Thanks Layla, yeah, got off a phone call with a colleague south of Chicago; really cold! Cars not starting, runs from car to office/shops, etc. She even said she will go out and start the car periodically during the day at the office; she too mentioned a let up this weekend. I don't "think" the half-mile is pushing too much; seemed just about right as there are some elevation changes and if I break it up talking to neighbors out and about, should be manageable--just need to build up over time. Feel pretty good after five hours, no nagging pain like I overdid things, so will keep things moderate and watched closely. Stay warm!