Published in the American Journal of Psychiatry, the largest and most extensive study of its kind found that even one hour of working out – whether it's a gentle stroll or slogging it out at F45 – each week can have benefits for mental health.
Researchers analysed 33,908 Norwegian adults over a period of 11 years, monitoring their exercise habits and symptoms of depression and anxiety.
Their results indicated that 12 percent of depression cases could have been prevented if participants engaged in just one hour of physical activity each week. Further, participants who said they didn't exercise at the study’s start were 44% more likely to become depressed, compared to those who exercised at least 1 to 2 hours a week.
However, the benefits of a regular exercise didn’t have any effect in protecting against anxiety.
"We've known for some time that exercise has a role to play in treating symptoms of depression, but this is the first time we have been able to quantify the preventative potential of physical activity in terms of reducing future levels of depression," said lead author Associate Professor Samuel Harvey from Black Dog Institute and UNSW.
"These findings are exciting because they show that even relatively small amounts of exercise – from one hour per week – can deliver significant protection against depression.
"We are still trying to determine exactly why exercise can have this protective effect, but we believe it is from the combined impact of the various physical and social benefits of physical activity.
"These results highlight the great potential to integrate exercise into individual mental health plans and broader public health campaigns. If we can find ways to increase the population's level of physical activity even by a small amount, then this is likely to bring substantial physical and mental health benefits."
The Jean Hailes Women’s Health 2017 survey of over 10,000 Australian women found that a significant number weren’t achieving the recommended amount of physical activity, with 60% of respondents admitting they weren't undertaking at least 2.5 hours of moderate exercise each week. The survey also revealed that 40% of Aussie women have been professionally diagnosed with depression or anxiety.
While it's important to ensure you're regularly exercising, if you think you might be suffering from depression or anxiety speak to a medical professional immediately or contact a support hotline:
Lifeline on 13 11 14
SANE on 1800 187 263
Beyond Blue on 1300 22 4636