Temps below zero again this morning so waited until 11am to get out. Even then it was only 7 or 8 degrees but the air did seem a bit cleaner than yesterday. Ran up to the jack-rabbit and was hoping to get a 5K tempo run down river bottoms road.
Felt good the first mile when most of the downhill occurs and ran it in 6:28, even had momentary thoughts of trying for sub-20 for the 5K. But then something weird happened about 1/2 way through the 2nd mile. I'm sure it had something to do with the single digit temps and/or gunky air but I started feeling like my airways - nasal passage and throat - were swelling up so that I couldn't breath.
Start feeling light-headed, cold headache, and a feeling like being smothered and everything went very south at that point. Had to quit after 2 miles with 2nd mile coming in at 6:46. Thankfully after about 1 minute the feelings of being smothered went away and I finished out the run nice and easy. Dang stinkin' inversion anyway.