20 Minutes of Daily Exercise May Decrease Depression Risk in Older Adults
People over 50 who exercise for at least 20 minutes five times a week may have a lower risk of depression than those who don’t, a new study has found.
The research, published earlier this month in JAMA Network Open, suggests older adults may see significant health benefits from moderate exercise, even if they don’t hit the target recommended by the World Health Organization (WHO) of getting in at least five 30-minute workouts each week.
“We were trying to figure out: What is the bare minimum dose of physical activity you need for depression?” Eamon Laird, PhD, a lifestyle health researcher at the University of Limerick and the first study author of the new paper, told Health.
“Currently, it’s 30 minutes per day, and that can be quite hard for people to do,' he said. 'That’s the reason we wanted to investigate this.”
Knowing the benefits of shorter workouts may help more people prioritize exercise, Susan Albers-Bowling, PsyD, a psychiatrist and psychologist at Cleveland Clinic, told Health.
“Exercise can be like a magic wand to your mental and physical health,” she said. “But although we know it is great for our mental health, a lot of people struggle to do it.'
The new findings suggest that benefits only go up when people over 50 exercise more than 20 minutes a day; the study authors wrote that the risk of depressive symptoms continued to decrease as time spent exercising increased.
The research team also noted that people with certain chronic diseases—such as diabetes, lung disease, osteoporosis, and liver disease, among others—may need to exercise more than people without those diseases to reap the same mental health benefits.
Below, experts explain the connection between movement and mental health, as well as how to figure out how much exercise is right for you.
Physical activity and mental health, go hand in hand.
Exercise can help you deal with stress, lessen feelings of depression, and improve your mood and emotional well-being, according to the National Institutes of Health (NIH).
The new study's research team used two different tools to determine whether participants were depressed.
The first is called the Center for Epidemiological Studies-Depression Scale (CES-D), a 20-item list that helps experts determine the severity of a person’s depression.
To complete the CES-D, participants report how frequently they’ve recently experienced certain symptoms or feelings related to mental health. For example: how many times during the past seven days did you feel fearful, lonely, and sad.
The second test the researchers used is called the Composite International Diagnostic Interview (CIDI); it is structured similarly to the CES-D and allows experts to determine whether a person is suffering from panic disorder, general anxiety disorder, or major depression.
The participants were also asked about how much exercise they got on average, per week. Their activity level was measured using a system called the metabolic equivalent of task (or MET), which helps experts determine how quickly a person burns calories while they’re active vs. resting.
The new study involved 4,016 participants, all of whom were enrolled in The Irish Longitudinal Study on Aging. The average age of the participants was 61, and 54.9% percent of them were women. The researchers collected data from the participants at five different points from October 2009 to December 2018, then analyzed it from June to August 2022.
The researchers determined that people over 50 without chronic conditions who practiced moderate exercise (such as brisk walking) for 100 minutes a week—which works out to five 20-minute workouts—had a 16% lower rate of depressive symptoms. People in this category were also 43% less likely to have experienced major depression.
By contrast, the WHO recommends that everyone ages 18 to 64 get a minimum of 150 minutes of moderate exercise—or five 30-minute workouts—each week.
Study participants who exceeded 100 minutes a week saw an even greater benefit to their mental health.
“The more [exercise] you did, the better,” Laird said.
People who got 120 minutes of exercise a day had a 23% lower rate of depressive symptoms and were 49% less likely to have experienced major depression.
It’s worth noting, the study authors wrote, that older adults who get a lot of exercise may also be more inclined to have other healthy habits, like eating balanced diets and prioritizing social engagements.
Therefore, it could be that multiple lifestyle choices, not just the amount of exercise they get, lower their risk of depression.
The researchers found that people with chronic illness were also less likely to experience depression if they exercised, though they may need more exercise to see the same benefits as people without chronic illness.
Though the new research is focused on adults over 50, the results are applicable to people of all ages, Albers-Bowling said. “You have to find the right dose for you.'
To do this, she recommended keeping a log of how much you exercise over a given period of time. Note what kind of exercise you do each day and how long you practice it. Additionally, she said, you should take notes about how you’re feeling each day.
This will help you make connections about how much exercise you need to feel your best. “Maybe one day you do 20 minutes, another day an hour. Ask yourself: Does it make a difference, doing an hour?” Albers-Bowling said.
It’s also helpful to remember that “exercise” comes in many different forms.
“Our initial cognitive stereotype is cardio, when you’re really sweating,” she said. “But walking your dog, going up the stairs vigorously, playing with your kids—any kind of movement” can help.
Some people may associate the word “exercise” with negative feelings, Albers-Bowling added.
If this is the case for you, try swapping it out.
“If you have a knee-jerk reaction to the word exercise, I often reframe it to ‘movement’ or ‘mindful movement,’” she said. “This can help you overcome that block and stop seeing exercise as a punishment, something you have to do to burn calories.
