Road running 20:30 [1] 2.0 mi (10:15 / mi)
shoes: BA14
Drove down to the oldest public park in the US for a couple of easy laps. I paid careful attention to the HR display of my garmin, and when it topped 170 I paused to sanity-check it against my neck. Conclusion: bogus data on the device, and my Rating of Perceived Exertion correlates with my HR.
Then bought some bagels and back home.