Thanks Scott! Everyone who has followed your work has tremendous respect for you and your experience and wisdom. I will to continue to experiment. I think that is what we are all doing to a certain extent. Until this race, I am going to stick with 1 uphill z3 w/o, 1 z4 uphill sprint w/o, 1 z1 long run, and the rest 45-90 min z1 recovery days. I have found that 4-6 x 20-30 sec wind sprints (maybe 80-85%effort) at the end of my Recovery/Z1 days feel good and keep the muscles sharp. If I’m too tired, then I just don’t do them. Best of luck with this new venture!!