400m run at 5km pace then walk 200m 10x. This was hard and with the weather and the icy ground it made these intervals even more challenging. Keeping the pace even through all 10 intervals was the test and I felt at least through the first 7, the last 3 was really a challenge but I felt I was still on pace. Too bad I didn't program the workout, but I at least know I got the workout done.