How to tap a fat deposit
First, a few words about chemistry, even if this means returning briefly
to the dismal surroundings of the chemistry classroom. One gram of
body fat has seven kilo-calories of potential chemical energy, or seven
"calories" for short.In comparison, one gram of glucose has only four
calories. Energy, whether from fat or glucose, is released for use when
the molecules are subdivided into their individual components. To put it
another way, energy is released when^high-energy molecular compounds
are broken down into their low-energy building blocks. This is exactly
what happens in the power plants - with the help of oxygen. Now you
know where the energy to run comes from.
Let's take a look at the compounds of glucose and a special fatty acid
called palmitic acid. Glucose is C8H12O8; palmitic acid C15H31COOH.
To be honest, these formulas mean absolutely nothing to me, and since
you too may have trouble interpreting the full meaning of these hiero-
glyphs, we'll do something that was strictly forbidden at school. We'll
delete everything that looks hostile and confusing, namely all those
subscript digits and duplicate letters. What we wind up with is clear
and straightforward: C, H, O - carbon, hydrogen, oxygen. These three
substances form the fuel that gives our body its strength.
As you can see, it turns out that our two main energy suppliers - fat and
glucose - have identical components. Both are made up of C, H, and O.
They differ only in the structure of the nutrient molecules released from
food during digestion. It's worth noting that, in principal, it doesn't matter
to your body in the slightest whether its energy comes from fat or glucose.
I can well imagine what some of you are thinking. You want to know
whether running tends to burn off fat, or whether the power plants prefer
glucose, making it harder for you to lose weight. To answer this question,
we must step back and look at the larger picture. Fats cannot be burned in
our metabolism without oxygen. Glucose, on the other hand, can. As long
as there is enough oxygen in the incinerators, the power plants will prefer
fatty acids, which they normally take from the bloodstream. There is good
reason for their preference for fat over glucose. Our muscle cells are not
dumb. They know that if there is a sudden upsurge in energy requirements,
e.g. to run at high speed, their power plants will not have enough oxygen
on supply because the runner, if he or she runs too fast, will soon be out
of breath. Once the oxygen supply is cut off, the only thing the cell can
burn is glucose. And because the cell also knows that the supply of glucose
in the glycogen stores is limited, it will save these reserves for a possible
"red alert": anaerobic consumption.
Perhaps you've heard already that marathon runners and triathlon specialists
tend to gorge themselves on spaghetti the day before a competition. They do
so because they need to fill their glycogen stores to the brim if they want
enough energy reserves for their many little "red alerts." These athletes are
always straddling the border between aerobic and anaerobic consumption,
and always cross it for short periods of time. Being a novice, you will spend
most of your time on the wrong side of this border, and will often switch to
"red alert." Before long, your glycogen stores will be plundered - and the fat
cells spared. A brisk walk would leave enough oxygen at your disposal so that
your body would only consume fats. The problem is that a brisk walk doesn't
require much energy from your muscles, so it's useless as a means of reducing
body weight. Your organism is familiar with the load placed on it by a brisk
walk. What it doesn't know is the higher load caused by a slow run.
Not until your organism has adapted to this load, so that jogging poses no
more difficulties than a brisk walk, will you be able to burn off more and
more fat. Now, at last, you can begin to tap your fat deposits. In other words,
it can't simply be taken for granted that you gain energy by burning fatty
acids. Yet another adaptation is required, and it can't be expected to occur
in your first few days of jogging. Those who think that a couple of days of
running will suffice for a visible loss of body weight are fooling themselves.
It's a biological impossibility.
If weight reduction is your second major target in running, you should take
a long, hard look at this next sentence: "If, and only if, I run regularly, I will
train the ability of my muscle cells to prefer fats as fuel." A bit convoluted,
perhaps, but worth committing to memory.
(C) 2005 - Alle Rechte vorbehalten