Definitely things that ground me. Depending on how the body memory is effecting me, I like to go to grounding activities that use my body in a different way.
Taking the dog for a vigorous walk, with a carefully selected playlist, getting into the garden (even if it's just pulling weeds, that one works a treat for reason), or cleaning something (kitchen cupboards are my go-to).
If it's just too overwhelming? And I'm too distressed? Then I also go with the medication and bomb myself out option. If I can, I try and make sure I get into something comfortable, and put on some relaxation music softly in the background, so that I can really amp up the feeling that I'm at least trying to be gentle with myself.