posted Jan-01-2006 12:57 PM         

quote:

---

Originally posted by flynnmcmahon:
QUESTION:
I am trying to do low HR and hopefully lose weight.
I know leitnerj, you have said to do this you strongly
suggest no carbs before or during workouts. My issue
seems to be that without that, I have horrible runs.
I am weak and listless not consuming carbs before
and if I do a longer run (say 45mins or more) and do
not have a gatorade or something, I give out pretty quick.
Am I being wimpy here or could there be something
with my body that requires this kind of intake to run?
THANKS

---

***Barge***

I used to train with my HR in the 155 range.
I am now only doing the 137-147 range. (although now I am trying MAF and going for under 142.
I just did 1 hr 20 minutes with no need for anything. Before I required Gu or gatorade to help me plug along...and I was in better running shape before, or atleast I was more consistant.
 

posted Jan-01-2006 01:54 PM         

Hi Jesse. This does not tally with what I am now reading which has 1/3 of energy from fats at what might be 10k pace (85% VO2Max). It would seem to make sense that fat contibutes even at these high work rates - otherwise how would low HR training improve speed at LT or above?

What do you think?
http://www.gssiweb.com/reflib/refs/32/d000000020000006d.cfm?pid=96&CFID=2869164&CFTOKEN=29144245

The article has some interesting charts

-brian
 

posted Jan-01-2006 03:01 PM         

quote:

---

Originally posted by christa0120:
***Barge***

I used to train with my HR in the 155 range.
I am now only doing the 137-147 range. (although now I am trying MAF and going for under 142.
I just did 1 hr 20 minutes with no need for anything. Before I required Gu or gatorade to help me plug along...and I was in better running shape before, or atleast I was more consistant.

---

Christa, do you eat anything before your runs?

 

posted Jan-01-2006 03:24 PM            

quote:

---

Originally posted by flynnmcmahon:
QUESTION:
I am trying to do low HR and hopefully lose weight.
I know leitnerj, you have said to do this you strongly
suggest no carbs before or during workouts. My issue
seems to be that without that, I have horrible runs.
I am weak and listless not consuming carbs before
and if I do a longer run (say 45mins or more) and do
not have a gatorade or something, I give out pretty quick.
Am I being wimpy here or could there be something
with my body that requires this kind of intake to run?
THANKS

---

The only thing with your body that requires carbs is the
fact that you are used to running on carbs as the primary
fuel source. And, if you need them for 45 minute runs,
it may be something as simple as a "sugar rush" that's
keeping you going. Obviously, it's entirely up to you,
but if you really want to transition to a fat burning approach,
you'll have to wean yourself off of the carbs. I would suspect
that for the same reason, you're also having a particularly
tough time keeping your heart rate down (if not, then weaning
off of the carbs may take a few weeks, but shouldn't be that
difficult). Incidentally, you're not even close to running out
of glycogen for anything less than 2+ hour run, so I would
suspect it's more of a sugar rush thing to you, much like
a nicotine or alcohol addiction (but much of less of a big deal!)
Perhaps if you just fool yourself, that will help. Try using
something that has a sweet taste but that's low in carbs and
calories, such as Ultima, Powerade Option T (their low calorie
version), or even crystal lite (many flavors). These will give
you the sweet taste, and for ultima and powerade, the electrolytes,
but without the carbs. The other option would be just to slowly
reduce the amount or water it down or something. Incidentally,
I love chocolate, I have no interest in giving it up, and further
it packs a lot of calories, which I need to keep from shriveling
up, but I save until I've finished all of my activities for the day.
For you, I would see nothing but significant benefit from eliminating
the dependence.

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posted Jan-01-2006 03:53 PM            

quote:

---

Originally posted by briandirect:
[b]
Jesse wrote...
A less direct method would be to determine HR at anaerobic
threshold (the point at which 100% carb burn starts to occur), and
choose zones as a % of that, MAF being about 80% of that.

Hi Jesse. This does not tally with what I am now reading which has 1/3 of energy from fats at what might be 10k pace (85% VO2Max). It would seem to make sense that fat contibutes even at these high work rates - otherwise how would low HR training improve speed at LT or above?

What do you think?
http://www.gssiweb.com/reflib/refs/32/d000000020000006d.cfm?pid=96&CFID=2869164&CFTOKEN=29144245

The article has some interesting charts

-brian[/B]

---

Ouch, it would take me a week to absorb everything in that
article, and three more weeks to really understand it! (I'm an
associate editor for an aerospace engineering journal and it usual
takes me about 4 days of highly-focused reading just to fully
understand the papers in my area of expertise - no doubt I'm slow!)
Nonetheless, no fat is used for fuel above LT (if you assume that
LT occurs at anaerobic threshold, which by definition is the point
where you hit 100% use of carbs for fuel). Low HR training really
will not improve your speed above LT. It will improve VO2max
and it will push up the LT (both of which are key for endurance
exercise), but above that is purely your anaerobic system. Low
HR training will also prepare your body for the rigors of working
your anaerobic system. Now, back to the article you posted.
The graphs are at least straightforward, but the quantities are
still complex (energy expended and oxidation of fat). Figure 1
is kind of a flow diagram
so I don't get much out of that for this discussion. In Figure 2,
I'm not sure I buy the 25% vo2max and 65% vo2max figures
because they both show a large percentage of glycogen use
for fuel - it may have something to do with how glycogen is
used for fat metabolism, but I'm really not sure. At
85% vo2max, which corresponds to a heart rate of 160 for me,
I'm at about 65% carb/35% fat, which doesn't seem to be far
off what the graph shows. Figure 3, showing a different quantity
(oxidation of fat), seems to show similar results at 85% vo2max,
but I can't say I fully understand what it means. In short, I'm
sure what to ascertain from that article, but suffice to say that
I don't think low HR training will do anything to improve the
anaerobic system (above LT), but it will transfer some of the
speed of the anaerobic system to the aerobic system. So if
your goal in life is optimal performance at the 100m sprint,
this may do nothing to help you, other than perhaps help give
you some strengthening in the off-season. Incidentally, an old
reference that gets into some of the carb vs fat stuff is
G. Lusk, "Science of Nutrition," 4th ed., Philadelphia,
W.B. Saunders Co., 1928, p. 65. Good luck finding it!

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posted Jan-01-2006 04:59 PM         

quote:

---

Originally posted by flynnmcmahon:

Christa, do you eat anything before your runs?

---

posted Jan-01-2006 05:16 PM         

quote:

---

Originally posted by christa0120:
[QUOTE]Originally posted by flynnmcmahon:
[b]
Christa, do you eat anything before your runs?

---

Christa, thanks for responding and than re-responding. (I hate when that happens!)So I get that your eating post runs and than thru out the day, we're talking less of a need for carbs here, so now I'm wondering, as I asked Leinterj above, are we talking low carb when your eating? Please say no!

 

posted Jan-01-2006 06:30 PM         

quote:

---

Originally posted by flynnmcmahon:

Christa, thanks for responding and than re-responding. (I hate when that happens!)So I get that your eating post runs and than thru out the day, we're talking less of a need for carbs here, so now I'm wondering, as I asked Leinterj above, are we talking low carb when your eating? Please say no!

---

OK...here we go.
When I am following a healthy eating plan....(not that I follow one all the time)
I TRY to eat a ratio of about 40% protein, 30% carbs and 30% fat. I eat lean meats, all the veggies I can stand, fruits and "healthy fats" like avocado and UDO's oil in my protein shakes and nuts or nut butters (raw, ofcourse)
Where this is "lower carb" then most "runners diets" I am still eating lots of carbs. I am just trying to eliminate refined/processed foods. Take away bread and tortillas and that drops me 20% right there ...lol
Basically I try to eat very cleanly WHEN I am on my good girl kick..
Last night I had spaghetti with meat sauce, green beans and garlic bread...so I am no carb nazi!
Did I mention the peanut butter cups for dessert?
 

posted Jan-01-2006 08:33 PM         

quote:

---

Originally posted by flynnmcmahon:
Thanks Christa, always interesting to hear what people are doing. Do you have any weightloss or running goals?

---

I want to do another marathon. Perhaps do the San Diego one again. Definately do better then the last time. I'd like to get under 5 hrs this time. In June my goal was 4:45. I didn't train as consistantly as I should have and my time showed.
Like I said in earlier posts I am really just hoping to find my running mojo again. And as far as wight goals go, oh yes, Id love to lose atleast 30 pounds. I have 3 demons working against me there tho. My DH/family, time and myself.
My dh will "unintentionally sabotage" my efforts by bring home things I find irresistable...like cake, cookies popcorn. I love to munch! Time because I work 12 hr days and it is hard to plan what I might need on any given day. It seems that I can eat only 2 meals when I eat the crap out of the cafeteria but I am starved when I take healthy balanced meals and snacks of my own. I don't understand it myself. And then there is me, I seem to have this wierd self destruction thing. When everything is going well, the running is on, the diet is working...I pick up a cigarette. A pack of cigarettes. I lose 10 pounds, I celebrate by eating...lots...
I know I do this and cant seem to stop it.
I want to complete a marathon and I think I give myself a way out "just in case" I dont make it by eating or smoking or not doing the training. 38 years of me doing this. Know a good shrink?
So...for my new years resolution: I want to run/walk a minimum of 4 days week. Train and complete another marathon and lose 30 pounds.
And what about you?

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posted Jan-01-2006 08:37 PM            

quote:

---

Originally posted by flynnmcmahon:
Letinerj, thanks, ok so its just my bod being used to something and not a NEED. I'm cool with that. Along
that same line. I am assuming other than before or during
you eat carbs and are NOT a low carb person, Am I correct
there? When you say you are tryingt to keep from melting
away, that of course gives those of us who want to drop
some pounds, hope. Can you give me an idea of a day's
intake and how that works around your workouts?
I know everyone's different, I'm just interested and thank
you again!

---

You bet! No, I'm not a low carber by any definition, nor
a low anythinger! Keep in mind that in peak season, I
was running 70-90 mpw, cycling 100-180 mpw, and swimming
4-6 mpw. I also lift weights, upper body, which I've been
doing for about 20 years, since long before I started running.
If I don't eat a ton with all those cals burned, I lose all of
my muscle and I shrivel up into nothingness. It's taken
a lot of hard work to put my weight back on! When I'm maxing
out my activities, I basically eat all day long. During the week,
for breakfast I'd have about 5-6 "servings" of cereal, usually
frosted mini-wheats or raisin bran with chopped up banana,
about half a gallon of fat-free milk (not that I'm low fat - I just
don't like whole milk), followed up with a couple of Krave bars
or granola bars, which I'll have several times a day. Lunch -
if I'm doing a lunch time bike ride, I'll have a bowl of chili or
soup (generally 2-3 "servings), whatever kind of crackers or
chips I've got in my office, granola bars, cookies, candy bars,
etc. If I'm not riding, I'll have a large burrito or foot long sub,
typically. Peanut butter cups (for the utmost in health food)
are not uncommon. Frequently, I snack on peanuts. Big
dinner of whatever, and sometimes a "second" dinner later.
Big dessert. More snacks. Generally four or five servings
of broccoli and/or cauliflower (not all crap!) More milk. Also,
plenty of empty calories from sweet tea and sodas. Lots
of chocolate. Somewhere between about 8000 and 10000 cals
per day. Are you glad you asked? Now you know who not
to call to be your nutritionist! Post run, I usually will drink 2
or 3 glasses of chocolate milk - I really like the milky way
and three musketeers chocolate milk slammers, so I'll sometimes
have a couple of those after a long run. I really don't pay much
attention - I just eat a lot, try to get in some good fibers, fruits,
and vegetables, try not to overdose on saturated fat, and avoid
trans fat to a great extent. It's a whole lot different from what
I ate 2 1/2 years ago before I was running - lean cuisine,
rice cakes, water, and not much more. 50 lbs heavier,
50 points higher cholesterol (from what?), and gaining weight
on a weekly basis.

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posted Jan-01-2006 10:02 PM            

quote:

---

Originally posted by flynnmcmahon:
Leitnerj! Holy Cripes! I am so glad I asked! That is awesome!
How long ago did it take you to work up to that kind of schedule workout wise? How do you find the time? Do you work full time? So let me get this straight, when you were 50lbs heavier, what were you doing exercise wise? You said you werent running, were you cycling and swimming and just hadnt gotten into running yet? Did the weight drop off as soon as you started running, etc...give it to me, this stuff fascinates me! I have asked a couple questions in this thread, but with so many you probably dont remember me.
I am 5'5, 35 yrs old, around 135, bodyfat mid 25's. On the muscular side. Trying to wean off the heavy lifting a bit and focus on the running again. Its been really hard. I've had back to back illnesses last winter (colds, flu's and such) and just now got over being sick again. Went for a 2 miler the other day and it wiped me out. Didnt wear my HR monitor so I was probably pretty high. I'd like to get back up to 50mpw or more. I was there about 2 yrs ago. Havent been able to get back there since. I struggle with the eat a ton and run a ton or eat a little run moderately to lose weight, HELP! I only wanna drop about 10lbs, no more.

---

I was doing only weightlifting, no cycling, no swimming, perhaps
an occasional 30 minutes on the elliptical or treadmill. Lots of
heavy lifting (benching up to 350 on a good day), squats, etc.,
about 6-9 hours a week. Belly rolled over my shorts. I weighed
about 220. Started running in 7/03. About 400m day one. About
800m day two. A little bit more each day. No tracking of distance,
pace, or time, just running. Ran every day, sometimes twice a
day. A month or so later, I was up to 10, 15 mile runs, without
realizing. A friend told me that I was running 20 miles on one of
my courses and said I should sign up for a marathon, which I
did, and ran it in 11/03, in 4:03. Leg locked up right after I finished,
nasty ITB injury and chondromylacia. Then I started training properly
and tracking my distances. By 10/03 I had lost about 70 lbs, without
realizing it. My wife just suddenly mentioned that my butt had
disappeared (she didn't really like that) and I noticed that I had lost
a good percentage of my strength. At that point, I started eating
a lot (but still less than I do today). Didn't start cycling and swimming
until March of this year, after my bone bruise (slip and fall) injury.
In May I started building everything up to high mileage in preparation
for the Tahoe Triple Marathon and I built it up pretty quickly (the
detailed story is in my running log, if you start late in May when
I started running again regularly.

After my mileage cranked up and got my running going again, that's
when I really had to start eating a lot. I work full time, about 45-50
hours per week, commute to work and home 30-45 minutes each
way. I'm an associate editor for a journal, which takes up another
10 hours or so a week, entirely outside of work. Two kids that
play travel soccer, always in different locations (along with at least
3 other activities apiece). During the week I get up at 5 and run/workout
in the morning before work. In decent weather, I take my bike to work
and ride a 21 mile loop at lunch time, as many days as possible
as long as I don't have a meeting conflict. During a peak training time,
I will sometimes get up at 4 during the week to get extra in and
it's not unusual for me to have to get up at 3 or 4 on Sat and Sun to
get in all of my stuff. In season, I sometimes would get a bike ride
in while my son is at soccer practice, which will give me up to two
hours there. It was not unusual for me to get up at 3 on a Saturday,
go for a 20 mile run, stop in, change my shoes, and then hit a 40-50
mile bike ride, come home, and shower before everyone is awake.
Then there were days where I had to get home by 6:30 to get my son
to a distant soccer game and try to get an extra run or ride in
while they were warming up or between games if it was a tournament.
It may sound crazy and you would think I'd be tired all the time, but
I find that I get more tired the less stuff I do and even if I'm not sleeping
much (I don't usually get to bed before 10:30 or 11, sometimes 12),
I'm much less tired if I get in a lot of running and biking mileage.
Only aerobically. If I did my runs the way I did before starting
heart rate training, I would barely be able to tolerate 50 miles of
running per week, much less half the other stuff. When I cut back
my mileage as I have done the past few weeks after my end of
November marathon (capping off my 6 marathons and 50 mile
race over a 2 months period), I start to get sick and my asthma
and allergies all come back. Hence, I try not to take too much time
off. Now my weight stays steady around 168, body fat around 9%.

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posted Jan-02-2006 07:02 AM         

quote:

---

Originally posted by leitnerj:

Nonetheless, no fat is used for fuel above LT (if you assume that
LT occurs at anaerobic threshold, which by definition is the point
where you hit 100% use of carbs for fuel).

---

Lots to respond to in your post. But starting with this:-

I have always understood LT to be defined as the point where lactate in the blood reaches a certain level - usually 2.5 m/M. It is significant as it marks the intensity where aerobic respiration is starting to ramp up. That's basicaly it - no mention of the amount of fats burned. Could be conicident of course, but the article says otherwise. Are there other more recent references?

posted Jan-02-2006 08:26 AM            

quote:

---

Originally posted by briandirect:
Lots to respond to in your post. But starting with this:-

I have always understood LT to be defined as the point where lactate in the blood reaches a certain level - usually 2.5 m/M. It is significant as it marks the intensity where aerobic respiration is starting to ramp up. That's basicaly it - no mention of the amount of fats burned. Could be conicident of course, but the article says otherwise. Are there other more recent references?

---

Well, what you are really pointing out is the fact that I am ignoring your
use of the term lactate threshold and performing a bait and switch with
the anaerobic threshold. The anaerobic threshold is the point where we
hit 100% carb use for energy. There are many definitions for LT, the
one you point out being a common one. However, it is a fact that
they are generally going to be very close together (to where for all
intents and purposes they happen at virtually the same heart rate and
the same properties are present). Some will consider them the same
thing (e.g., http://www.rice.edu/~jenky/sports/anaerobic.threshold.html)
and some will be very careful to distinguish them and adamant about
their proper use (e.g., http://www.roble.net/marquis/coaching/billat.html)
but my favorite site for all of this type of information is http://home.hia.no/~stephens/running.htm
In my opinion, the anaerobic threshold is the most direct parameter
that is associate with the cutoff between the aerobic and anaerobic
systems. Nonetheless, given that the high onset of lactic acid
accumulation occurs very close to the point where you transition
to 100% carb burn for energy, I make the stretch that when you
train exclusively at low heart rates, you won't do anything to
improve your performance above lactate threshold, and further,
your capability there is likely even to decay. For one that is not
worried about the distinction between the aerobic and anaerobic
systems, the anaerobic threshold is a useless quantity. There's
nothing magic about it because for heart rates 5, 10, 15 beats,
and much more below (for most people), most of the properties
will be anaerobic anyway (mostly carb for fuel, fast twitch muscle
fibers being employed).

By the way, a bit of a diversion here - I'm glad runawayjesse
prompted me to dig back into the vault and take another look
at Hadd, which I hadn't done for a while (http://www.ffh.us/cn/part1.htm).
It reminded me of the key thing that indicates a lack of aerobic
fitness. It's not so much whether McMillan's (or similar) pace
calculator works for you, it's whether there is a clear relationship
between your paces at all distances, assuming you have properly
trained at the specific distance. Certainly your pace gets slower
for longer and longer distance races, but it should follow a fairly
regular geometric pattern. The relationship is that one should be
able to reduce pace by ~16 seconds/mile, in order to double the
race distance. For very well trained athletes, the 16 may go down
to 12, 13, or 14. It may get higher for others (perhaps if they weigh
more or something). So, if one runs a half marathon in about 1:30
(around a 7:00/mile pace), they should be running the full marathon
at about a 7:16/mile pace, or about 3:10. Or for that runner, the
magic number may be 18 seconds, and that ~18 seconds should
cover the relationship all the way out from a one mile race, if you
were to keep doubling the race distance.

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posted Jan-02-2006 09:17 AM         

quote:

---

Originally posted by leitnerj:
[B The anaerobic threshold is the point where we
hit 100% carb use for energy.

[/B]

---

There is no actual transition point. It's just that at the so-called threshold the aerobic system is rapidly ramping up to meet more and more of the growing energy demamnd.

posted Jan-02-2006 09:50 AM            

quote:

---

Originally posted by briandirect:
[QUOTE]Originally posted by leitnerj:
[B The anaerobic threshold is the point where we
hit 100% carb use for energy.

---

There is no actual transition point. It's just that at the so-called threshold the aerobic system is rapidly ramping up to meet more and more of the growing energy demamnd.

[/B][/QUOTE]

Any place where you can find the relationship between respiratory
quotient and anaerobic threshold will tell this story, such as
http://www.lakesidepress.com/pulmonary/books/physiology/chap12_1.htm

You might also find this discussion interesting:
http://www.fact-canada.com/discus/messages/13/38.html?1105839224

Now, as I was digging around, I came across this article:
180-age seems to be a Maffetone-derived site.

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posted Jan-02-2006 10:27 AM         

quote:

---

Originally posted by leitnerj:
At
85% vo2max, which corresponds to a heart rate of 160 for me,
I'm at about 65% carb/35% fat,

---

Question mode continues, I am afraid.....

Could you perhaps verify that your figures are right? I am trying to reconcile %VO2max with %max HR. References write that %VO2max is the lesser figure.

For example I found the following formula:
%MHR=0.64 × %VO2 Max + 37

So the calculation would put 85% VO2max above LT - at 91.4% maxHR.

-brian
http://www.brianmac.demon.co.uk/maxhr.htm
http://www.rice.edu/~jenky/sports/hr.html

posted Jan-02-2006 10:42 AM            

quote:

---

Originally posted by briandirect:
Question mode continues, I am afraid.....

Could you perhaps verify that your figures are right? I am trying to reconcile %VO2max with %max HR. References write that %VO2max is the lesser figure.

For example I found the following formula:
%MHR=0.64 × %VO2 Max + 37

So the calculation would put 85% VO2max above LT - at 91.4% maxHR.

-brian
http://www.brianmac.demon.co.uk/maxhr.htm
http://www.rice.edu/~jenky/sports/hr.html

---

The formula you quote above is similar to a 220-age formula - very
large variance. Nonetheless, you need to be very careful (and wary)
of anything that is tied to max heart rate, for reasons that I've mentioned
earlier - max heart rate is not only exercise specific, it's distance
specific. In my first vo2max test in February, I did no warm-up first,
and my max heart rate came out to be 190 (at the point of total
exhaustion). In my test more recently, it peaked out to 195 (I did a
10 minute warm-up jog before this time). In races greater than
10 miles but less than 20, I regularly (at least a dozen times) achieve
and sustain heart rates greater than 200 and peak out at 210.
Nonetheless, I'll give you the raw numbers:

max heart rate ever achieved this year: 210
max heart rate during recent vo2max test: 195
vo2max in most recent test, 62.5 @ HR of 189
anaerobic threshold HR: 177
rest heart rate day of test: 38

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posted Jan-02-2006 10:47 AM            

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posted Jan-02-2006 01:37 PM         

quote:

---

Originally posted by christa0120:
***Barge***

I used to train with my HR in the 155 range.
I am now only doing the 137-147 range. (although now I am trying MAF and going for under 142.
I just did 1 hr 20 minutes with no need for anything. Before I required Gu or gatorade to help me plug along...and I was in better running shape before, or atleast I was more consistant.

---

If you run late in the day, make sure you ate well during the day, but not within 2 hrs of your run. If you run in the morning, make sure you ate well the day before. You definitely shouldn't have to take in carbs for an easy run of less than 1-1.5 hrs. If you must take in something do it after your first 30min and wean yourself like Jesse recommended. The impact on your fat vs carb usage is less if you're already running than if you eat before your run.
 

posted Jan-02-2006 01:57 PM            

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posted Jan-02-2006 02:06 PM         

quote:

---

Originally posted by briandirect:
[QUOTE]Originally posted by leitnerj:
[B The anaerobic threshold is the point where we
hit 100% carb use for energy.

---

There is no actual transition point. It's just that at the so-called threshold the aerobic system is rapidly ramping up to meet more and more of the growing energy demamnd.

[/B][/QUOTE]

You're right, it isn't so much of a threshold as a transition point. I've seen LT, described as the point above which you are producing lactate faster than you can clear it out. At just above LT, the rate of accumulation slightly exceeds clearance rate and you can run for a while. At 100m sprint speeds, it far exceeds your ability to clear it and you'd lock up pretty fast.

If I'm not mistaken anything under a half marathon is usually run above LT. A marathon is run just below LT. This is why a big part of marathon training is aimed at pushing up your LT, so you can run at higher effort for longer and be more comfortable doing it.

LT is related to fat/carb ratio only in that above LT you are using both aerobic and anaerobic systems and the latter can't use fat at all. While at strictly low efforts you are only using the aerobic system and can use majority fat v carb. Although when training strictly aerobically, you are always burning a combination of fat and carbs. In fact, you can't really stress the fat burning system without using carbs.

--jm
 

posted Jan-02-2006 02:30 PM            

quote:

---

Originally posted by junkmiles:

LT is related to fat/carb ratio only in that above LT you are using both aerobic and anaerobic systems and the latter can't use fat at all. While at strictly low efforts you are only using the aerobic system and can use majority fat v carb. Although when training strictly aerobically, you are always burning a combination of fat and carbs. In fact, you can't really stress the fat burning system without using carbs.

--jm

---

Yup. But, on the contrary, I believe over anaerobic threshold
(which some consider slightly different from lactate threshold),
I believe everything is fully anaerobic, no oxygen being used
and all carb being used for energy. The two vo2max tests I
have had done, from different organizations, both define AT
as the point at which RQ = 1 and hence all energy is from carb.
Neither identifies a lactate threshold, probably because, there
are no actual blood lactate measurements and hence it can't
be determined exactly. However, O2 and CO2 intake and
exhaust are measured precisely.

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