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Does nutrition really matter?

There are some people who think carrying around a bottle of filtered water all day make

them healthy. This practice may make the person healthier than if he/she did not do it,

but it does not necessarily make them “healthy” if they also smoke a pack of cigarettes a

day. On the other end of the spectrum, we all have that friend who eats (or even drinks)

whatever he/she wants and still does well on the bike. However, some people are given a

great set of genes, and no matter what they do, they will still do well. Doing well despite

a poor diet, however, does not mean that the person is doing as well as he/she could.

This particular column will give you a little perspective on the importance of nutrition for

cycling performance. Although nutrition by itself will not make you better than you

really are, without proper nutrition, you will not live up to your potential.

The basics of human adaptation are that you stress the body, the body senses the stress,

and the body takes appropriate steps so that the next time the stress is imposed, the body

is better suited to deal with the stress. The “appropriate steps” the body takes has to do

with making proteins. For instance, if you perform a bout of weight training, your body

makes proteins in the muscle that are better suited to generate force so that you can move

that weight easier next time. This example of course is why your muscles get bigger with

weight training. Not so obvious are the proteins your body makes after a long training

ride since there is no physical appearance of those proteins. The proteins your body

makes after a long training ride are the ones that make your muscle better suited to use

oxygen for energy production, e.g. mitochondrial proteins, enzymes, and cell



The application of adaptation to exercise training has been termed the overload principle.

What the overload principle states is that one must apply an appropriate stress to the body

so that the body is not understressed, thus providing no stimulus for adaptation, or

overstressed, causing failure and overtraining. The stress must be specific to the goal

you are trying to achieve and designed for the individual person. “Specific” has many

levels of complexity in cycling – such as we do not go running (regularly) to get better at

cycling, to doing 5 second jumps rather than 3 hours of easy riding to get better at

criteriums. Individuality refers to the fact that all of us adapt to stress differently as a

result of our genes, and therefore what might be right for us may not be right for another


There is one more component of the overload principle that most of us know all to well

and that is reversibility. What reversibility means is that if a stress is not applied for

some time, the ability to deal with that stress will go away; or said another way,

reversibility refers to detraining. A good question is why does the body detrain? Why do

we have to go through all the work of building up resistance to stress again? The answer

has to do with the proteins the body makes to help us adapt to stress. These proteins have

to be built up and broken down to stay in good working order. The process of building

up and breaking down proteins takes a lot of energy. In fact, while resting the making of

protein is the single largest consumer of energy in the body. Therefore, the economics

becomes quite simple, if the body does not a protein for a little while it gets rid of it sothat it does not waste energy sustaining it and can focus its resources on other proteins

that it does need.

As mentioned, the body “senses” a stress. The means by which it senses is beyond the

scope of this column. What is important is that the sensing of a stress sets in motion a

series of events that makes proteins. You may then ask how the body knows what

proteins to make? The search for the appropriate pathways and what turns them on is a

very active area of cellular biology research. For the purpose of this column, though, we

will call these pathways “signaling pathways” because a sensor turns on the pathway and

signals only the correct proteins to be made. For example, when people go to altitude to

train, a sensor detects that there is less oxygen and turns on signaling pathways that make

proteins that will help deliver more of the oxygen that is available. The important point

here is that the body will always sense these challenges and put in to motion the signaling

pathways to take better adapt to the challenge. Specific to cycling, the time spent on the

bike doing long slow rides, sprint workouts, and intervals are the stimuli that are sensed,

and turn on signaling pathways that tell the body which proteins to make so that we may

do those specific tasks better next time.

I stated in the introduction that this column was about nutrition, but I have not yet

mentioned it. Therefore, I want you to think of the processing of building a house.

Suppose you visit the architect and have your dream house drawn up on blueprints. You

then buy the perfect plot of land, stake your lot, and hire all the best contractors. Finally,

the big day comes, the ground is broken and the crew gets to work. Now imagine that

you only had enough money to buy second-rate construction materials, how close will

that dream house really come to its potential? Will it really be a dream house with

inferior building materials? This analogy is really quite simple and obvious, the blue

print is your training plan, the contractors (translates blueprints to a house) are your genes

(translates training stress to proteins), and the construction material is the nutrition

components that build the body’s structures.

I was careful to state above that the signaling pathways tell the body what proteins to

make. However, in the absence of the appropriate building blocks, the body can’t

actually make the proteins. In other words, training sets in motion an adaptive potential.

To take advantage of the potential, amino acids (from protein) must be provided to build

the proteins, and energy (primarily from carbohydrate) must be provided because of the

energy it takes to build proteins. As I write this, my first thought is that people will take

away that eating lots of protein is the most important nutrition modification you can

make, which is wrong. Yes, eating protein is important, but for the endurance athlete

eating enough carbohydrate is still most important. Since the body uses up energy during

exercise, you need to replace it after you are done or you will not have enough energy to

make the proteins you need in your body to adapt to the training. In fact, if you don’t

have enough energy, your body will break down proteins that you may need without

replacing them, because at that point in time, having energy to sustain body function is

more important than maintaining more protein. Interestingly, scientists have recently

discovered that the amount of energy in the cell is one of the “signals” that determines

what proteins are made and not made. Further, on a day-to-day basis people need toconsider the so-called micronutrients, also known as vitamins and minerals. These

nutrients are important because they make sure all the pathways in the body are working

properly. Therefore, having a well balanced diet is important to make sure that all the

metabolic pathways are working smoothly. The take away message is that by having a

well-balanced diet and providing energy and protein around your training provides the

high-quality building materials and workers to take advantage of the adaptive potential of

your training.

In summary, nutrition is important, and just as nutrition alone can not make you a great

athlete, training without proper nutrition will not make you as good as you could be. I

have to give one more word of caution here to fend off a mixed message – although

proper nutrition is important, more is not always better. In fact more (such as found in

“supplements”) can often be detrimental. In a future column I will address the “why”

behind why more is not better.