Sufferlandrians using Xert to track fitness?

I train with The Sufferfest Training Plans and I find that Xert is a good tool to track your fitness history.
Sometimes I have a breakthrough on workouts like The Tool Shed, The Shovel or Violator (sounds obvious as an attacker), in the middle of the Training Plan process. When it happens I use to adjust the 4DP numbers with the new Power Profil report. I am right or wrong ?


I can’t say whether you are right or wrong because I’m not qualified but I never change my 4DP metrics unless I’ve done FF.

The Sufferfest has such an holistic approach to training and testing that having a good day on any given workout doesn’t really mean that that particular metric has truly risen because you haven’t really tested your other metrics during that workout.

My belief is trust the system and follow the plan. If the plan says you’ve improved your metrics (through testing, either FF or HM), then change. Otherwise, let them be.

All IMO, of course.


I’m not currently in a training plan and cannot bring myself to do full frontal anytime soon if ever again as don’t really need to with xert, so I just adjust my 4dp numbers to match my xert power curve which i find to be scarily accurate and actually more detailed than 4dp. I don’t know how regular you should update if in a structured plan, most plans have half monty now in the middle to get an update.
I run both as the suf videos/music is only way I can be motivated to train indoors, I get mind numbingly bored after 1 min of looking at a plain bar chart like a tr or xert workout. If I’m feeling strong I can turn erg off and push over the power recommendation to see if I get any breakthroughs or get my breakthroughs in a strong outdoor group ride. I’m very interested to hear how other people use both.


I use my workouts with BigRingVR and my own playlists for music.


Thanks Dean.
I made a 3 months break with cycling and I couldn’t start a new plan with my 4DP numbers or expose myself to FF
So before starting the Fitness Kick-starter TP, I rode a group ride on Zwift and made a breaktrough. No surprise my fitness has dropped. Then I have adjusted my 4DP with the Xert power curve number to start the plan and avoid overeaching.


I think that if you train with SUF plans and use Xert as a tracker, you should probably stick with the plan, in your case SUF.

However, imho the other way around would be better - use XATA for your training plan and run SUF workouts to avoid having to look at a bar…

In that case, you should probably keep your SUF numbers on par with Xert’s.


Hi @NicoAttacker,
You are not wrong. However, I recommend that you are careful about how often you raise the targets without considering all of your metrics. We all have good days and bad days and it is certainly a nice feeling to get the breakthrough notification. However, if you are consistently getting these notifications I would say it is a good indication that things are moving in the right direction and it is ok to raise your targets and I recommend that you follow this up with a retest. Either with the Half Monty or a Full Frontal. This will give you a better representation of your full profile rather than metrics that are in isolation.


I do exactly the same, in particular when doing a test does not fit in my training schedule. So far I can say that Xert has been great in modeling fitness. While I agree that there could be a risk in pushing optimistic numbers into the SUF model, the advantage of extracting fitness signature from all of your recent riding history, vs, just one test is that you are constantly moving the bar.
If you test say every one month, in the week prior to the next test you will be training with a stale signature. If you instead update your signature every week, the power targets will always be close to the optimal training stimulus.

To @Coach.Jeff.H point, it is true we have good and bad days. It’s not unusual to do tests on a bad day, so it goes both ways.

I update my signature as needed from Xert and make sure to compare with SUF tests when I run them (and there’s usually very good matching)



Just discovered Xert myself and it seems to be a nice addition to SUF in order to track progress or analyze workouts.
I couldn’t find a SUF team there how comes? :wink:



@NicoAttacker I had used Strava premium to track my fitness and performance but find the analysis a bit confusing and messy.

Heard good things about xert so I’m gonna give it a try

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You may want to head to instead…

(That’s not a training platform like Xert or TP, but it offers mind boggling analysis tools)


@Cyclopaat thanks. This looks exactly what I was looking for. Why have I not heard of this before.

Will research and potentially get this. Plus it’s free?!?!?!


Yes, it’s free. If you do find it to be everything you ever wanted, besides your daily dose of flogging, consider a donation or becoming a Patreon.

Currently, the Patreons cover the running costs of the service - David is not (yet) making money, but I sure hope he will soon. There is hardly anyone running something similar - for free - that puts more energy in it.

Head over to the forum and have a look :sunglasses:


I’ve been trying to use Golden Cheetah, but it seems like a steep learning curve and I haven’t been able to spend a lot of time digging into it.

Will give a try!

+1 for
The web app works flawlessly on iPad/Mac and even iPhone/android.
I’d encourage to donate via Patreon if you like it and join the forum.

Wouldn’t waste my time with GoldenCheetah, the tool have become too complex to use and requires a significant time investment to customize.


I use ‘elevate’ it’s a google chrome extension that pulls your strava data and gives you the fatigue, form fitness trend. It’s only available on computers, no app support, no webpage support, it runs on cached data inside your chrome extension.


I use Cycling Analytics which provides a huge amount of useful analysis tools with a nice user interface. It is definitely worth checking out. The Strava fitness tricker does not seem useful to me (it certainly doesn’t track my fitness), and Xert doesn’t seem to provide as much granularity (although it takes a different approach and reports some things that Cycling Analytics doesn’t).

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Elevate and some others like that, are great, but are not an option if you do not run Chrome based browsers, neither of which are the best choice.

Besides, offers a whole lot more…

Cycling Analytics is a lot (more) like, but not free. That said, I’d like to see anyone using to make at least a donation.

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I second the opinion of amazing stuff (and free!!!)


I use Golden Cheetah and really like it, especially now that it can pull data from Strava.

I also use and find myself using that more since it’s so convenient. He also has it programmed to look at breakthrough efforts and it’ll notify you if you get a new best power in the time durations of your choosing. That reminds me that I need to make a donation soon.

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