Information overload.

Hi, I’m wondering if anyone can help. This is as much a cycling physiology question as it is an Xert question, I got quite a big jump in my fitness signature today FTP 230 from 195, HIE 27.5 from 22, PP 972 from 976. I use a few other devices and systems which all gave me quite different FTP estimations so I’m trying to figure out what’s what.

A bit of background - I’m 30, I’m heavy (107kg, 30% body fat 5’11"), I’ve been cycling for quite a few years but have only recently started to try to train properly. Before that I played mostly team sports, did High-intensity intervals, and lifted weights. My setup is PowerTap P1 pedals, Garmin 935 to record, Previously I mostly used TrainerRoad and TrainingPeaks for my workouts and data collection, my trainer is a Tacx Bushido.

I’m currently 6 weeks into the TrainerRoad Sweet Spot base program. On Tuesday I did my second FTP test with them which gave me an FTP of 203 (previously 189), however I learned afterward that it was only reading (and doubling) the left PowerTap pedal due to a quirk of Bluetooth and their app. My L/R powe r was 52/48 so that result could be as much as 4% high (so maybe 195). I didn’t get a breakthrough for this and my MPA never went near my power in either 8 min interval.

Yesterday I did a TR workout called Kaweah which is 90 min long and has 5x10 min efforts just below threshold. I couldn’t complete it and had to bail in the 4th effort, however again my MPA did not go near my power.

Today’s breakthrough ride was a ride with a friend for a couple of hours up quite a few climbs, I put in quite a few big efforts and felt good most of the day. The ride is broken into two parts as we stopped for a beer on the way home. The breakthroughs are in the first one. After the ride my Garmin told me my new FTP was 215, TrainingPeaks told me it was now 209, and on Xert it increased to 230, the day after I failed to complete a TR workout with my FTP set at 203 and me form well into the red.

I generally find low intensity rides to be fairly strenuous, and I prefer higher intensity workouts, those sub-threshold efforts kill me but I do hold quite a high cadence for them (90-100) vs lower cadences (60-70) with much higher power on steep climbs.

Can anyone tell me what my real FTP is? The current range is 195-230. Also why the big discrepancy? Is it due to being fairly untrained in terms of endurance sports? Am I basically using my Type 2 muscle fibers to get the higher power numbers but have sucky type 1 fibers and a crappy aerobic system?

Any input is MUCH appreciated! I’m mostly curious but could also do with a decent guide for where I should set my FTP for my next TrainerRoad session on Tuesday.

Thanks in advance,

(Sorry if the post is a bit long)


Unless your specifically test for your FTP using Garmin or TrainingPeaks, it will almost always underestimate your FTP. Any 20 minute effort likely contains periods where you go below FTP, even rest, and these will not get accounted for properly when you use simple averaging.

Getting comfortable at FTP for someone with a high HIE relative to their FTP like you do will take more training than others. Your Lower Threshold Power is much lower than your Threshold Power indicating that low intensity efforts are going to be very uncomfortable.

Thanks Armando. That helps make sense of things a bit more. I might try a TrainerRoad workout with my FTP set at 230 once I’m properly rested again. I’m eagerly awaiting you iOS app so I can fully switch over to Xert for my workouts! Until then, would I see a big benefit in adding a decent volume of low-intensity work along with the threshold stuff? Or will the threshold work bring the lower threshold up along with it?


I have the same question, but don’t know if I think it’s too simple… How to improve LTP?

Current signature
1034 PP
17.0 HIE
231 TP
188.4 LTP

LTP will go up as your FTP goes up.

Did my first TR workout with my FTP set to 230, 6 x 3 min VO2 max intervals. It was fairly brutal but I managed it so that does seem to be right for me, and I would probably be missing out on some serious improvements if I’d left it at the FTP test level! Thanks Armando!

Hi Armando, the second part of your comment about the relationship between FTP and HIE is really interesting regarding the perceived effort of FTP efforts. Is there somewhere that you get into more detail on that or is is reflected in difficulty ratings at all?

Not directly, unfortunately. However, if you think about what happens when HIE gets depleted before/during an FTP effort, especially as your power fluctuates above and below FTP, difficulty will increase as MPA declines. This is the problem with going out too fast on TTs. They feel a lot harder without being significantly faster and you may eventually be unable to sustain the effort due to rising difficulty.