RIP Grete Waitz
I had the good fortune of actually lining up next to her a couple of times at the 10K Zoo Run in Denver in the mid-1980s. She'd travel out to Colorado in the fall back then for some altitude training. She'd say, "Oh, I'm just jogging today," and would still run 35 minutes, and place near the top of a national class field.
She was totally cool and gracious.