Depression is the leading cause of disability in this nation, and it’s often associated with anxiety. To counter depression, the World Health Organization recommends participation in exercise activities on 2 or more days each week that provides at least 150 minutes of moderate-intensity physical activity, including 75 minutes of vigorous-intensity physical activity combined with resistance training. However, only 23% or less of US adults meet such recommendations. A recent study examined the association between meeting those recommendations for exercise and symptoms of depression and anxiety. The researchers found that there is lower depression/anxiety risk in those meeting those activity recommendations. They also determined that the magnitude of risk reduction is most significant in those coming the closest or exceeding these recommendations.
This may be compared with other studies in which both aerobic physical activity and resistance training are effective for reducing symptoms of depression or anxiety. The authors of the current study note that there may be a synergistic relationship between aerobic activity and resistance training, and the benefit may be attributable to overall increased levels of exercise activity in a dose-response relationship.
One previous systematic review of 15 prospective studies including more than 2 million person-years also showed an inverse association between physical activity and depression, with greater differences in risk at lower exercise levels. Adults meeting physical activity recommendations (equivalent to 2.5 h/wk of brisk walking) had lower risk of depression, compared with adults reporting no physical activity. Therefore, in this study, relatively small doses of physical activity were associated with substantially lower risks of depression.
Although virtually all levels of exercise are beneficial, medical care providers can be most effective when encouraging depressed patients to increase specifically the duration and intensity of physical exercise that includes resistance training, This research also had implications for patients recovering from major depression, of whom 50% or more will experience subsequent episodes. Typically, when previously depressed patients move into a recovery-maintenance phase, they are primarily encouraged to monitor symptoms and seek treatment if symptoms reemerge. Recovered patients should continue an active lifestyle on a regular basis to reduce the likelihood of subsequent depression.
Health practitioners are most effective when encouraging any increase in physical activity to improve both physical and mental health: In general, the more exercise, the better. Interestingly, regarding anti-depressive results, exercise therapy may equal—or even exceed—those benefits obtained from the use of all those ubiquitous anti-depressive drugs on TV ads, at least in those suffering from mild or moderate depression. It’s unlikely that we would ever see a direct scientific comparison study between drugs and exercise. This raises the intriguing question: If economic incentives behind exercise promotion were equal to those expended on antidepressant drug promotion, which one would be the winner?