When I do an interval session (in this case 5x1km with 1km jogged warm-up and recoveries). My performance condition usually starts off negative, in this case -7, but once I start the first interval, it rapidly climbs to +5, and thereafter has slight dips and rises slightly lagging after the recoveries, as shown below:
I would have thought my actual performance condition (ability to run) has not changed from the start of the run to the end of the first interval, so why has my estimated performance condition changed so much?
Is this because when I am jogging my running economy is very poor, so I am running slowly for a zone 2 heart rate, but when I am really running, my running economy is better so my pace is better for the heart rate (in this case zone 4 and 5).
I am wondering whether my zone 2 jogging is giving a pessimistic assessment of my VO2 max because of poor economy when jogging? I have done some Cooper tests, which gave a result of about 49, which is substantially higher than the estimate from my watch of 46.
