Is it possible to adjust FTP bias for workouts?

Firstly, are endurance rides set to a % of LTP?

If so, my LTP is currently set real low in Xert, meaning endurance rides are more like recovery rides and the power is so low that it’s hard to sit on the seat for more than 30 mins. Is there a way I can adjust LTP bias before a workout so that the intervals are set at a higher power output?

Not looking for advice on LTP, I might be wrong that it’s set too low, but I’m pretty sure I have a good handle on my first lactate threshold and the endurance rides are currently way below that.

Thanks :slight_smile:

Short answer is that yes, many endurance workouts are LTP based, but you shouldn’t have to adjust anything. That’s the point of Xert - to tailor workout intensity to you.

It sounds like you have an issue with your signature (many potential reasons, often due to bad power meter data, or lack of true breakthrough efforts), so I’d just write an email to support and they are always happy to take a look for you. Also note that an inaccurate signature affects training load tracking and therefore XATA recommendations, so best to get it right

Looking at your fitness signature is your best bet here: Ask yourself if it is realistic or not.

It’s worth keeping in mind that LTP isn’t an independent part of your fitness signature - it is calculated from the other values and two riders with the same signature will get the same LTP, even although their abilities under threshold power could be quite different, which may be what’s happening in your case.

Anyway, you should ask yourself whether your HIE and TP are realistic: If your HIE and TP are close together your LTP will be very high, and if they are far apart it will push your LTP too low.

Do you find that work around TP is also a little on the easy side? This would mean that your TP may be under-estimated and your HIE over-estimated putting your LTP far too low.

Mike

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Did you mean PP and TP?

No, but I didn’t explain it very well as they are different units of measurement; one being work and the other power. Perhaps I should have used 6 minute power as a proxy for HIE.

Lets take a few examples based around an TP of 300 W:

HIE = 35 kJ >> LTP = 212 W (71% of TP)
HIE = 30 kJ >> LTP = 225 W (75% of TP)
HIE = 25 kJ >> LTP = 237 W (79% of TP)

You can see, as your HIE gets lower your LTP goes up.

Similarly, if we take an HIE of 30 kJ:

TP = 250 W >> LTP = 175 W (70% of TP)
TP = 300 W >> LTP = 225 W (75% of TP)
TP = 350 W >> LTP = 275 W (79% of TP)

Finally, lets look at a series of combinations that all give an LTP equal to 75% of TP:

TP = 350 W >> HIE = 35 kJ
TP = 300 W >> HIE = 30 kJ
TP = 250 W >> HIE = 25 kJ

I hope that helps.

Mike

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It’s just a symptom of having done so much Z2 over the past 6 months recovering from injury that my fitness signature is off.

I only just signed up so I can’t go back in time and apply zero decay.

Was just looking for a stop gap solution while the algorithm catches up as I start to increase the intensity now. Saying that we’ll then be into winter and I’ll be back to zero decay :grin:

The nice thing is that I get breakthroughs most rides without much effort :crazy_face:

Have you tried setting to no decay, then going back to your last good breakthrough activity before your injury and saving / locking (advanced MPA from memory)? That should recalculate progression with no decay from that point on

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