Study links sleep, activity to middle‑age mental health

University of Oulu researchers said a new study found that middle-aged adults who spent more of their day in moderate-to-vigorous physical activity and got enough sleep reported fewer symptoms of depression and anxiety. The findings were based on participants assessed at age 46 over a two-week period, with movement and sedentary time tracked and mental health measured with standard questionnaires. The study was published in the journal *Depression and Anxiety*, according to the university and a June 1 Medical Xpress report. ### What exactly did the researchers measure? The study tracked sleep, sedentary behavior, light physical activity and moderate-to-vigorous physical activity as parts of a 24-hour cycle, the University of Oulu said. Researchers then examined how differences in that daily time balance were associated with symptoms of depression and anxiety in middle age. Participants were monitored over a two-week period at age 46, and depression and anxiety were assessed using three symptom measures, according to the Medical Xpress report summarized from the university release. (medicalxpress.com) The report said the findings were consistent across all of the symptom measures used. ### How much activity was linked to better mental health? A 30-minute change in daily routine was associated with measurable differences, the researchers said. (medicalxpress.com) When 30 minutes of sedentary time was replaced with moderate-to-vigorous physical activity, depressive symptoms were 9% lower and anxiety symptoms were about 5% lower. Maisa Niemelä, an adjunct professor at the University of Oulu, said the findings pointed to intensity rather than movement alone. “The findings suggest that, from a mental health perspective, the intensity of physical activity is key,” Niemelä said, adding that moderate-to-vigorous activity is intense enough to leave a person slightly out of breath. (medicalxpress.com) ### Did light activity help too? (medicalxpress.com) Light activity, such as leisurely walking, was associated with smaller benefits than moderate-to-vigorous activity, according to the study summary. The researchers said simply increasing physical activity was not enough on its own if the added movement stayed at low intensity. A broader 2023 umbrella review in the *British Journal of Sports Medicine* also found physical activity was associated with reduced symptoms of depression and anxiety across adult populations, and said higher-intensity activity was linked to greater improvements. (medicalxpress.com) That review covered 97 systematic reviews and 1,039 trials. ### Where did sleep fit into the picture? Sleep was also independently linked to better mental health in the study, the researchers said. (medicalxpress.com) Participants reported sleeping an average of 7 hours and 30 minutes per night, and sleeping 5 to 30 minutes less was associated with a slight increase in depression and anxiety symptoms. Clarence Tan, a doctoral researcher at the University of Oulu, said the findings suggested physical activity should not come at the expense of sleep. “Getting enough sleep and increasing moderate-to-vigorous physical activity is an ideal lifestyle change for supporting mental health in middle age,” Tan said. (bjsm.bmj.com) ### What should readers be careful not to overread? (medicalxpress.com) The findings were reported as associations, not proof that exercise or sleep directly caused changes in mental health. The university and Medical Xpress report described links between daily time use and symptom levels, rather than the results of a randomized treatment trial. The next place to look for more detail is the full paper in *Depression and Anxiety*, where the underlying methods, questionnaires and statistical analysis are documented by the study authors. (oulu.fi) (medicalxpress.com)