And the improvement continues for me. More it tonight for an experiment,
5 miles at 9:15 min miles. Steady at 135 bpm 71%
5 miles at 9:00 min miles. Steady at 140 bpm 73.5%
Thats go on my max from 2 years ago of about 190.
This shows to me that it works. Constinant 5 or 6 days running which is possible as you are not trashing the legs by running quick. When you add in the steady 80% run the improvement really starts,
I presume my improvements will slow down as this is 1 min miles over 2 months.