I was doing VO2 sessions on Tuesdays for a while and would do 3' intervals bookended on 3x5' as my protocol. The 3' were up hills, and were hugely different in their power lol . For the second (and last) 3' interval I barely squeak out 120%, but the first is like 127% or more lol.
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"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste