I started with athletica using my critical pace and power numbers from Stryd. I updated them every now and then when Stryd gave me an update. As I found some workouts in my current training blog too demanding, I double checked if my zones are right.
My current critical power from Stryd is 319 watts. But my athletica Running Power Profile has a CP of 296 watts. As both profiles are fed with the same data, the difference between the CPs probably lies in the different definitions what CP is.
Nevertheless: it’s probably the best way to work with the CP from my athletica profile and enter this number (296 watts) under Settings-> Thresholds → Run. Is this the right way to do it? I’d do the same with my critical pace then.
Why don’t I get notifications, if my values are off?
You can manually change your CP power under Overview - Athlete Zones - Critical Power and / or Critical Pace if you think they are not correct. As you mentioned, different platforms may estimate CP using different methods, so it is difficult to get them to match all the time.
Sounds like Athletica CP may be better fit if Stryd Power is feeling too demanding.
What do you mean you don’t get notifications if your values are off? Sorry I am not following you there @harlerunner.
Best, MJ
I sometimes receive notifications when a change has been detected in my training zones. So far, this has only ever affected zone 7 and involved minor adjustments. However, if my recorded CP deviates so significantly from the calculated CP, I would have expected athletica to notify me about this as well. But that has never happened.
I have posted about this before, but it seems like it may help @Harlerunner so I will mention it again. Early on, Athletica used the term “threshold”, but this was changed to “critical power/pace” maybe two years ago. The problem with this change is it goes against conventional definitions of these terms.
If you do a web search or ask AI to explain the difference between Critical Power and Threshold Power, you will find the former to be associated with 30-40 minute power and the latter with one-hour power. To complicate matters, CP is typically (mathematically) derived from “best efforts” ranging from 3-20 minutes. This means the CP curve sits atop the mean maximal power plot (asymptotic to the highest peaks/best efforts).
If you look at your power profiles in Athletica, you see something that approximates WKO’s PD curve (with points above and below the modeled line). Finally, Athletica’s CP (at least for me) falls below the modeled one-hour power. Notice in the help charts, threshold his placed ABOVE Athletica’s CP.
So, why does Stryd’s CP feel much harder? Because Stryd is using the conventional definition of CP (30-40 minute pace/power), while Athletica is using what (in my opinion) should be referred to as MLSS (maximal lactate steady state).
None of this is to say that this negatively affects training. Athletica’s use of a separate model (APR) for high intensity ensures high intensity sessions are prescribed correctly, and basing aerobic work on a lower value probably is beneficial in terms of keeping easy sessions easy. But the naming convention for anyone who’s spent time reading about this stuff is confusing.
