New user, will Xert work for me if I use it like this?

Hi there! I signed up last week for a trial account and have been poking around a bit. I’m impressed by the possibilities and I’m especially intrigued by the adaptive training advisor.

As a time chrunched mountainbiker most of the year I don’t care about following training plans, I just like to get out on the bike and do whatever I like. Most of the time these rides end up in pretty exhausting high intensity rides (focus time GC, heart rate derived).

In autumn/winter I race cyclocross. I tried some training plans on the indoor trainer in preparation for the cross races but the rigidity of the plans just doesn’t work for me during the build up before the first races. I just don’t enjoy it and miss the fun of mountainbiking.

The adaptive training advisor seems like an ideal tool to stay on the MTB (will need to get a PM) and do some higher intensity rides during the build phase in the weekends, and do a few indoor sessions after work during weekdays to prepare for cross (focus time puncheur/breakaway).

Will the adaptive advisor adapt my schedule to a way that I will still reach my goals? Or will I mess up the schedule with the MTB rides so much that there is not much to adapt anymore? Any insights? Thanks!

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I think what you describe is pretty typical for many mountain bikers. It is not clear to me if you are also racing MTB during the spring season, but in general I would say that the training advisor is adaptive and works well as long as you feed it the right info.
Sounds like your training is not really strictly “structured” but you ride quite a bit and then throw in specific workouts. The nice thing about CX season is it’s not usually one event, it’s racing almost every weekend for 2-3mo. The training advisor on the other hand works on the idea of having one key event, with the typical base/build/race structure.

The way I’d use it is to set the target event from one of the last CX races of the season. This way most of your season will overlap with the build/race phase, where focus is on higher intensity work and less on volume.

If you track the rest of your activities it will keep your signature fresh (having a PM on the MTB would be ideal, but they also have HR derived metrics) and the advisor can recommend the proper the best workouts on a daily base.

With that said, training plans for CX are pretty straight forward, and lot’s of it relies on 1-2 HIIT during the week, lot’s of skills practice and a bit of running (oversimplifying here, but you can find cheap canned plans everywhere).
Tracking activity with Xert will still help you avoid going overboard or under train but more importantly track your progress with your top end power (anaerobic and NM) which will result from HIIT and racing once the season start.

@zenturtle Thanks! Sounds like it’s worth a try. Any idea how accurate the HR derived metrics are for mtb?

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There is a pretty good summary here:

In my opinion not as good as power meter (obviously) but it’s better than not tracking those sessions at all. At the end of the day it’s all bout tracking your overall workload.

I’ve experience of both on and off-road and with/without a power meter.
In my experience, riding similar rides with and without a PM and also comparing perceived effort during a given ride and the following day’s fatigue, Xert’s algorithm consistently under credits you for the effort of HR derived rides.

For a few months, I had a power meter on my road bike, but not on my CX bike and I guessed that the calculation was more geared to road based activities and wasn’t factoring the extra physicality of riding off road, hence the deficit.
I invested in a second power meter for the CX bike and the XSS shot up.

Now, I’ve resurrected an old road bike for the winter- no PM- and, again, on like for like rides, both on the road now, it is underselling things.

Yes, I can artificially play around with the upper and lower heart rate limits I have set in Xert in order to try to boost the XSS given, but, that’s a fudge that puts the onus on the customer. If Xert is all about accurate data then it seems silly for me to pretend my resting heart rate is much higher and maximum much lower just to try to improve the service’s accuracy.

I really think the HR derived aspect of Xert- a brilliant training system, but one with a significant barrier to entry because it requires a power meter- needs seriously looking at again.

In some ways it can depend on how you ride and the quality of the data. If your data has errors, well… it’ll be hard to make up for that. If your rides with power, heart rate and cadence are very different in terms of things like cadence, standing vs. sitting, using different gears a lot, terrain, then the algorithm may not pick up on higher power efforts since they won’t show in the HR or cadence data like they normally do in road data.

For the athletes data we’ve worked with, it can be very precise when the rides are similar. So if your road bike power meter gets sent it for repair, and you have a cadence sensor and HRM, the results should be quite good.

The results aren’t terribly good though I’m afraid. And I’ve seen other customers say the same on the forum.
It’s something that needs work. I’m slightly baffled that, in a product that is ALL about the data, I’ve seen Xert representatives suggest putting in incorrect heart rate data to artificially inflate this aspect of the product. Doesn’t that feel off to anyone else? The onus shouldn’t be on the customers to fiddle with a workaround, the onus should be on the developers to further improve the HR derived algorithm.

I see HRDM as an estimate of power/strain/focus to fill in any gaps for activities without a meter. It’s not meant as a power meter replacement. For example, estimate XSS for a daily commute without power or to include time spent on a rental bike while traveling.
If I planned to do this often I’d get a quick mount cadence sensor like the Wahoo RPM.
Under-estimating XSS is better then overstating it IMO. The goal isn’t a one to one match. It’s so XATA doesn’t think you had a rest day and can better gauge TL.

I don’t think the market for HRDM-only subscribers is significant.
If someone plans to train with power using a platform such as Xert they need as much power data as possible. :slight_smile:

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The heart rate derived metrics need a cadence sensor to work- it’s using both HR and cadence data stacked against that which it’s measured whilst you’ve used a power meter, at a guess.

Having this aspect- one which widens the customer market for Xert, by what amount is for them to know- perform more accurately can only be a beneficial thing for customers.

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Agreed but I wouldn’t say Xert suffers a significant barrier to entry because it requires a power meter.
As you noted HRDM works best with cadence data plus you need power/HR/cadence data on file for the XSS estimate to work as designed. So the base requirement is a power meter on your main bike.
Next factor will be whether that data includes road, off-road, and CX rides each of which has different set of values for comparison, However, Xert doesn’t segregate the data that way so I don’t think there is much more they can do with HRDM other than approximate values and preferably underestimate the strain.
Ideally anyone who wants to train with power has power meters on all their bikes. Hopefully prices continue to decline where that isn’t the deciding issue.

Hi, topic starter reporting back with some observations on mountainbike data while using Xert now for a couple of months.

I went all in after subscribing to Xert and bought a power meter to better track activities on the XC mountainbike (my main bike) to feed the adaptive training advisor with the most accurate data available. Now I can compare the data for similar MTB rides, without and with PM.

  • My local MTB tracks are flattish with lots of corners, bumps, jumps and really short punchy climbs/decents. I ride a lot around and above threshold HR with regular recovery opportunities. When I ride my local loops, I’m pretty much toasted in the end. Tracks are no fun riding at endurance pace, you need to push it to make them fun (because they are so flat :slight_smile:)
  • HR derived metrics for rides on these tracks are showing high XSS values, probably based on the prolonged time spent in HR near threshold
  • With power meter the XSS of a ride is around half of the XSS based on HR derived metrics, on the same tracks. A 3 hour mtb ride that tires me a lot gets only a little more XSS than an easy endurance gravel ride, which doesn’t seem right.

My conclusion: when using a powermeter on these kind of MTB tracks, Xert only sees the power when I’m actually pedalling. Xert doesn’t take into account the power used when I’m not pedalling like decending, absorbing shocks, jumping, pumping, etc., which gets my HR going and makes it a hard workout. The live MPA on my Garmin barely dips while in fact I’m pretty much toasted. Therefore I think it doesn’t estimate the XSS well enough for these kind of trails. Probably this is the same issue runners encounter to accurately estimate XSS for running.

I think I’ll put the power meter on the CX/roadbike and stay with HR for my MTB rides. Probably the power meter will work better for CX racing as less energy is spent on ‘non-pedalling power’. With hindsight I wouldn’t have bought the power meter but now I have it, it’s kinda interesting to see how much energy actually is spent on other things than pedalling. Also gives some insights on whether or not the MTB rides are useful for CX training.


That’s very interesting. It will be interesting to hear the reasons.

Although MTB and Road cycling are both based on riding bikes, the efforts are quite different as you point out. In some ways, it is similar to comparing running to road cycling. The exercise modality is different, using different muscles and motions and fatiguing differently.

You can mix disciplines in one account but it will require a bit more attention to properly allocate the appropriate XSS towards the discipline you are most interested in tracking and improving. Each account only has 1 fitness signature, hence is really meant to help you quantify and manage 1 discipline at a time. So if you’re wanting to improve MTB, for example, you’d want to track XSS for those efforts and identify other XSS from other disciplines that will positively (or negatively from fatigue) affect your MTB fitness.

We are working on features to make this easier to manage. “Multi-profile Xert” is in development. Unfortunately we can’t commit to a timeframe for availability given all the other things being worked on at the same time. However do know that this is on the higher end of priorities for us.

In the interim, it looks like you have a good handle on things and the right ideas on what to do. Keep up the good work and good luck!

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Thanks, looking forward to the multi-profiles. In the meantime I think only HR is good enough to gauge training load and plan workouts for CX racing, which is was my primary goal. Now if only there were some races…

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