Is relative effort calculated in a different way?
Looking at my recent two training with comparable efforts in my opinion, Strava gave one RE 132 (6.5M, AVE HR 160) and the other one 34 (8M, AVE HR 154)? I don't get it unless it's heavy on Max HR, which does have few spots reached Zone 4 in the first training. Does it make so much difference? Thanks.