There's also plenty of mech tales where the mech pilots need to spend as much time out of the suits making sure their muscles (and/or mental health) are in good strength precisely because the mechs are a "force multiplier" and are only as strong as their pilot. That's a somewhat common thread in such worlds.

I like the electric bike as a metaphor. You can go further faster, but you quickly find yourself miles from home and out of juice, and you ain't in shape enough to get that heavy bugger back.