> Dr. Andrew B. Chung, MD/PhD wrote nonsense and lies in article
> > >> It seems to me I heard somewhere that Home, Home On The Mu_n wrote in
> > >> >>From the formulas I cited, five miles will burn between about 500 and
> > >> >>about 550 total calories, depending on speed.
> Chung Much too simple. many more factors involved in computing work.
Not at all too simple. Very accurate in fact. But more on this
> Kirkman I'll stick with the formulas used in training athletes, weight
> > >> activities, and similar fields. No "computing" work going on here, just
> > >> application of empirically derived formulas from those in the business.
> Chung Your choice. I prefer the truth, which is that average folks
> can at
> > >most hope for about a threefold increase in their metabolic rate from
> > >the basal rate with aerobic exercise.
You do not prefer the truth. You prefer lies you have deluded
yourself into thinking are the truth. More on this later.
> Kirkman Your commentary seems to imply that it invalidates the
> formulas used by
> > exercise physiologists and trainers.
> Chung Those formulas are notoriously inaccurate.
Notoriously accurate would be the correct statement.
> Kirkman Since the truth of such an
> > implication is not self-evident perhaps you could offer some facts, a
> > logical explanation, or some cited sources to support your opinion.
> Chung It is well recognized that oxygen consumption (VO2) is the most
> measure of metabolic rate (rate of calories being burned... i.e.
> This can be confirmed experimentally by giving you cyanide thereby
> your mitochondria (where oxidative phosphorylation happens).
This is not how cyanide kills you. You are dead long before any
meaningful amount of cyanide has a chance to reach the mitochondria in
your muscle cells. Did you not have to take any science in college
Chung? Or have you simply forgotten all of it you took?
> VO2 goes
> to zero, so will your metabolic rate (i.e. you will be dead).
> A person's maximum VO2 (VO2max) is known to match a person's maximum
> rate of
> For a background review on this topic:
> From clinical research, we know that VO2max during exercise generally
> when a person's heart rate reaches the predicted maximum heart rate
> (PMHR). We
> also know that any percentage of PMHR correlates quite well with the
> same given
> percentage of VO2max.
> So for some real life examples:
> I am 39 years old. My predicted maximal heart rate (PMHR) is
Your formula for max heart rate is useless. For instance I will use
myself as an example to show how foolish this formula is. I am lots
older then Chung claims he is. His formula says my max heart rate
would be about 150. Yet only a couple of years ago my doctor had me
on a treadmill and asked me to tell him when I had two minutes left in
me. He decided to stop the test at a heart rate of 185. I do not
know why. I had not told him I was down to two minutes.
Further, max heart rate is not the point at which anyone can exercise
on a sustained basis. At max heart rate you are well into anerobic
metabolism and building lactate in your muscles rapidly. I probably
have only been to max heart rate a couple of times in my life. Let me
tell you what max heart rate feels like. Your legs are lead. Your
leg muscles are burning badly from lactate buildup. You have a
roaring noise in your ears. But you probably do not notice it because
of the pain and the fact your brain is not working very well due to
oxygen shortage. Your vision is getting bad fast. The couple of
times I might have hit heart rate max were the last 50 yards of a race
back when I ran competitively. I had no memory of the last 50 yards
or hitting the tape after the race.
The aberant diet Chung eats and his total dismissal of any exercise
program makes me sure he has never come close to heart rate max. If
he did there is a decent chance he might not live through it.
What level can a person exercise at for a extended period? Simple.
It is called the lactate threshold level. This is the point at which
you just start to make lactate. Depending on all kinds of factors,
including training, the lactate threshold level is from perhaps 60% to
85% of a persons max heart rate. I would expect from what Chung has
told us about himself he could not sustain a heart rate above 60% of
his heart rate max. That would be perhaps 130 bpm. Maybe less. By
contrast, my lactate threshold heart rate is about 165 or 170 beats
per minute. Note that this rate is HIGHER then Chung's nonsense
formula says my max heart rate should be. So much for the formula.
> Right now while sitting here typing this, my heart rate is 60 bpm.
> This means that my VO2 is probably about 33% of my VO2max. This also
> means I
> am burning calories at about a third of my maximal rate. If my
> metabolic rate is 75 kcal/hr (pretty reasonable guestimate), then when
> I walk
> on a treadmill and get my heart rate to my PMHR of 181 bpm, I would
> a metabolic rate of three times that or 225 kcal/hr.
The above is so filled with falsehoods it is hard to know where to
start. First of all, as I have pointed out above Chung can not
possibly perform at a sustained heart rate of 180. Thus his factor of
three is too high right off.
Then there are the built in assumptions about pump volume. Chung
assumes that a persons heart pumps the same volume of *** regardless
of its rate. This simply is not true. As a persons heart speeds up
it may pump less *** per beat, essentually the same volume per beat,
or an increased volume per beat. Which it does depends on a whole
host of factors ranging from disease to genetics to training.
Also Chung makes the invalid assumption that the bodys oxygen uptake
of a given volume of *** is invarient with increased exercise
levels. This is also not what science has shown.
Thus his simplistic math has no relation to reality. It is a pure
figment of his imagination. In fact if you believed what he says and
simply factor in the limits due to his lactate threshold level he has
proven he can only exercise at a factor of two greater then his
resting metabolism level. Even he can do better then this.
> Kirkman How does increased metabolic rate from exercise relate to the
> > energy expenditure derived from the formulas? Do you mean metabolic
> > rate *during* exercise, or increased basal rate as a result of
> > consistent exercise over time? So far the thread has been about calorie
> > burn during bouts of exercise--going back to a widely used approximation
> > of a burn of approximately 500 during a five mile walk or run.
> Chung I believe what I have written above answers your questions.
Lets think a little bit about the physics of running. At the normal
speeds people run distances, say up to 12 mph, frictional drag from
the air is nil and can be ignored. Any undergrad science student can
easily prove this based on simply physical propertys of air and the
size of our bodies.
So where does all the expended energy go? Well, consider the
mechanics of running. At shortly after the time your farward foot
hits the ground your center of gravity is at its lowest. You then
raise your center of gravity as your leg comes under you and pushes
back. For a moment after your back foot leaves the ground you are in
free fall before your other foot contacts the ground ahead of you. So
essentually, the act of running involves falling forward with a
lowering of your center of gravity followed by lifting your center of
gravity back to its max point. Most of the energy to run is involved
in this lifting of your center of gravity back to its high point.
People who run slow do not do so by taking fewer steps per time
interval. Slow runners take the same number of steps per minute as
fast runners. But fast runners take longer steps. Thus, over an hour
a slow runner must lift himself less distance vertically then a fast
runner. Thus the slow runner will burn fewer total calories per hour
then the fast runner. But if you calculate how many calories each
burn to run a mile according to Newton's laws you find that both burn
the same per mile. A bit under 100 cal burn is a good average number.
This depends of course on the person weight and physical dimensions.
The person also burns some calories maintaining the rest of his bodily
functions. So total calorie burn is a bit over 100 per mile.
Does all this seem rather complicated? I am sure it is far too
complicated for Chung to understand. I am sure he will tell us Newton
was wrong. But just think about this for a moment. Think about how
easy it is to run down even a small grade versus running on the flat.
Why is it so easy to run down a slight grade? Because you are lifting
your body less is why. And how much harder is it to run up that
slight grade then on the flat? It is a lot harder because you are
lifting your body a lot more on an uphill grade. Even a drop or rise
of only 1 foot per 100 foot horizontal is very noticable. Even Chung
will have to admit this if he has ever actually seen treadmill
To further illustrate how important lifting your body is when running
consider what it is like to ride a bicycle. Depending on the bike and
terrain I am told that a bike is some 5 to 7 times more efficient then
running from an energy expendature standpoint. What is the big
difference? On a bike you do not ever change your bodies center
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