WARNING: Doing Cardio In A Fasted State Causes Muscle Loss & Fat Gain

October 18, 2019 0 By William Morgan

The other day I got asked the following question:
Dr. Sam – I want to lose fat and gain muscle.
I’m doing intermittent fasting and sometimes
a ketogenic diet.
However, my question is about doing cardio
on an empty stomach, first thing in the morning.
I hear it’s the best way to lose fat – can
you please tell me the real truth?
This is a great question because it’s a
very popular topic and one that I used to
believe in myself, when I was younger.
For years, many experts will tell you that
the best way to lose fat is to do cardio exercise
first thing in the morning, on an empty stomach
after an overnight fast.
The “theory” for this is that your glycogen
stores were depleted during your sleep.
So, there was no “sugar” or “carbs”
to burn off and thus, the cardio exercise
would go directly into fat burning mode.
So you’re saving time and burning more fat.
However, doing cardio after a meal or when
your not depleted, means that you FIRST have
to burn off all the sugar, before you can
go into burning off the fatty acids.
So, this meant that the cardio session was
just burning off the food you ate, NOT actually
burning off body fat.
It wasn’t very efficient.
And guess what, this made perfect sense to
So, years ago, I would get up in the morning,
after not eating for at least 8-10 hours.
I’d drink some water and then go for a jog
or head on over to the gym and do some incline
treadmill or ride the bike or something similar.
I’d do this for at least 30 minutes and
work up a nice sweat.
Plus with the extra endorphins from the intense
cardio, I was super energized and happy.
It was a natural high.
I felt great.
It was a nice way to start the day.
Then I’d come home, I’d take a shower
and I’d wait about an hour before I’d
eat, so the “fat burning” from the cardio
session would continue.
And the good news is that I did lose weight
and I lost it quickly.
Unfortunately, I lost a lot of muscle in the
Looking at just the scale, I was kicking ass.
I was losing weight.
But looking in the mirror, how my clothes
fit and how I was performing in the gym when
lifting weights – well, for sure I was losing
I was slowly getting smaller and weaker.
In 2 months, I lost about 10 lbs … But looking
in the mirror, it looked like I only lost
2-3 lbs of fat.
I looked flat, stringy, and basically, I had
that dreaded “skinny/fat” look.
So I figured maybe I wasn’t eating enough
food, so I increased my calories.
The weight loss stopped, but I didn’t look
any better.
The bottom line was that I lost weight, but
a lot of it was valuable muscle.
So, why did this happen?
Did I do something wrong?
Well, the reason is that the cardio was stressing
my body.
It was too intense.
I had no food in my system, so my body thought
something must be wrong.
He’s hungry and he’s running away from
So, it wants to protect and it goes into survival
It increases stress hormones, such as cortisol.
It’ll then lower thyroid levels, to slow
down your metabolism.
It also messes up with your sex hormones.
I know this for a fact because I started doing
both saliva and blood tests to see what was
going on.
My cortisol levels were like double the high
And, my testosterone had dropped in the process
as well.
And there were other negative changes in other
And over the years, I’ve seen this happen
over and over again with other people.
And it happens to certain people and body
types much worse.
Women for example, lose muscle more than men
doing intense cardio in a fasted state.
Skinnier, “ectomorphs” for sure lose a
lot more muscle, as well.
People who lift weights, lose muscle as well.
The people that can do intense cardio in a
fasted state tend to be genetically muscular
people – mesomorph or endomorph who put on
fat quickly.
Also, people taking steroids can get away
with this easily.
So, knowing what I know now, I would do things
I would NEVER do intense cardio, any time
of the day.
This means NO running, jogging, biking, etc.
Only a few genetically gift people can do
this and not lose muscle.
If you want to do cardio in a fasted state
in the morning, that’s fine.
But do a 15-30 min brisk walk.
Just enough that your breathing hard, but
you can still carry a conversation.
NO intense cardio, running, jogging, etc.
Instead of doing long cardio sessions, such
as 30-60 min brisk walks, it’s best to do
multiple smaller sessions.
For example, 10-15 minutes, 3x daily.
Before or after a meal.
Doing the above will allow you to burn more
fat, NOT lose muscle and most importantly,
turn on your fat burning hormones and increase
your metabolism, all day long.
It’s easier to do.
It’s less stressful.
You can do it any time, any place and it won’t
cost you anything.
More importantly, it won’t screw up your
hormones and accelerate aging.
And if you want more details about how to
naturally turn on your fat-burning hormones
all day long, make sure you visit the link
below this video, in the description area.