After three-plus weeks of being too sick to exercise, it is a HUGE relief to me to be back in the gym! Didn't do a ton today, I am going to be cautious re: lungs, but it was good...
10 mins. warmup at 5mph, then 1-1-2-2-3-3--3-3-2-2-1-1 alternating 6.5mph run, 3mph recovery (3 miles, 36 mins.)
10 mins. core