Yasso 800's

On tap for today at the track
6 x 800 on 4:05 with 200 walk recovery
I managed to get all 6 between 4:00 and 4:05 not sure if it was the humidity or if I just lost some speed, but I don't remember it being so hard. Of course the last time I did this type of workout my numbers were 4:20 instead of 4:05 so that could be part of it. My legs felt great it was more lack of oxygen that was making me feel not so good, so my vote is for the humidity and 80 degree temps that should not be here in freakin October...