Brains and bodies, like muscles, need exercise
What do they say about muscles - "Use them or lose them"?
Seems to me that is true of bodies, as well. No exercise and they get out of shape.
And true of brains - keeping them up to speed and active delays deterioration, it seems to me. Slothful brains get sloppy from underuse, don't you think?
Good wishes for success in preserving your vibrant pursuit of many activities, interests - and new friends (to replace the ones that you lose through relocation or death.