Pro #3: Fasted morning
cardio could lead to an improved fatty acid mobilization during
exercise and increase insulin sensitivity afterwards. This might be
true of exercise at a low level of intensity (50-75% of max VO2) since
this decreases insulin levels via the stimulation of adrenergic
receptors. A lower insulin level can increase fatty acid mobilization.


However,
a higher intensity of work (above 75% of max VO2) can actually have the
opposite effect. So in that regard a moderate or even low intensity of
work would seem to be superior in the morning as far as fat
mobilization goes. (Galbo, 1983, Poortmans et Boiseau, 2003)

To counterbalance the reduction in insulin production during exercise
at a moderate intensity, insulin sensitivity is increased, especially
in the muscle. Since insulin sensitivity is already high in the fasted
state, morning cardio could allow you to significantly increase
glycogen storage and reduce the storage of carbohydrates as body fat.

So
in that regard, morning cardio in a fasted state could increase fat
loss during a cutting period and allow a bodybuilder in a bulking phase
to significantly increase his carb intake without gaining more fat.

T-Nation: Okay, all that sounds good, so what are the cons?

Thibaudeau: If
fasted state cardio could potentially increase fat mobilization, it's
also potentially more catabolic to muscle tissue. This is due to an
increase in cortisol production during fasted exercise. Since cortisol
levels are already high in the morning, this could lead to more muscle
wasting than during non-fasted cardio.


In
fact, cortisol levels could increase muscle breakdown and the use of
amino acids as an energy source. This is especially true if
high-intensity energy systems work is performed. If an individual uses
lower intensity (around 60-65% of maximum heart rate), the need for
glucose and cortisol release are both reduced and thus the situation
becomes less catabolic.

I personally do believe in the
efficacy of morning cardio, but not in a completely fasted state. For
optimal results I prefer to ingest a small amount of amino acids
approximately 15-30 minutes before the cardio session. A mix of 5g of
BCAA, 5g of glutamine (yeah, I know that Dave Barr won't agree with me
on this!), and 5g of essential amino acids would do the trick in
preventing any unwanted muscle breakdown.

However, I'll
also play devil's advocate and say that morning cardio won't be
drastically more effective than post-workout or afternoon cardio work
when it comes to fat loss. Personally, I prefer to split up my cardio
into two shorter sessions (morning and post-workout).

T-Nation: Interesting. Now let's hear what Berardi has to say.

Dr. John Berardi: Geez,
is there much left to say? These guys hogged all the sciency sounding
arguments so I'll just shoot straight and to the point.


I
wish there were a simple "good or bad" answer to this question, but
there isn't. Things are never this simple. After all, I believe that AM
cardio performed on an empty stomach is incredibly awesome for fat loss
in certain situations and should be avoided at all costs in others. How's that for an answer?


Here are the circumstances in which I think fasted cardio is awesome and in which I think fasted cardio isn't so awesome:


• AM fasted cardio should be done when you're only interested in body comp and you have either a mesomorphic or endomorphic body type.


• AM fasted cardio should never be done when you're an anaerobic athlete requiring strength and power or you simply have an ectomorphic (naturally skinny) body type.


To make it even simpler, here's a chart to determine if AM fasted cardio is for you:

Is AM fasted cardio for you?	YES	NO
You're an ectomorph		X
You're a mesomorphic strength/power athlete		X
You're an endomorphic strength/power athlete		X
You're a mesomorphic bodybuilder/exerciser	X
You're an endomorphic bodybuilder/exerciser	X

T-Nation:
Good points, JB. Okay, that was a lot to absorb. Does anyone have any
comments or brutal attacks on the other experts' answers?

Dr. Lowery: First
a brutal attack: Dave Barr is an insulin-oholic. Forget Alcoholics
Anonymous (AA), he should start IA for size-crazed bodybuilders who
can't get away from their obsession to take up more space at any cost.
But what do you expect from a guy who lives on Pop Tarts?


Okay,
enough slamming. Actually, David is a very bright, very cool guy and I
identify with his need for size. I'd personally be hesitant though to
indulge in large amounts of protein while attempting to perform mild
cardio in a mostly-fasted state.


Proteins are
certainly insulinogenic, even if there's co-stimulation of glucagon.
That creates the risk of body fat protection prior to our uphill
walking. But David wants to spare muscle at all costs (even if it's
potentially slowing fat loss) so I do know where he's coming from! It's
just interesting to see our individual perspectives and how they affect
our reasoning.


Christian and I are on the same
page, I think. I admit that I too have turned to 5g glutamine and/or a
few grams of protein out of muscle preservation paranoia. Can I prove
that it helps? Nope. But the underlying physiology is convincing. It's
like the argument as to whether early AM cardio (or longer duration
cardio) is really superior to other types. You won't find it in the
literature, but biochemically it's compelling. I want to torch fat directly.


Lastly,
I think John summarized pretty well what we've all been saying. The
choice of fasted cardio is relative to goals, intensity, and even how
we define "fasted" (i.e. a few grams of protein looks helpful in the
early waking hours). I agree that no bodybuilding-oriented ectomorph in
his right mind should be prioritizing fat loss over muscle
preservation!


I'd reiterate though that there
are indeed performance athletes (e.g. football linemen) who could use
fat-specific weight loss but are nonetheless power athletes of a sort.
These guys could use light to moderate aerobic work/fat loss that
doesn't add to their existing load of two-a-days with the team, with
concomitant weight room efforts.

Thibaudeau: Good
points, Lonman. In regard to the adequacy of morning, semi-fasted
cardio for different types of individuals and situations, I think JB
brings up an interesting point. While I do agree with his general
overview, I'll side with Lonnie's opinion that some performance
oriented athletes can indeed perform AM fasted energy systems work.


Endomorphs
can indeed thrive on morning cardio provided that the intensity and
duration are both reasonable. Performing a low-intensity activity (for
example, walking on the treadmill at 3.0mph with a 10 degree incline at
around 65% of your max heart rate for 30 minutes) will hardly have any
negative impact on subsequent performance and muscle mass.


This
is especially true if a proper pre and post-cardio nutrition approach
is used. Obviously, if the intensity and/or duration are much higher,
then yes, morning cardio can be destructive to performance and muscle
mass.


I personally found that athletes actually
perform better a few hours after a low-intensity/short-duration morning
cardio workout. It could be psychosomatic or due to a "loosening up" of
the body, I don't know. But I've seen it time and time again with my
athletes.


I'm currently training a bodybuilder
who's four weeks out as we're doing this roundtable and he's right at
30 minutes of morning cardio at 65%. He trains four hours later and
he's constantly increasing his front squat and several other lifts.


I'd like to bring up one other point: energy systems work can be detrimental to muscle mass and performance regardless
of the time it's performed if intensity or duration is excessive. This
is why I always prefer to use a split cardio approach. If an athlete is
scheduled for 60 minutes of low-intensity cardio on a day, I'd rather
have him perform two daily sessions of 30 minutes. Morning cardio
allows me to do that without messing up the individual's schedule too
much.


In any case, if body composition is the
goal, I don't recommend ever going over 45 minutes per session unless
we're well below the 65-70% intensity mark (for example taking a long,
slow walk in the woods).


Barr: If
the insulin-oholic whore may have a word... Lonman, I see what you're
saying about proteins stimulating insulin, but there's another reason
why I opted for Low-Carb Grow! before the cardio. That's because it's
very unlikely that the prolonged trickle of amino acids, from the
casein into our blood, will increase insulin levels. Subsequently, it
won't inhibit fat loss! Sweet deal.



As
far as glutamine supplementation goes, it's been shown that 35g of
glutamine a day had no effect on fat loss or muscle mass in athletes
during dramatic short term calorie restriction (Finn et al., 2003).
This study period wasn't very long and didn't involve morning cardio,
but importantly shows that there are no major anti-catabolic effects of
glutamine. The fact that wrestlers were used lends credence to this
study, because they're often the most catabolic dieters around!


More
importantly, I'm still uneasy about the effects of pre-workout
glutamine on fat burning and glucose utilization. After all, glutamine
is readily converted to glucose and could therefore provide energy with
which to hinder fat burning.


Supporting this
idea, a brand new study showed that aside from the differential effects
on insulin stimulation, we might as well use glucose pre-workout if
we're going to use glutamine (Iwashita et al., 2005). Sadly, this study
used a huge dose of glutamine administered via IV, so the data aren't
directly transferable, but it reinforces the gluconeogenic role of
glutamine. In other words, glutamine acts like glucose calories when
consumed prior to morning cardio, and could subsequently inhibit
morning fat burning.


If you're on Fear Factor
and you need to drink a nasty amino acid shake to defeat your
large-breasted opponents, then you should consume glutamine. Otherwise
it doesn't look good for glutamine and morning cardio.


Okay,
that wasn't very PC of me, but Mr. Hyde tends to come out when the
topic of glutamine comes up. As far as the other amino acids acting as
gluconeogenic precursors, I believe that the slow GI delivery will
limit this.

Dr. Lowery: Barr
makes a good point about the gluconeogenic nature of glutamine: it can
raise blood glucose. But then the vast majority of amino acids are
glucogenic ultimately, so we're back to the total dose thing. Hence
taking a few grams of glutamine prior to AM cardio doesn't seem
"insulin risky" when getting serious for a competition. (Not everyone
goes this deep into a diet with concomitant over-reaching in the gym, I
concur.)


I've been reviewing a fair
amount literature lately on amino acid intake (including glutamine) and
body comp changes, so I'm glad you pointed out the short duration
thing. It's a real difference between much research and free-living
athletes that may not benefit for months. Heck, if we do go with acute
data, there's even the one glutamine study suggesting a GH boost which
would be helpful to lipolysis. (Interpret as you wish.)


And
as for Grow!, I haven't seen time course data on that trickle effect
(e.g. slow-acting casein in the blend) but if there's no initial rush
from the whey isolate, it'd be helpful here. Of course, I like the idea
that there is an initial rush of amino acids, followed by the lingering casein effect.

Thibaudeau: As
Dr. L. mentioned, glutamine is glucogenic (it can be used to produce
glucose). However, it comes to a matter of glycemic load. If you're
ingesting 5g of glutamine pre-cardio, at the most this means that 5g of
glucose will be produced (it more likely closer to 2-3g). This is a
very small quantity which shouldn't affect insulin release
significantly. And it certainly won't interfere with body fat
mobilization and utilization.


As I see
it, it's just enough to maintain stable blood sugar levels when
exercising, so it should help protect muscle glycogen stores. This is
beneficial, especially if you have a strength training session planned
later that day.


Anyway, in the morning I
recommend low-intensity energy systems work (around 65-75% of max heart
rate) which should predominantly use fat for fuel. So in that case, any
glucose formed from glutamine shouldn't interfere with fat loss.

Dr. Berardi: Okay
boys, I've gotta elbow in now since you're all wrong! Okay, I'm just
kidding. In all seriousness, I've got four points to make.


1) It's always about body comp.


There are few – nay, very
few – individuals out there that are interested in either muscle gain
or fat loss at all costs. Remember, not even the NFL lineman wants to
sacrifice muscle mass or strength and power to lose some fat. Nor does
the skinny bastard want to lose his cuts in the name of raw, flabby
bulk.


So, with this said, it's important to
conduct any discussion of fat loss or muscle gain with the caveat that,
ultimately, it's optimal body comp that everyone's after.


•
The NFL lineman wants to be a bit leaner without sacrificing muscle
size, strength, and power. (But, remember, in some cases, he doesn't
want to be leaner. His bulk helps plug up the line and create a pretty
big barrier to getting to his quarterback.)

•
The O-lifter wants to be lighter while maintaining or increasing muscle
power (and although the CNS drives the muscle, muscle mass is still
correlated with power).



•
The pre-contest bodybuilder wants to drop fat while preserving muscle
fullness (and this includes contractile protein as well as muscle
glycogen, intramuscular triglycerides, and intracellular water).

• The skinny bastard wants to be bigger while still retaining some degree of leanness – creating a muscular appearance.


The
point? Rarely does a person strive for extreme muscle gain or fat loss
at all costs. He's usually looking for a balance of muscle and fat, a
balance ideal for his sport or aesthetic desires.


In
fact, it's for this reason that we actually measure the muscle:fat
ratios of each of my Olympic athletes and that we put more stock in
these data than the percentage of body fat data. But remember, this
stuff isn't just for elite athletes. The recreational lifter or
bodybuilder is probably more interested in the muscle:fat ratio than
most of my Olympic athletes.


2) Athletes need to use nutrition to drive body comp, not training.


Here's
an important lesson. I teach all my Olympic coaches and athletes that
nutrition needs to be the body comp control variable – not training.
Look at how typical athletes look at body comp. They're out of shape in
the off-season and then they "train their way into shape." Oops,
there's a knee injury. They get fat. Oops, they're tapering. They get
soft. Whew, they can train with high volume/intensity again. They get
lean.


Notice the pattern? Most people use
training specifically to dictate their body comp. This is a mistake. If
they'd learn good nutritional habits and follow them year-round,
adjusting based on training volume/intensity, they'd always be in the
driver's seat of their physiques and would always be able to maintain a
respectable body comp.


So, when it comes to
athletes, I prefer that they train their skill set and sport-specific
energy systems and then recover the rest of the time. Now, recovery
doesn't only mean sit on their asses or sleep. Light exercise can be
considered active recovery. And maybe that's what Lonnie and Christian
mean by low intensity cardio. But we have to be clear – it's gotta be very low intensity cardio.


Yet
I still don't prescribe it for fat loss in my athletes. If my athletes
do this type of low intensity cardio, it's for recovery – if they need
it. If not, they do sit on their asses or sleep. And they control their
body composition with nutrition.

T-Nation:
This is a great point. Applying it to the average guy, I see way too
many people treadmilling their asses off instead of just tightening
their diets. I'd rather choose better foods that live in the hamster
wheel, you know? Okay, JB, lay your next point on us.

Dr. Berardi: 3) What if it's an elite strength/power athlete with a very sluggish metabolism?


In
this situation, we find the balance between eating enough for recovery
and eating enough of a deficit for fat loss. Most often we can find
that balance point with no problem. And still, I don't have to force
any unnecessary physical activity on them – physical activity that
might compromise their performance or recovery.


However,
once in a while, this approach doesn't work. So what do we do? Well, we
focus on increasing what's called "energy flux." As flux is the
relationship between intake and expenditure, we're talking about
boosting both energy intake and energy expenditure to create a new metabolic situation in the body.


4) Recreational exercisers and bodybuilders can and should do things differently than athletes.


As
recreational exercisers and bodybuilders are mostly concerned with
aesthetics, they want to use whatever exercise and nutrition variables
are at their disposal to achieve that optimal relationship between
muscle and fat.


Of course, it bears repeating
that said optimal point will be different for different folks. The
typical recreational exerciser wants to look like Brad Pitt from Fight Club:
moderate muscle, low fat. And the typical bodybuilder wants to look
like Ronnie Coleman: sick amounts of muscle, sick absence of fat.



The
first type of individual, because he doesn't need a crazy amount of
muscle, can afford to do some strength/power stuff, energy system
stuff, and cardio stuff. And as long as he does a certain amount per
week (I typically recommend between five and seven hours of exercise
per week to achieve this look), he can achieve that Brad Pitt look by
eating clean and training with a constantly changing mixture of those
exercise modalities.


The second type of
individual, now that's something else. Because he wants lots of freaky
muscle and less than 3% body fat, he can only focus on strength/power
stuff and low intensity cardio stuff. (The energy system work just
always seems to flatten those big puffy muscles right out). This
individual needs to be super strict with the diet, counting calories,
cycling macros, the whole nine yards. And, of course, it's likely that
drugs will have to play into this situation as well.


So
let me get to the point of this long ramble. The point is that there
are so many sets of goals out there. And for each goal there has to be
a comprehensive nutrition and exercise approach that targets that goal
with the right set of strategies.


Any
discussion of "protein" alone to get a great body is just stupid. And
discussion of "fasted cardio" alone to get a great body is just stupid.
Any discussion of "carbs" alone to get a great body is just stupid. Any
discussion of "heavy lifting" alone to get a great body is just stupid.
It's how all these things fit together that makes or breaks your
progress!

T-Nation: Okay guys, it
looks like the answer here is going to depend on the person's primary
goal and his genetics or natural body type to an extent. But you've
given everyone a lot to think about. The following discussions and
pissing matches should be interesting. Thanks!



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