among those who reported more than 3 hours per week of vigorous physical activity compared with those reporting no activity. The effect was, however, not statistically significant, in part due to the small number of participants who developed an anxiety disorder. Results were also cited from a German study that indicated statistically significant 48% lower odds of developing any anxiety disorder among regularly active young adults compared with those reporting no activity. The US Report concluded that evidence from RCTs indicated that participation in physical activity programs reduces anxiety symptoms in healthy adults. The effect of exercise compared to control conditions was 0.40SD (40 comparisons; 95% CI 0.27-0.53). Just over half the trials used moderate to vigorous intensity activity with a frequency of 3 or more days per week. The magnitude of anxiety reduction was weakly correlated with the magnitude of fitness increase (r=0.24) after adjusting for sample size. There was an absence of evidence from prospective cohort studies or RCTs that examined whether effects varied by type, timing or intensity of physical activity. We identified one additional review for this report. Conn et al. integrated data from 19 reports (published and unpublished studies 1983-2008) and 3,289 participants to conduct a meta-analysis on the relationship between physical activity and anxiety outcomes in healthy adults. Studies that included some form of psychological treatment were