Even Light Exercise Prevents Future Depressions
A 2017 article in The American Journal of Psychiatry suggests that regular leisure-time exercise of any intensity can protect against future depressions.
The study by Samuel B. Harvey and colleagues followed a group of 33,908 healthy adults for 11 years. The researchers found a link between regular leisure-time exercise and reduced incidence of future depression (but not anxiety). This link occurred regardless of the intensity of the exercise, and most of the effect occurred at low levels of exercise. Analysis suggested that 12% of future cases of depression could be prevented if all participants fit one hour of physical activity into their week.
A small part of the benefit came from the social and physical health benefits of exercise.
Harvey and colleagues suggested that from a public health perspective, increasing population levels of exercise modestly could lead to a substantial decrease in depressions.
Editor’s Note: Alongside maintenance treatment, in the form of antidepressants for unipolar depression or mood stabilizers and atypical antipsychotics for bipolar disorder, exercise could provide some benefits in preventing future depressions.
Inactivity in Young Adulthood May Worsen Cognition Later in Life
The couch potato lifestyle common in the US may have consequences later, in the form of deficits in memory, executive functioning (including planning and execution) and processing speed.
At the 2015 Alzheimer’s Association International Conference, researcher Kristine Yaffe and colleagues reported that low levels of physical activity and high rates of television viewing in young adulthood may reduce cognitive capabilities in midlife.
The Centers for Disease Control report that less than 50% of adults aged 18–64 get the recommended minimum of physical activity each week. The guidelines recommend at least 150 minutes of moderate intensity aerobic activity (such as walking briskly) and two or more days of muscle-strengthening activities that work all major muscle groups.
Yaffe says that physical activity can protect against cognitive decline or dementia later on.
Participants in the long-term study who reported burning fewer than 300 calories per 50-minute session three times per week during two-thirds of their followup visits had worse cognition at year 25 than those participants who were more active. Those who watched more than four hours of television per day also had reduced cognition in midlife.
Yaffe stresses that exercising regularly is not just important in keeping weight down and protecting the heart, but also in protecting the brain. Regular physical activity may even prevent illnesses such as Alzheimer’s disease.
