We all know that an inactive lifestyle contributes largely to a plethora of chronic diseases such as obesity, diabetes, heart disease, osteoporosis and more. We also know the importance of exercise when it comes to weight loss. But how often do we consider the contribution of physical exercise to our mental health?
It is not new information that a single bout of exercise can lift the blues and improve mood. It can take as little as ten minutes and even is helpful for people suffering from major depression. Studies have in fact shown that exercise is comparable to antidepressant medication for relieving depression! Exercise also appears to be as good as existing pharmacological interventions for other mental health conditions such as dementia, anxiety and even reduces cognitive issues in schizophrenia. A recent study of more than 10,000 individuals revealed that not only are people who are more physically active happier, individuals are happier in the moments when they are more physically active.
Most of us can also attest in our own lives that a sunny walk or trip to the gym improves our moods in the short term.
But how does this actually happen?
Exercise stimulates the body to produce endorphins and enkephalins, the body’s natural feel good hormones. Regular exercise increases the volume of certain brain regions- in part through better blood supply that improves neuronal health by improving the delivery of oxygen and nutrients as well as through an increase in neurotrophic factors and neurohormones that support neuron signalling, growth and connections.
The hippocampus, a region of the brain involved in memory, emotion regulation and learning, is of paramount importance for mental health. Evidence is accumulating that demonstrates that numerous mental health conditions are associated with reduced neurogenesis in the hippocampus. The evidence is particularly strong for depression. Animal studies have shown that exercise leads to the creation of new hippocampal neurons (neurogenesis).
So, I’m convinced, but how much exercise?
Psychiatrist Madhukar Trivedi, states that at least three sessions per week for 45-60 minutes per session, of aerobic exercise or resistance training can assist in the treatment of even chronic depression. Effects tend to be noticed after about four weeks which, incidentally, is how long neurogenesis takes. Training should be continued for 10-12 weeks for the greatest anti-depressant effect. Exercise levels below these amounts are still beneficial and may have more short-term effects for depressive disorder. They also come with a host of other positive side effects such as weight loss, increased energy, better skin and improved physical health. Even small increases in exercise levels can 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 when we first begin.
So where to from here?
Start with 10 minutes of physical activity per day as a natural mood booster. As we reap its rewards for both our physical health and mental health, exercise will become not just part of our routine, but it will become our lifeline.
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