New Optimized Training Stress Score


Today, we are introducing a new and improved training stress score, called OTS (Optimized Training Stress)

As you know, I/we love our Sweet Spot TSS Rides and the AmEx Rides but we wanted to innovate the old way of calculating TSS to address it’s limitations.

The development of OTS includes three improvements to existing training stress metrics:

#1 OTS accounts for the fatigue that accumulates within an exercise session. Your long ride feels harder during the 4th hour than it did during the first hour because your physiology changed during the ride.

#2 OTS accounts for the increase in fatigue and stress that results from not eating enough carbohydrates during the ride.

#3 OTS accounts for periods of coasting and does not provide training “credit” for that time.

These improvements result in a way of accounting for training stress that is more reflective of the actual work and time the athlete puts in.

OTS will help athletes, coaches and sports scientists better quantify training load to help them fine tune the appropriate balance between training and recovery.

Stay tuned here, for when you can begin using OTS to more precisely measure your training rides!


Very interesting concept Frank and I can see where this would benefit the overall effort of a ride.

Curious how much OTS and NP match up overall in a ride.

Thanks @capfan31 ! OTS will not line up with normalized power nor TSS. TSS does not account for rider fatigue during the ride or carbohydrate intake.

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OTS is one side of the equation, will a standard fascat plan be able to be modified by ots on a daily basis?
Thanks, Tom

100% Tom with development.

Not sure if you read but the Goal of OTS is to
*** help athletes, coaches and sports scientists better quantify training load to help them fine tune the appropriate balance between training and recovery.***

that balance may be found in our Optimize visualization which will then help adjust the training plan downstream (if need be)

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Thanks for the explanation, looks extremely intuitive, is it in beta testing yet?

Very cool. Is this for all TP users or just FasCat plans?

if you follow the Big Cat on strava, you can see that it is definitely being tested. :slight_smile:

I just listened to the podcast and it’s a great idea. I’ve used some “other” trading plans that have modifiers for Whoop and Oura users. The problem I run into is this never takes into account days available to train and or future stressors.
For instance, I’m a pilot, and I’ll get home from a 3 or 4 day trip fairly fatigued. My Whoop band / Oura Ring / HRV will say “take it easy and recover” but it doesn’t take into account that I have 3-4 days to train before I go on another trip and spending 2 of those days “recovering” doesn’t move my fitness forward. Likewise, someone with a M-F job may have a lot of time available to train Saturday, but is at his/her lowest freshness for the week and the wearable says “take the day off”
So, if you could add in “Known or Predicted Future Stress” and “Training Availability” to the calculation that would be awesome as very few of us can wait till life gives us the perfect training day.
What a fantastic tool!
I look forward to seeing it in action,
PS Pretty sure Eric Heiden did the Speed Skating/ Bike Racing thing once upon a time. I think the book about the 7-11 team said it was very common at the time.


Yes, that is a great use case!!

To quote: Our goal with OTS is to help athletes, coaches and sports scientists better quantify training load and help them determine with a higher degree of confidence the appropriate balance between training and recovery.

which includes managing the time you have to train to help create that ‘perfect training day’

Also - Eric Heiden: great reminder

Looking forward to using OTS. Just a question… for those of us using a different approach to a wearable and measuring for example RHR and HRV using manual methods will there be a chance to finger digit manually input this data similar to inputting manual TP metrics?

Yes - there will be a way to manually enter your sleep and HRV data.

For example, if you are getting your HRV data from a heart rate monitor you can enter it into the app.

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Perfect. Hoped that would be the case. Well then … bring it on

Hey Frank,
How’s the ots testing progressing, any update on anticipated launch?


Soon @tomcaldwell9014 , very soon. Sing up with your email or mobile to be notified the minute it hits the apple and play stores:


Thanks for the reply, am excited to try it!
Didn’t see it on the list, but karoo2 compatible?

Right now we are compatible with Garmin & Wahoo and plan to be compatible with the Karoo2 as soon as possible.

I love my Karoo2 and they are certainly one of the up-and-coming bike computers out there!

I wish it were as easy as selecting a checkbox but each integration takes our developers time and we have to ask Karoo2 to do work on their end too (which some other brands haven’t wanted to do )

Just wondering when the ots app might be ready, guess I’m the the only impatient one😃

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Oh we’re getting super close! 2-3 weeks.

I see that you are subscribed to be notified when we launch so you’ll hear it from us first!

Thanks for your interest - we are excited to bring this new technology to you


I am also! I have emailed a couple times. Super Excited!

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