The phenomenon of FTP determined by 4DP on a trainer generally being lower than that determined from 20 minute intervals done outside has been well-covered in Sufferfest articles. But I thought that it would be interesting to share my own experience with this and see what others have experienced.
I started using a power meter last year, using a free subscription to Training Peak and the open source Golden Cheetah software to analyze my rides. I found a reasonable stretch of road to do a conventional 20 minute FTP test and returned to it several times during the season. The very first test put FTP at 190, which improved to 210 around mid-season and settled at 200 as the cold weather set in. Golden Cheetah’s “extended CP” model gave similar estimates.
I then started using Sufferfest workouts in ERG mode on my newly-purchased trainer. My first FF set my rider type as Pursuiter with FTP as 181. After completing the 12-week All-Purpose Road plan and the ToS, a second FF showed no improvement in FTP, but did improve NM and MAP, still a Pursuiter. Following a further 6-week Power Builder Program, a final FF showed FTP improved to 187 and rider profile changed to Sprinter.
I’ve been riding almost exclusively outside in the three weeks since the last FF and today tried the 20 minute FTP test for the first time this season. Subjectively, the experience was challenging, but not quite as draining as I remember from the final attempt last year. Nonetheless, Training Peaks estimated FTP at a personal best, 222. Golden Cheetah gives a similar estimate.
The main take away message is that the Sufferfest programs work to improve performance on the bike outside, both subjectively and as measured by other algorithms.
Have others had similar experiences?