FTP Calculation

[CB357]

I’ve been out of cycling for quite a while, but have always kept reasonably fit by riding an indoor trainer with power meter (PowerTap) mixed with a bit of running, and 2 months ago bought my first mountain bike in over 10 years

I’ve also purchased the Masters 40+Cross Country Mountain Bike Build Peak Race Plan 🙂 with the aim to enter my first MTB race (50 km) June 27 to test the waters (haven’t raced anything on 2 wheels in almost 7 years) with another (key) race November 9 (55 km)

Now, as I’ve been out of the cycling world for a fair while, I’m somewhat confused as to the current thinking on FTP calculation (based on the classic 20:00 TT test) as I’ve read so many different ways to calculate it … 95%, 93%, 91% ?

For what its worth, I’m 58, and my latest result this past Friday (on a calibrated CycleOps PowerBeam Pro) was 316W average (and 168 bpm average) so would appreciate some guidance as to the ‘best way’ to calculate my FTP

I should add that I do all my training during the week on the PowerBeam Pro (long story) and drive to the trails etc with my MTB for off road training, skills etc

[Lynda]

The best way to calculate your FTP is using our LW Coaching Power level and heart rate zone calculator We use 93% of 20 min mean max power for our FTP estimate.

FTP is defined as the power you can sustain for 60 minutes – so anything other than a 60 minute test is going to yield an estimation of FTP. This is an acceptable trade-off for mountain bikers.

We have found that 93% of 20 min test power yields on average the most accurate estimate of FTP. We used 95% some years ago and found that it almost always overestimated FTP and led to training level targets that were difficult to sustain. It is quite possible this is an effect specific to mountain bikers since we don’t do many flat out hour long sustained efforts.

Lynda

[CB357]

Thanks for the clarification, and 93% it is 🙂

[Author]

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