u/padvad

My base fitness has fluctuated a lot with different seasons, training methods and similar. Last September I had a base fitness of 140. Now I have a base fitness of 104. However my average speed and hr for the same route are nearly identical. What gives? Does base fitness not matter? Or does it represent something else.

First slide from last September, base fitness 140. Second slide from today, base fitness at 104. Same route, similar temps and wind. Both done solo.