After more than a decade of being off the bike, I began using Zwift with a newly-purchased smart trainer and almost immediately realized that I was going to quickly get into trouble given the addictiveness of Zwift and my history of overtaining.
Hearing about TrainerRoad and thinking that structured training may be the key to keeping myself out of trouble, I signed up and immediately began listening to their “Ask a Cycling Coach” podcasts.
Based on the podcasts, I selected the Sweet Spot Low Volume I plan and started with the 20 minute FTP test resulting in a FTP of 76 watts which was almost surely underestimated since I started the 20 minute interval way too hard.
After 36 hours of exercise-induced insomnia, I was finally able to get some sleep and then began analyzing the results. Things that jumped out at me were…
- Normalized power for the workout (79 watts) was greater than estimated FTP
- Five minute power was 127 watts = 167% of estimated FTP
- Max heart rate during the five minute effort was 186 bpm while average heart rate during during 20 minute effort was 90% of that (167 bpm)
Normalized power for an hour session being higher than FTP just doesn’t seem to make sense and a review of others’ tests showed FTPs higher than session normalized power.
If a Vo2 max effort is one that a rider is capable of maintaining for three to six minutes then five minute power should indicate Vo2 max power and if Vo2 max power is expected to be 105-120% of FTP then I’d expect FTP to be somewhere between 106 watts (127/1.2) and 121 watts (127/1.05).
Other anecdotal information included…
- A recent 45 minute fun ride averaging 97 watts
- Average from three recent one hour fun rides was 85 watts
- Golden Cheetah CP = 100 watts
Looking at heart rate…
- max heart rate during five minute effort = 186 bpm (but it’s probably higher since I wasn’t testing for max HR)
- 20 minute HR was 167 bpm (90% max)
Since lactate threshold zone 4 is 80-90% then there doesn’t appear to be anything out of whack here.