The real value of protein
By Ilana Katz, M.S., R.D., L.D. - For
A typical problem for athletes is that they lack
the stored energy required for quality training. A contributor to this problem
is the common misconception that protein is a good primary fuel source for
strength training, muscle building and intense exercise.
It's difficult to find a body builder who
doesn't rely on some form of protein or amino-acid supplement, and attributes
their success to these products. These athletes in particular consume much
more protein than they need.
Because this higher-than-necessary consumption
of protein can offset the intake of other essential energy nutrients
(carbohydrates), it's not surprising that many athletes struggle with low
energy during a workout.
All nutrients (carbs, protein, fat) get
converted to energy in the form of adenosine troposphere (ATP), but each
nutrient has unique properties that determine how it gets converted to energy.
It's important to clear up the misconception
that protein is a ready source of energy, and uncover the real value of
Carbohydrates: Efficient energy
Carbohydrate is the main nutrient that fuels
moderate to high-intensity exercise. Fat fuels low-intensity exercise for long
durations. Once stored carbohydrate is used up, glycogen depletion occurs --
more commonly known as "hitting the wall" or "bonking."
During exercise, this can be avoided by simply
replenishing carbohydrate stores (eating easily-digestible carbohydrates
during exercise that lasts more than 90 minutes). But glycogen depletion can
also occur after several days of limited carbohydrate intake -- it's like
going into your workout on an empty tank of fuel.
Limiting carbohydrate intake forces the body to
rely on fat metabolism for energy production, which is far less efficient and
will limit performance. The main function of protein is to maintain and repair
body tissues and isn't normally used to power muscle activity. But if carbs
and fat aren't available, then the body will rely on protein as a last resort
in order to satisfy energy requirements.
Protein balance and overload
Dietary protein is comprised of building blocks
called amino acids. Once dietary protein is broken down into amino acids, they
join together to synthesize the particular protein the body needs such as
hair, nails, hormones, enzymes and muscles. The liver is the central
processing unit of protein, monitoring the needs of the body and synthesizing
the particular proteins from the amino acids.
The by-product of protein synthesis is nitrogen
in the form of ammonia (NH3), which is converted to urea by the
liver and extracted from the body by the kidneys in urine.
The consumption of too much protein has a
negative impact. As ammonia builds up it's removed as urea, which offsets the
pH balance of blood causing an acidic environment. The kidneys have to work
overtime, using fluids to flush the nitrogenous ammonia from the blood in
order to stabilize pH. This process increases the risk of dehydration. Excess
dietary protein has also been shown to cause an excretion of calcium in the
urine. Both dehydration and loss of calcium are detrimental to athletic
Furthermore, too much protein upsets
macro-nutrient balance, displacing the intake of carbohydrates and fat and
causing the body to rely protein as a fuel. While protein can supply energy,
it wastes valuable resources and results in a number of undesirable effects.
Nitrogen balance is reflective of the dietary
intake of protein being balanced by the excretion of urea wastes. If nitrogen
excretion is greater than the nitrogen content (protein) of the diet, one is
said to be in negative nitrogen balance. This usually is indicated by the
breakdown of muscle tissue.
If the nitrogen excretion is less than the
content of the diet, a positive nitrogen balance is achieved and is indicated
by the formation of protein. The resulting tissue formation, as such, allows
repair and recovery from exercise.
Pre-workout protein recommendations
In general, a low-fiber, low-fat combination is
recommended as a pre-workout fuel source because it's digested more quickly
and thus reduces the risk of gastrointestinal distress. A small amount of
protein combined with carbohydrate is fine before a workout, but too much
protein isn't recommended.
Protein digestion is much slower than
carbohydrate, so a protein-only meal may not be fully digested, causing water
to be rapidly absorbed into the intestinal track. This increases the risk of
gastrointestinal distress during exercise, so it's important to avoid a large
protein meal several hours pre-exercise.
Protein for recovery
Research has shown that some protein consumed with
carbohydrates shortly before and after exercise does help the body recover
faster by initiating muscle repair and growth. Adding protein to a recovery
enhance the muscle's ability to store energy, but it
stimulate the muscles to rebuild. Relatively small amounts of protein are
required for muscle repair. Therefore, athletes should consume a combination
of carbohydrates and protein post-exercise.
Carbohydrates are used to refill the muscles
with fuel, while protein is used to help build and repair muscle tissue.
Within the scientific community, the optimal ratio of carbohydrates to protein
in the recovery process is still debated.
Based on experience and experimentation, most
endurance athletes find a ratio of 3:1 carbohydrate to protein works best.
This is a general recommendation, so athletes should be aware of their
individual differences; a little more or a little less might work optimally
for each individual.
Nutrient recovery guidelines
A generalized equation can be used to determine
recovery requirements. Most athletes need to consume .5 grams of carbohydrate
per pound of body weight every two hours for six to eight hours after a
workout. Therefore, if you're consuming 240 calories (60g) of carbohydrate
after a workout, with the generalized ratio of 3:1 (carbs to protein), 80
calories (20g) of protein should also be consumed.
Here's an example of the calculation for a
Multiply .5 grams of carbohydrate x 150 lbs.
= 75 grams of carbohydrate needed for recovery.
Multiply 75 grams x 4 (the number of calories in
a gram of carbohydrate) = 300 calories of carbohydrate.
If the recovery ratio of carbohydrate/protein is
3:1, then you need 100 calories of protein per 300 calories of carbohydrate.
(100 calories divided by 4 (4 calories per gram) = 25 grams of protein).
Athletes often rely on liquid mixes for
recovery. Carbohydrate-to-protein ratios are often formulated in the pre-made
mixes for optimal recovery. Creating individualized recovery drinks requires
experimentation with different types of carbohydrate and protein to determine
which combination works best for you.
If you prefer to refuel with solid food, here
are some healthy options:
- Half of a whole wheat bagel with 1/4 cup
cottage cheese or a tablespoon of peanut butter
- Yogurt smoothie, berries and a tablespoon
of protein powder
- Medium sweet potato and two egg whites
- Small turkey sandwich on whole wheat bread
- Bran cereal with skim milk and a few nuts
- Protein bars (many specially formulated
with optimal carbs and protein)
has a master's degree in dietetics with an emphasis in sports nutrition. She
enjoys working with athletes of all levels, and specializes in body
composition and weight management specific to individual needs. She
participates in many endurance and team events in order to relate personally
to her clientele. Ilana is The
head nutritionist, has worked with many local celebrities, and is the founder
of the nutrition program IndiFITualize. Listen to Ilana on the
show (Q100) as well as Dave FM
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