Public Health

Area of Science:

• Neuroscience
• Human Brain Anatomy
• Exercise Physiology

Background:

• Previous research suggests a link between physical activity and brain grey matter volume.
• The influence of sex on this association remains unclear and debated.

Purpose of the Study:

• To investigate if physical activity is associated with grey matter volumes in the hippocampus and dorsolateral prefrontal cortex (dlPFC).
• To determine if sex moderates the relationship between physical activity and these brain regions.

Main Methods:

• Examined data from 1,809 participants across five European cohorts (Lifebrain consortium).
• Utilized linear models and random-effects meta-analysis to assess associations and sex interactions.
• Focused on self-reported physical activity and regional grey matter volumes.

Main Results:

• Found no significant relationship between physical activity and hippocampal or dlPFC volumes.
• No evidence of sex as a moderator in the association between physical activity and grey matter volumes.

Conclusions:

• Null findings suggest self-report physical activity questionnaires may not be sensitive enough for detecting modest brain-behavior associations.
• Reliance on self-report data is suboptimal for nuanced brain-behavior analyses.
• Further research may require more objective measures of physical activity.