and that you can’t take statements like “type 2 use twice the oxygen as more efficient type 1 fibers” out of context. You need to actually run the numbers.
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The 120 units was a restraint that I imposed, that is how the muscle fiber counts were computed.
And yes my point was to prove that the “Type II fibers use 100% more oxygen” and the “9% more power at a fixed energy consumption” can both be correct. Should not just blindly compare numbers from very different studies
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@madman2 absolutely and thanks for the example and I figured that’s what you did. Just wanted to make it explicit. And like you said, it is a massive oversimplification to illustrate the point that both statements can be correct.
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Do you guys also test your decoupling at LT1?
I check my decoupling for base rides, for me I ride between 160-180watts, easy endurance.
Recently I did a test of 50min at (what would be my LT1) 210W indoors.
is it normal that I had a 0,6% decoupling?
Does it mean my LT1 is higher?
Or you are recovered, properly fueled, hydrated and cooled or you haven’t touched your fast twitch fibers as the test was pretty short. I have often negative decoupling during shorter (2h) z2 rides.
I usually do not care about decoupling but rather focus on EF. If EF is trending up in the macroscale, you are on a right trajectory.
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Yeah, it was a rather quick question. Did not really think about it ;-).
Goal is to improve my rides around LT1 power in duration and doing some simple Z2 work (60-65%) for longer durations. I also check my EF. It is now around 1.5 for my Z2 rides. What would be a good number?
Do you track EF for all intensities or only Z2? Or maybe alse tempo, sweetspot? Because higher intensisty, means higher EF, not?
Better than your previous trend. It is related to your power so higher the power, higher EF. If your RPE for a given ride stays the same but EF improves, you are trenindg in the right direction. I would check specific rides only, like your longer z2 ride and only in macroscale, as your HR can be highly variable.
I do not track EF for other type of rides. RPE will be my main indicator of change along with power in efforts sst and above.
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As you use intervals.icu also here is a graph I created which you might find of interest also and addresses some of your queries above in part:
I track it for all my endurance rides - I name these with a #endurance after to be able to filter and I also check it for all rides just for comparison but the metric of key here is the EF for endurance rides. I also find use in having a decupling line and HRRc which provides some context to the type of training I am doing at the time.
In terms of a “good” EF number - its individual to you - you want it to be trending upwards to show progress relative to you.
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Are you actually testing lactate to determine LT1? Quantifying aerobic base in a metric like EF or Aerobic Decoupling can be challenging. I think it helps to understand the history before grabbing metrics out of an analytics platform like Intervals or TrainingPeaks or WKO. Joe Friel has been blogging and writing about this topic for 15 years or more.
When you think about longer durations, I see you posted one for 50 minutes. When you read the early writings of Joe Friel, you’ll see 2-4 hours as the target for cycling. How long are you planning to make the rides?
I did a lactate test end of July. I think my LT1 is higher now, but it could be correct. That is why I wanted to try a session for about an hour at that wattage to see if I would have some cardiac drift. Now, I am more a century rider, I can ride 90min+ at sweetspot. Maybe that is why 50min is too short for this test (was just a quick test without many thinking before I started).
My goal is to extend the time at that intensity to 3h, maybe 4? It is not easy Z2 but more upper Z2/lower Z3. Maybe I should read the Friel stuff again. When I want to start my base phase. I would like to mix long Z2 rides (60-65%) with those LT1 rides and increase the length of those rides…
Maybe its already been discussed but getting a true apples to apples comparison of heart rate over time is tough for me. For it to be meaningful it should be longer in duration. Its amazing how power to heart rate is linked to temperature. In a single ride, I can watch my HR drop at the end of a ride as the sun goes down with same power. On longer rides 3+ hrs in any kind of heat, dehydration will drive heart rate as well. In the summer starting at dawn the HR climbs as it gets hotter. I dont know how you can eliminate all of these external factors unless you are able to be in a controlled environment where your core temp and hydration can be maintained. Anecdotally, my HR recovery gets quicker as I get fitter. Dont know if it really is a function of aerobic fitness though.
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I’m sure you’ve thought of this, doing another lactate test would provide the easiest answer to your question.
Regarding cardiac drift, if I’ve been training or riding for months, then I see low drift (0-3%) on zone2 out to 3+ hours and tempo/SS/zone3 out to 90+ minutes. That is true even when other metrics are improving. For myself, aerobic decoupling is not a good way to test for increasing fitness.
If I had lactate testing performed, then I would expect to also be given power and HR zones. With that information, I would look for increasing power at the same HR. For example lactate testing 4 months ago resulted in zone2 HR at 128-143bpm, and power at 160-202W. Now 4 months later I’m doing 215W at 140bpm, this might be a good sign that aerobic fitness and/or ftp is increasing. Assuming decoupling is still low on 3 hour zone2 rides. But I haven’t done lactate testing, this is what I’ve read and not from my own experience.
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