no idea if this is a "thing" ... but, whenever the bottom of my feet get jacked up (plantar fasciae sore etc), I have this nagging thought to "walk on rocks". It actually seems to help. It can get quite painful if I hit the "right combo of rocks", digging in to various spots within the sole of my foot. Some of the positions feel really good, some feel painful & then good, etc.. It's almost like some kind of deep tissue work. The different rock positions also stretch my toes/forefoot in different ways too.
I have pebbles in the back yard, to fill in certain spots. So I can just walk around (slowly) for 10 minutes or so, pausing in certain spots.
dno. feels good.
hehe.