A large US study reveals that teenagers who walk 12,000 or more steps daily are less likely to experience emotional and behavioural difficulties a year later, with brain scans indicating possible biological benefits of increased movement.
A large US study has found that teenagers who walk more each day tend to have better mental health a year later, with the strongest benefits seen in those taking 12,000 steps or more. The findings, published in JAMA Network Open and reported by Neuroscience News, suggest that the relationship between movement and well-being is gradual rather than fixed, with no clear point at which the advantages stop increasing.
Researchers at King’s College London and the University of Massachusetts Amherst analysed data from 5,515 adolescents in the Adolescent Brain Cognitive Development Study, a long-running project spanning 21 research sites in the United States. The participants, most of them aged about 12, wore Fitbit devices for three weeks to record their daily step counts. Their mental health was then assessed a year later using the Child Behaviour Checklist, a standard tool that measures symptoms such as anxiety, low mood and behaviour problems.
The pattern was striking. Young people who averaged fewer than 5,000 steps a day had the highest levels of emotional and behavioural difficulties, while those around 8,000 steps a day fared better. The fewest problems were seen among adolescents who reached 12,000 steps or more. The researchers also found that each additional 1,000 to 2,000 steps was linked with measurable gains, which suggests that modest increases in everyday movement may still matter. Importantly, the study found no link between step count and school performance.
Brain scans added another layer to the picture. Teenagers with higher step counts showed slightly thicker cortex in regions involved in movement and emotional regulation, including areas of the brain associated with motor control and the anterior cingulate, which helps manage attention and emotions. According to the JAMA Network Open paper, those structural differences partly explained the connection between greater activity and fewer later mental health problems. The researchers said this points to a possible biological pathway, though the study was observational and cannot prove that walking more directly causes better mental health.
The findings fit a wider public health concern as children and adolescents spend more time indoors and less time being active. Amanda Paluch, a co-author from the University of Massachusetts Amherst, said the results show young people do not need to be elite athletes to benefit, and that realistic steps such as walking to school or active play can add up. The researchers said the work adds to evidence that small, accessible habits may support both brain development and emotional health during a sensitive stage of adolescence.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
