Seven-Day Pedometer-Assessed Step Counts and Brain Volume: A Population-Based Observational Study

Area of Science:

• Neuroscience
• Gerontology
• Public Health

Background:

• Brain volume (BV) is a key indicator of brain health and cognitive function.
• Physical activity, such as daily step counts, is increasingly recognized for its potential impact on brain structure.

Purpose of the Study:

• To examine the relationship between daily step counts and brain volumes in Japanese men aged 40-79.
• To investigate associations with global brain volume and specific cognition-related brain regions.

Main Methods:

• Analysis of data from 680 cognitively intact Japanese men (Shiga Epidemiological Study of Subclinical Atherosclerosis).
• Multivariable linear regression used to assess cross-sectional associations between 7-day step counts and brain volumes.
• Participants stratified into age groups: <60 years and ≥60 years.

Main Results:

• In men aged ≥60 years, higher step counts (per 1000 steps) were associated with increased total brain volume (β = 1.42, P = .022).
• Step counts correlated with prefrontal cortex volumes (P < .05) and marginally with the left entorhinal cortex (P = .05) in older adults.
• No significant associations were found in younger adults (<60 years) or with other brain regions (hippocampus, parahippocampal, cingulum, cerebellum).

Conclusions:

• A positive association exists between daily step counts and brain volumes, including the prefrontal cortex and left entorhinal cortex, in healthy older Japanese men.
• These findings suggest that physical activity, measured by step counts, may play a role in maintaining brain structure in aging individuals.