Uphill fast-walk intervals

8 x 1/10 mile uphill on Cowles Mountain - 15% grade. Average uphill time was 88 seconds. Walk back down - approx. 2 minutes. Average HR for uphills = 145. Max HR 167. It's kind of a drag doing "fast-walk intervals" because when I reach a certain speed, I want to break into a jog. Life's tough, eh?