Table 2.

Unique proportion of variance (R²) accounted for by age, exercise engagement, and the interaction of age and exercise engagement.

Brain Structure	Age	Exercise Engagement	Age × Exercise Engagement
Global Volumes
Cerebral Gray Matter	.31***	.05	.01
Cerebral White Matter	.41***	.01	.00
Regional Cortical Volumes
Dorsal/Ventral Lateral Prefrontal Cortex	.19***	.02	.00
Superior Frontal Cortex	.23***	.07*	.01
Lateral Parietal Cortex	.34***	.01	.01
Superior Temporal Cortex	.34***	.02	.01
Pericalcarine Cortex	.04	.07*	.02
Regional Subcortical Volumes
Medial Temporal Lobe	.24***	.00	.07*
Hippocampus	.34***	.01	.02
Amygdala	.20***	.00	.05
Parahippocampus	.02	.01	.06
Neostriatal Nuclei	.16**	.02	.01

^*Note: p ≤ .05;

^**p ≤ .01;

^***p ≤ .001