Iñigo San Millán Interview: Mitochondria, Zone 2, and metabolic health

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January 4, 2020 at 7:23 pm #35448

depeyster
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This is a very long podcast (interview starts around 7:30) of a researcher who recently coauthored this paper with George Brooks, the man behind the lactate shuttle that plays such a key role in both of Steve and Scott’s books.

He gets pretty deep into some details, so, of course, there are some small nuances where he differs with Steve and Scott. If I understood him correctly, he makes AeT the Fatmax point, as opposed to an RER of 0.85. But in this very wide-range discussion, almost everything he says provides a strong confirmation of the validity of what Steve and Scott are advocating.
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Posted In: General Training Discussion

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Anonymous on January 5, 2020 at 3:51 pm #35495

Thanks! I’ll check it out.

Keymaster

Steve House on January 7, 2020 at 12:54 pm #35655

This is a GREAT podcast and I highly recommend it for anyone who wants a better explanation of the physiology than Scott and I could ever muster. Thanks for posting.

Participant

niall f on January 8, 2020 at 9:11 am #35720

What would people think about a sticky where UA-relevant podcasts could be posted as they appear online? There’s lots of interesting podcast shows out there, and it can be hard to keep up with all of them on one’s own.

Participant

Adam Fern on January 8, 2020 at 11:02 am #35732

Peter Attia has a wealth of content relevant to UA. Nutrition, metabolism, exercise science, among other topics. His feed is a great place to start.

Participant

Aaron on January 8, 2020 at 9:26 pm #35813

I like the idea of a sticky thread for cumulative and curated podcasts. That Peter Attia episode is really good. Took me two zone 2 workouts to finish!

Participant

xcskier on January 14, 2020 at 8:08 am #36247

One of the things that San Millan emphasized is the importance of Zone 2 training,
not surprising. What was surprising was his statement about the volume of Z2 training
(for professional cyclists). He seems to suggest that they do much more Z2 training than
what I’ve seen discussed in the context of “uphill athlete”. He mentions this in another
article:

Zone 2 Training for Endurance Athletes: Build Your Aerobic Capacity

The explanation I’ve seen was that once you start getting faster (=better endurance)
that you start replacing Z2 sessions with more Z3 sessions. But after listening to
San Millan it seems that man pro-cyclists have a large volume of Z2 training.

There was also a discussion about training (and especially racing) on low carb
diet. San Millan believes that even training in a fasted state is detrimental:

Thank you for listening! My personal opinion is that training even at Z2 under CHO restriction/ketosis + fasting may be damaging and not very effective at improving mitocondrial function much. But that’s only my modest opinion

— Iñigo San Millán (@doctorinigo) January 2, 2020

Inactive

Anonymous on January 14, 2020 at 11:35 am #36251

I’ll check out the links, but first a clarification on what we recommend for changes in the intensity spectrum.

When someone is new to training, Z2 is not very fatiguing. For folks with severe ADS, it may not even feel like exercise.

The first response is for the AeT and AnT HRs to converge (as AeT HR rises closer to AnT HR). At that point, Z2 is probably still pretty manageable.

The second response, which can go on for years, is that the AeT and AnT speeds rise and converge. As that happens, AeT becomes more fatiguing, not because it’s metabolically stressful, but because it’s neuro-muscularly stressful.

As AnT and AeT speeds increase closer to an athlete’s genetic maximum–and/or the tolerance for them increases so the possible duration at those paces also increases–the fatigue from Z2 training is more similar to Z3. At that point, Z2 and Z3 don’t feel much different.

As that happens, we recommend replacing Z2 hours with Z1 hours, not with Z3.

I’m still working through that podcast, so I circle back when I’m done. (If Peter Attia could resist blah-blah-blah-ing about his personal performance anecdotes it would have been a lot shorter.)

Inactive

Anonymous on January 14, 2020 at 11:58 am #36252

@xcskier: To be honest, I’m not sure. 60-75% of total volume in Z2 for a pro sounds like a hell of a lot.

In the article, he defines Z2 as 55-75% of VO2max. Is that a typo? Coggan’s “Zone 2” is 55-75% of FTP (which equates to ~63% of VO2 pace in Coggan’s system: 75 / 120 = 62.5%)

Compared to Canova’s marathoners, the latter number (~63%) would be similar for most of the volume while the former would not. For example, in the three and a half months leading up to Moses Mosop’s 2003 marathon debut (where he ran 2:03), his training breakdown was:

LABEL % OF AeT* TIME SPENT PERCENTAGE “ZONES”
Easy 49-68% 100h 57% Super Z0?
Moderate 68-78% 36h 21% Z0?
Sub-AeT 79-100% 33h 19% Z1 & Z2
Super-AeT 100+% 6h 3% Above Z2

* Where “100%” equals AeT, the top of Z2.

Inactive

Anonymous on January 14, 2020 at 12:01 pm #36253

With respect to fasting, I wonder if Millan would distinguish who might benefit from fasted training and who wouldn’t. We recommend it for athlete training under ten hours per week, maybe between 10 and 12, but not for athletes with a volume of 12 hours or more.

Again, Canova uses depletion as well. I haven’t read if he uses complete fasting, but in his “special blocks” (two hard specific workouts separated by several hours), he’ll have his athletes reduce carb intake between the sessions.

Participant

xcskier on January 14, 2020 at 1:44 pm #36269

Maximum fat burning rate can be computed from a metabolic test.
This max fat burning zone will obviously vary from person to person.

Here’s two posts by Jeukendrup who authored several papers on this some 15 years ago:
https://www.mysportscience.com/single-post/2015/03/18/What-is-Fatmax
https://www.mysportscience.com/single-post/2015/08/04/Finding-your-fat-burning-zone
(see paper references in the posts)

Jeukendrup says they found FatMax on average to be around 65% of HRmax (but it can be as
low as 50% or as high as 80%) which is in line with what has been discussed here
and recommended by Uphill Athlete coaches. I guess it all comes down to zone definitions and individual physiology (based on metabolic tests).

And the paper by San Millan and Brooks mentioned in the original post above is this:
https://www.researchgate.net/publication/317660005_Assessment_of_Metabolic_Flexibility_by_Means_of_Measuring_Blood_Lactate_Fat_and_Carbohydrate_Oxidation_Responses_to_Exercise_in_Professional_Endurance_Athletes_and_Less-Fit_Individuals

Participant

aw11gwd on January 17, 2020 at 4:38 pm #36465

@14487946 and @Aaron I had a similar thought a while back in terms of keeping a library of really high quality podcasts to go with workouts. I find them very motivating and I often feel as though I am killing two birds with one stone – getting a run done and learning something or being inspired to set goals etc.

The other observation I had was that you can waste a ton of time trying to find good content. It used to really frustrate me if I accidentally fell down an Internet rabbit hole looking for a good podcast – or a documentary if I was stuck inside on a treadmill.

So I built a website to review content for workouts and to make it quick and easy to to narrow down the options and save your picks for later.

It started out as “Slipstream” but I couldn’t get the full domain name and the url caused confusion.

Now it is at zone2review.com/ inspired in part by what I have learned reading the Uphill Athlete book and listening to Dr San Millan and others.

Also I figure it’s mostly Z2 (and Z1) workouts where it’s ok to be a bit distracted. If I am doing intervals I usually want to focus 100%. Sometimes on a long run it’s good to practice being present and getting into that meditative state but generally on Z2 workouts I let myself be entertained and educated by podcasts, audiobooks, race coverage, POV footage and documentaries, whatever gets me psyched to get going.

I would appreciate any feedback. The mission is simply to make it easier for the audience to connect with the content.