Exercise can boost your mental and cognitive health — but not all forms and intensity of exercise affect the brain equally. In fact, according to a new Dartmouth study, the effects of exercise are even more subtle. It found that a certain intensity of exercise over a long period of time correlated with different aspects of memory and mental health. The results were recently published in the journal Scientific Reports and provide insight into how to improve your workout.
“Mental health and memory are fundamental to nearly everything we do in our daily lives,” says Jeremy Manning, lead author. He is an assistant professor of psychological and brain sciences at Dartmouth. “Our study attempts to build a foundation for understanding how different physical exercise intensity affects different aspects of mental and cognitive health.”
For the study, researchers enrolled 113 Fitbit users. They were asked to take a series of memory tests, answer some questions about their mental health, and share their fitness data from the previous year. The scientists expected that more active individuals would have better memory performance and better mental health, but the results were more accurate. Participants who tended to exercise at low intensity performed better on some memory tasks, while those who exercised at high intensity performed better on other memory tasks. People who were more active also reported higher stress levels, while those who exercised regularly at a lower intensity showed lower rates of depression and anxiety.
Previous research has typically focused on the effects of exercise on memory over a relatively short period of time, such as over several days or weeks. However, the Dartmouth scientists wanted to analyze the effects over a much longer timescale. The data collected included average heart rates, number of daily steps, and the amount of time spent exercising in different “heart rate zones” as defined by FitBit (rest, out of range, fat burn, or cardio). , or peak), and other information collected during an entire calendar year. Study participants were recruited online from Amazon’s Mechanical Turk, a collective workforce.
There were four types of memory tasks used in the study, which were designed to explore different aspects of participants’ abilities over different time periods. Two sets of tasks focused on testing “episodic” memory – the same type of memory used to remember autobiographical events, as you did yesterday. Another set of tasks was developed to test “spatial” memory – the same type of memory used to remember locations, such as where you parked your car. The final set of tasks aimed to test “associative” memory – the ability to remember connections between concepts or other memories.
Participants who had been more active during the previous year tended to show better memory performance overall. However, the specific areas of improvement depend on the types of activity that people do. The researchers discovered that participants who often exercised at moderate intensity tended to perform better on episodic memory tasks, while those who often exercised at high intensity performed better on spatial memory tasks. Sedentary participants who rarely exercised typically performed worse on spatial memory tasks.
The research team also identified links between participants’ mental health and memory performance. Participants with self-reported anxiety or depression tended to perform better on spatial and associative memory tasks. People with self-reported bipolar disorder tend to perform better on episodic memory tasks. Those who reported higher levels of stress tended to perform worse on associative memory tasks.
All data and codes were provided free of charge by the research team at github For anyone who wants to explore or better understand the data set.
“When it comes to physical activity, memory, and mental health, there’s a really complex dynamic that can’t be summed up in single sentences like ‘walking improves your memory’ or ‘stress hurts your memory,'” Manning says. of mental health affects every aspect of memory differently.”
As more research is conducted, the researchers say their findings could have some exciting applications. “For example, to help students prepare for an exam or reduce their depressive symptoms, specific exercise regimens can be designed to help improve their cognitive performance and mental health,” Manning says.
Reference: “Fitness tracking reveals task-specific associations between memory, mental health, and physical activity” by Jeremy R. Manning, Gina M. Notaro, Esmee Chen, and Paxton C. Fitzpatrick, August 15, 2022, Scientific Reports.
DOI: 10.1038 / s41598-022-17781-0