I think you'd have to be more specific than "exercise" as heavy resistance training activates mTor and not AMPK. If memory serves they are mutually exclusive and cannot be activated simultaneously. Low intensity exercise, such as walking and easy running stimulates AMPK - as does extended fasting.

During covid, my 70 y.o. mom started going on long walks (like five miles) and fasting. Mostly out of boredom, she self-isolated.

I noticed that she is a lot sharper now. Previously, she would forget something in a conversation or ask twice. Now she is absolutely here and if we for example discuss some video, she mentions details that I overlooked.

That was quite a change.

Some really smart researcher applied clinical trial data to make a calculator to guesstimate what different intensities and durations of exercise will activate AMPK to various levels:

https://rothschild.shinyapps.io/AMPK_dashboard/

Fun to play with.

How long is extended?