I haven’t done very much that is physically challenging since I was thrown off a horse as a youngster in Arizona. As for grueling, the second most was (mass) producing live television shows on a shoestring in the early days of Channel 13. But like Marlo, the most grueling and painful physical experiences I’ve ever had were related to grief over the deaths of loved ones. It was like being thrown off a horse only not being able to get back on the horse again for a long, long time.