A few weeks ago in this video, From Osteopenia to Ninja Warrior at 73!! Ginny's Unique Formula for Aging Strong! I came across the concept of a Dead Hang where you hold onto a bar above your head and just support your body weight. It apparently:

is good for the brain, decompresses the spine and improves grip strength.

My first few attempts went nowhere but now I can support my weight for about 10 seconds. I like the spinal stretch.