I see its been updated since i took that last screenshot - The author got rid of “Model Fit” which no one really understood and just created confusion.
Now he has added “HR Lag” & “Power/HR” so if you hover your mouse over each number and click - a popup will appear giving and explanation
On the left menu select activities - your calender then appears and you select an activity thats longer tan 2 hrs and has HR & PWR data
With the activity open you select “Activity Power” in the menu
then you get the screen that looks like this
Awesome! Thanks. Will try it out when I get home. TP gives the numerical % but always nice to have a graphic representation. 
Many thanks
Thanks for this - interesting data here. Going to take me a while to dig into it and figure out what everything means.
Never really played around with aerobic decoupling before - what is a good target for decoupling %?
Is it simply comparing my HR at power numbers from the first half of the ride to the second half of the ride and calculating drift?
The screenshot above is from a race without a ton of long sustained efforts, so might be challenging to calculate exactly?
If I go back to a indoor trainer workout (in this case Antelope +5) the numbers are a lot easier to interpret
Is it worth looking at aerobic decoupling for races or is it only worth measuring on long steady efforts?
From what I’ve seen, below 5% is a good indicator of aerobic fitness. I believe these are best done on long steady efforts but I may be wrong in my understanding. I did a 2:45 ride on Friday, and had 4.3% decoupling, but most seemed to occur toward the end
Thanks for the links @mcneese.chad helpful reads for sure
Whole thing seems like it just validates whether or not you have a solid base. Validates that mine is strong, which I already knew. I see <1% decoupling on repeated long efforts indoors on the trainer and low single digit %s on races, with a few even showing pretty solid negative %s
I guess my only feature wish list on this would be a way to track the % over time without having to drill into specific rides to gather the number
Thats on the Intervals.icu todo list now
Sorry for the late reply, I was on a business trip, but i seed Chad already answered your question.
i’m no coach, but from what I’ve researched your numbers are excellent.
As to the rest of what Intervals shows there is a lot of information one can use in one place to track performance and David Tinker is updating and adding features all the time so it can only get better.
Yep I suggested that as well - will be great to track numerous things over time in a chart format - But like David says below/above, its all in the pipeline
Hey guys, so I am looking to do a 60-90 minute easy indoor workout tonight, steady pace, is that enough to give me data to calculate this metric for myself? I’ve been riding strong all year so far and with fall coming I am going to be doing more big rides since temps outside are going to be way more tolerable. Just looking to test this today if I can, not sure if something like Bald Knob or Pettit would suffice of I should go for a longer one like Andrews or Townsend. Not sure if this will give me some indication on whether I should keep riding hard or perhaps taper off a bit for a week or two.
The longer the better. I think it’s been mentioned, but intervals.icu calculated only 2+ hour rides; I believe it has to do with a minimum amount of statistical data required in order to produce a valid result.
OK thanks, just not sure if I have enough time to commit to this today. Couldn’t I just do a 70-80 minute steady effort (cropping out warmup and cooldown) and then compare the starting BPM to the BPM at the end? Or do I compare the max to the average?
I used to test aerobic base by doing 2 x 30min intervals with 5min recovery indoors at 75% of my MaxHR and analyze for power decoupling. It was a quite straight forward to see how I was going.
I have just changed that. Intervals.icu now displays de-coupling % and 1st half / 2nd half dots for short rides.
Hi all,
I’m not quite sure how to use the Pw:Hr, should I select the intervals or it’s a metric for the whole training session?
For example, today a did Tallac, which is a “3x15-minute efforts spent in the Sweet Spot”. The Pw:Hr for the whole session is 11.66% (quite bad…)
However, if I select the last sweet spot interval the picture changes, and it’s 2.08%:
I’ve read the few articles about this topic, but I can’t seem to be able to understand it completely.
Thanks,
PS: of course, disregard the Km, speed of the session, I don’t know what happened with the trainer.
Interval training sessions are not really the right type of session for calculating Pw:HR.
I stick to use endurance sessions such as Town Hill, Appalachian, Longfellow, etc
Could someone explain to me please exactly what is “aerobic base”? I see that mentioned all the time on various forums, but am never quite sure what it means.
Also, what is the scientific basis for “decoupling” and how does it tell you about your “aerobic base”?
tl;dr for aerobic base:
- Increased capillarization
- Increased mitochondrial proliferation
- Increased aerobic enzymes
- Increased cardiac output
- Increased fat metabolism
All of these adaptations coalesce to achieve a shared outcome, which is more oxygen extraction at the muscle.
tl;dr for decoupling:
[T]he limited research available appears to indicate that when aerobic endurance improves there is reduced heart rate drift relative to constant outputs (power and speed)…This parallel relationship between input (heart rate) and output (power or speed) is referred to as “coupling.” When they are no longer parallel in a workout as one variable remains steady while the other drifts the relationship is said to have “decoupled.” Excessive decoupling would indicate a lack of aerobic endurance fitness.
