An hour of exercise per week can help prevent depression, a study has found
Scientists monitored levels of exercise and symptoms of depression and anxiety in almost 34,000 Norwegian adults over 11 years.
They found that 12% of cases of depression could have been prevented by engaging in just an hour of physical activity each week.
Lead researcher Dr Samuel Harvey, from the Black Dog Institute at the University of New South Wales, Australia, said: “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.
“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 team analysed data from the Health Study of Nord-Trondelag County, one of the largest health surveys ever undertaken, conducted in Norway between January 1984 and June 1997.
Results showed that people who reported doing no exercise at all at the start of the study were 44% more likely to develop depression than those exercising one to two hours per week.
The benefits did not extend to protecting against anxiety, said the authors, whose findings appear in the American Journal of Psychiatry.