Hehe, ok. That is another ballpark ;-).
Should be great when you have endurance like that ;-).
After months of training, now I can do 281W for 90 mins (Tempo) - I think I can do longer but have to gradually increasing. (The load is high for my fitness now)
Fatmax from last year test was 158 bpm. Today’s ride mainset is avg 161 bpm.
Even HR is higher but I’m feeling better. 2-3 years ago 280W was my FTP. Now Garmin detected current FTP 324W but maybe already higher because I did not do 20 mins intervals much.
^^
So I am just curious for those that do an endurance ride and end on a ~15-20 second sprint…have you noticed extra fatigue carrying to your next session? Or is that just like nothing?
I do remember ISM saying he ends a lot of his endurance rides with a sprint.
oh man. i’m somewhat new to cycling (~2 years) and ISM got into my head early. so it’s gonna be hard for me to shift my mindset on this. also Seiler telling a story of watching a high level runner walk up a hill to avoid going too hard.
I guess I’ll just give it a try and see
there’s for sure a few hills on my rides that are painfully boring in Zone 2
What’s missing there is that is probably an elite level athlete, training 20+ hours a week and being really good at auto-regulating.
Seiler has often been illustrating that top athletes do hard / easy and leave enough in the tank for the next hard session. Many amateurs tend to ride a lot of tempo and chase every city limit sprint on a ride with their friends and are often always tired.
Not sure about the study title, they never define what the main goal of endurance ride is.
The idea from san Millan is that long endurance promotes mitochondria fusion, and vo2Max promotes fission. Short intense efforts (15-20s max) do not put strain on mitochondria as the spikes are short (oxygen need and ROS production).
The paper does not study this at all, especially with the pre and post 3 min max efforts that are the exact opposite of what San Millan recommends during endurance rides.
I suspect this is due to
Myoglobin in the muscle cell functioning as an oxygen-store at the beginning of each short interval, reducing anaerobic glycolysis and lactate build-up.
Discovered back in 1960 by Åstrand
Combined with the ATP-PC system.
this study says 3 minutes all out, right? they are talking about more than a spike here I believe.
ok got it
thank you!
From this YouTube
Where is mitochondrial development maximized?
The best pace for mitochondrial adaptation lies in the range 11.5–12.5 km/h, but not all paces stimulate it equally.
Physiology principle: Mitochondria grow when…
Mitochondria develop best when these three factors occur simultaneously:
-
High enough metabolic stress (↑AMP, ↑Ca²⁺, mild ↑ROS)
-
Still fully aerobic (no excessive lactate accumulation)
-
Maintainable for 30–120 minutes
So we need a pace that is “hard enough to stimulate mitochondrial signaling, but not so hard that it becomes threshold or anaerobic.”
This is what we call Upper Zone 2 / LT1 + ~10%.
Pace-by-pace analysis from the graph
10.5–11.5 km/h
-
Lactate 1.2–1.8 mmol → very low
-
Highest fat oxidation
-
Low metabolic stress
Great for building mitochondrial volume
✘ But not the strongest “stimulus” for rapid mitochondrial growth
12.5 km/h
-
Lactate ~3 mmol → mixed fuel use
-
Still below LT2
-
This is Upper Zone 2 / Low Tempo
Produces the strongest mitochondrial adaptation signal
Optimal range for ↑AMP, ↑Ca²⁺ while staying aerobic
Can be sustained for 30–40 minutes
Research shows this intensity maximizes PGC-1α (the master regulator of mitochondrial biogenesis).
13.5 km/h
Lactate ~5 mmol → approaching LT2 / threshold
✘ Too much anaerobic contribution
✘ More glucose-dominant
✘ Not optimal for mitochondrial development
Useful for threshold training, but not for mitochondrial growth
Coach-level conclusion
➤
Best for mitochondrial development:
12.5 km/h
Provides the ideal aerobic metabolic stress to maximize PGC-1α and mitochondrial growth.
➤
Second best.
11.5 km/h
Excellent for fat oxidation and aerobic volume, but weaker stimulus than 12.5.
➤
Not optimal:
✘ 13.5 km/h
Too close to threshold; produces more anaerobic stress than needed.
What in the ai slop is this?
It is from ChatGPT, I think it can answer for Dr.Inigo Z2 Confusing. (If you follow him you will understand)
Huh? Running paces for a cycling forum? Even more confusing than ISM.
Dr. Inigo Zone2 is above LT1. So it is “ low Tempo “ and not the same as most scientists or coach understand. (That is why UAE Riders have to consume a lot of carbs while training Z2)
You have to wonder why he had to call it zone 2 when zone 2 already had a definition.
I’ve often wondered that.If it had been anyone else I’d have assumed it was for more clicks
AI Slop
Huh? No it’s not. Or at least that’s not how ISM has ever defined it.