October 6, 2026, 11:43 am | Read time: 4 minutes
How much teenagers move in their daily lives could play a role not only in their physical health. A large U.S. study examined how daily step counts relate to mental health, school grades, and brain structure.
More Movement Is Associated With Better Mental Health
Teenagers who took more steps in their daily lives showed fewer mental health issues on average a year later. The higher the step count, the more consistent this benefit was—the difference was most pronounced among teenagers with at least 12,000 steps per day compared to those with fewer than 5,000 steps.
Teenagers who took more steps per day had a slightly thicker cerebral cortex in two specific brain regions. These areas are important for movement and body perception, as well as for processing emotions and stimuli. The results also suggest that changes in one of these regions could explain a small part of the link between more movement and better mental health.
How the Study Was Conducted
Researchers from King’s College London and the University of Massachusetts Amherst analyzed data from 5,515 teenagers from 21 study centers in the U.S. The participants were on average just under 12 years old and wore an activity tracker on their wrist for three weeks to determine their average daily step count. At the same time, MRI scans were conducted to provide information about the structure of various brain regions.1
A year later, the researchers used a questionnaire to assess emotional problems, behavioral issues, and attention problems, among other things. They also recorded the participants’ school grades.
The researchers aimed to find out whether daily step counts were related to later mental health, academic performance, and brain structure. In their calculations, they considered factors such as age, gender, body mass index, parental education, and social and economic conditions.
The More Steps, the Better
Participants averaged about 9,600 steps per day, with most taking between 7,400 and 11,400 steps. For analysis, the researchers grouped the teenagers based on their daily step counts. Even teenagers with 5,000 to 7,499 steps had fewer mental health issues than those with fewer than 5,000 steps. As the step count increased, the difference became more pronounced, with the most significant difference at 12,000 steps per day or more.
However, the researchers did not find a specific step count at which the relationship became particularly clear or stopped increasing. Therefore, the study does not suggest a target value like 10,000 or 12,000 steps.
There was no clear pattern in school grades. Overall, more steps were not associated with better grades. Only teenagers with 10,000 to 11,999 steps performed better than those with fewer than 5,000 steps.
Overall, the researchers found few differences in the brain. Most of the brain regions studied showed no clear connection with daily step counts.
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Study Evaluation
The strengths of the study include the large number of participants and the measurement of steps with activity trackers instead of self-reports. The researchers also considered many factors that could influence the results. Additional calculations with different assumptions led to similar results.
However, the study also has limitations. Pedometers primarily capture walking and running, so other activities and sports may be less accurately recorded. Additionally, it was not distinguished whether the teenagers were active indoors or outdoors.
The information on mental health and school grades came from the teenagers or their parents, so they were not based on medical diagnoses or independently collected school data.
Furthermore, the teenagers studied generally came from more socially advantaged families and had fewer mental health issues than participants whose data were not included in the analysis. Therefore, the results may not be easily generalizable to all teenagers.
As is generally the case with observational studies, other unrecorded factors could have influenced the results. The reverse is also possible: mental health could influence how much teenagers move.
The authors reported no conflicts of interest. The study was funded by several research organizations, which, according to the study report, had no influence on the conduct, analysis, or publication.
What Previous Studies Show
The results align with previous research. In a British long-term study with about 4,250 teenagers, participants wore a movement sensor for a week at ages 12, 14, and 16.2 Those who engaged in more light activity, such as walking, had fewer depressive symptoms on average at age 18. With each additional hour of light activity per day, the values were about eight to eleven percent lower. It was also notable that teenagers spent more time sitting as they got older.
A similar pattern is seen in adults: An analysis of 33 studies with more than 96,000 participants found that people with at least 7,000 steps per day had fewer depressive symptoms than less active individuals.3 However, like the current study, these results are based on observational data and do not prove a causal relationship.