Recipe for happiness: 45 minutes' exercise 3 times a week
Exercise, especially cycling, has the best effect on reducing depression and anxiety by up to 40%
Just 45 minutes of exercise a day at least three times a week can improve your mental health by 40%.
A study of more than 1.2 million Americans, published in the medical journal The Lancet this week, also found cycling and team sports had the best effect on reducing people’s depression and anxiety ahead of running, swimming and walking.
Author Dr Adam Chekroud, from Yale University, says this is likely because those sports encourage socialising.
Yoga and Tai Chi also faired very well in lowering rates of depression.
The interviewers asked more than 1.2 million people over three years: “Thinking about your mental health, which includes stress, depression and problems with emotions, for how many days during the past 30 days was your mental health not good?”Those who exercised between three and five times a week were much less likely to have reported a day of bad mental health.
The study does not rule out using medication if a doctor has prescribed it for anxiety or depression.
Chekroud said: “In general, there have been studies showing that exercise plus antidepressants is more effective than antidepressants alone. People should not use exercise instead of other treatments for mental illness. It is a nice to have but other medication and therapy is a must-have.”
Chekroud said that because the study was so big and so many people did different kinds of exercises, they were able to “zoom in” and ask if the kind of exercise and time spent mattered.
It looks like those differences mattered. For example, people who exercised for about 45 minutes seemed to have better mental health than people who exercised for less than 30, or more than 60 minutes. A sweet spot for mental health, perhaps?”
“Something similar was happening with the number of times people exercised. People who exercised three to five times a week seemed to be feeling better than people who were outside that zone. The type of exercise people did seems important too. People doing team sports or cycling had much better mental health than other sports. But even just walking or doing household chores was better than nothing.”Compared to individuals with a normal weight, obese individuals had an approximately four percent worse mental health burden, it found.
“This is a huge study, confirming what we know about exercise’s mental health benefits. I am very excited about it,” said psychiatrist Dr Renata Schoeman, who is a member of the South African Society of Psychiatrists.
Schoeman said another study showed that exercise five times a week for 30 minutes could reduce anxiety and depression by 47%: “The key is regularity rather than doing one hike once a week for three hours.
“I have always had a realistic approach to helping patients. Medication is important, but it is never the only answer. In some cases therapy is indicated. A person then needs to address their stresses and then work towards a healthy lifestyle ensuring adequate sleep and regular exercise.”
She said the study showed some exercises were more effective than others in reducing depression.
One limitation of the Yale study was that it is based on self-reported amount of exercise and some people may over estimate or exaggerate how much they do. Authors suggested future studies could use data from wearable sensors such a fitbit as this gives a more accurate measure of the regularity, duration and intensity of exercise.