I’ve been 70 for a couple of weeks now. The downsides include the old man’s existential confrontation with time and inevitability, disappearing short-term memory, and the onset of Raynaud’s disease, which makes my fingers turn almost comically white and go numb when the weather turns even a little chilly. The upsides are lots of love, a spectacular family, both nuclear and extended, great friends, freedom to travel, and a general level of physical health and fitness that astonishes and delights. Post-Mayo, I’ve changed my diet and lost vast blobs of flab.The gym has made me stronger and more flexible than I’ve ever felt. And the wonderful rhythmic swing of running, my great joy, goes well when the weather permits. According to my cool Garmin gizmo, my resting heart-rate these days is in the low 40s. I’ll take it.