Rates of depression and anxiety are at their highest recorded levels in countries as diverse as India, China, the U.S., and the UK. Undoubtedly, many aspects of “modern life” — increasing social isolation, poor diets, a focus on money and image — contribute to this state. However, inactivity is another key factor.
Most of us find that a sunny walk or trip to the gym improves our mood in the short term. Exercise is well known to stimulate the body to produce endorphins and enkephalins, the body’s natural feel-good hormones which can make problems seem more manageable. The simple act of focusing on exercise can give us a break from current concerns and damaging self-talk. Further, depending on the activity, people may benefit from calming exercises, be energized, and get outside or interact with others, all of which are known to improve mood and general health.
However, the idea that physical exercise might do something really fundamental for mental health is less immediately obvious — especially given the Western distinction between “mind” and “body” that implies mental and physical health can be separated.
Of critical importance for mental health is the hippocampus — an area of the brain involved in memory, emotion regulation, and learning. Studies in other animals show convincingly that exercise leads to the creation of new hippocampal neurons (neurogenesis), with preliminary evidence suggesting this is also true in humans.
What does this all mean? Theories suggest that newborn hippocampal neurons are likely to be particularly important for storing new memories and keeping old and new memories separate and distinct. Thus, neurogenesis allows a healthy level of flexibility in the use of existing memories, and in the flexible processing of new information.
Much mental ill health is characterized by a cognitive inflexibility that keeps us repeating unhelpful behaviors, restricts our ability to process or even acknowledge new information, and reduces our ability to use what we already know to see new solutions or to change. It is therefore plausible that exercise leads to better mental health in general, through its effects on systems that increase the capacity for mental flexibility.
With today’s trend for “10 seconds to a new you”-type solutions, this may seem like a lot of exercise, but no worthwhile mental health fix comes for free. Exercise levels below these recommended amounts are still beneficial, and of course the side effects (weight loss, increased energy, better skin, improved physical health, etc.) are pretty palatable.
The brain actually has a neat trick to get us back on track. As outlined by Psychology Today blogger Christopher Bergland, even small improvements in exercise levels or diet create a positive upward spiral that increases the sensitivity of the dopamine receptors that signal reward, so that exercise will eventually become rewarding, even if that seems unimaginable at the outset.