For the sake of this
discussion, we'll simplify things to a basic level. Other factsheets
will cover physiology in greater detail but for now we will run with
the idea that there are two ways in which we produce power to propel our
bike forward. Aerobic power and anaerobic power. Aerobic
basically means "with oxygen" and anaerobic means "without oxygen".
Anaerobic power, as we've already established is the
power produced without the requirement for oxygen to be present.
Sprinting, at the end of a race, is predominantly an anaerobic activity.
And as you all know power at these intensities can only be sustained for a
short period of time. But why?
The answer lies in the energy
systems and pathways used to create the power that propel our bikes.
Sprinting and other high energy outputs, attacking, jumping gaps etc, are
powered by the ATP-PC energy systems. The ATP system (Adenosine
Triphosphate) is sustainable for one to four seconds and the PC system
(Phosphate Creatine) will power the anaerobic activity from four seconds
until the PC system runs out; which is possibly up to twenty seconds in well trained athletes.
A graphic example of the
exhaustion of the ATP-PC energy systems can be seen at the end of a race
with a long sprint. When the sprint starts from a long way out the
one's who didn't preserve their ATP-PC systems, or never developed them in
the first place through proper training, are the ones going backwards.
ATP is stored in our muscles and is, basically, fuel produced from
the food we eat; our muscles can only produce energy by burning this
fuel. When Adenosine Triphosphate is used to produce energy it loses a phosphate
molecule and becomes Adenosine Diphosphate. A bit heavy but the
diagram below should explain it a bit better.
We have enough ATP to last us a
few seconds. When it's all gone the muscles start looking for
phosphate molecules and it finds them in the Phosphate Creatine system.
The lonely single phosphate molecules in the PC system (the P in the
centre of the diagram) are introduced to
the ADP (two molecules) system at the bottom and hey-presto we have ATP (three
molecules) again at the top ready to produce more energy.
But not for long, the PC system will become
exhausted normally quicker than we would like.
Once the PC system is gone,
it's gone. The body then looks to the glucose stores to provide power. When glucose is used as fuel, in the absence
of oxygen, we get the dreaded lactate.
When the lactate builds and becomes debilitating we must cease anaerobic
activity and allow our energy stores to refresh.
Depending on the
training you've undertaken, ATP-PC refresh could take one to two minutes.
The recovery from a full on glycogen-depletion bonk, will take a lot,
30 Seconds Energy Flush To find out for yourself exactly how it feels,
find a small, quiet hill and hit it from a standing start in a big gear.
Sprint as hard as you can and keep going for a full 30 seconds.
Here's a video, taken on the
bumpiest road in Jersey, of how it
And here's the thirty second power profile from the clip above.
You'll find a full explanation through following the link at the bottom
of the page.
A simple thirty second test,
with power measuring equipment, on the road or on a turbo,
will enable you to measure and evaluate your anaerobic capacity.
test protocol itself is simple but it is probably one of the hardest and
most physically demanding tests you will ever undertake.
A Wingate Test will allow
you to feel the ATP draining from your muscles and feel the PC cycle kick
in. Then, as the energy systems become depleted, you feel the lactate
accumulation begin. The next ten seconds become the longest
ten seconds of your life.
The results of the test allow
valuable information to be gained regarding your anaerobic capacity and
the physical capabilities of your energy pathways. Devising a
training plan with the specific requirements of addressing the limitations
of your anaerobic capacity is a fantastic investment in your training
Through increasing your
anaerobic capacity you can make significant improvements in the efficiency
of your aerobic engine thus allowing you to cruise at a faster
speed. Then, when you need your anaerobic energy systems, for the big
sprint, you'll find you can sprint harder, faster and longer. And
that's what wins races.
You can find a training drill
to help you develop your anaerobic capacity right here...