So I guess you were on the treadmill. I recommend setting the incline at 2 to 3 percent, which seems to greatly reduced the pounding of 0%. I always used to do a lot of climb, often working up to 11% at 4 mph, which equates to running up the Auto Road on My Washington in under 2 hours. Uphill on a treadmill is much better for your knees than running flat. Keep up the good training.
Ya, I've always kept the incline up a bit, your daughter taught me that :)
I plan on doing more hill work than I have been, this week has just been a bit of a chill week.