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Have you ever started a long run or ride feeling amazing only to suffer tremendously towards the end of the workout? Perhaps your muscles felt like they were experiencing a migraine headache. And every slight incline
in the road felt like you were climbing Mount Everest. Even those typical
downhill blessings felt horrible, almost as if someone were hammering your legs
into the ground or stabbing your muscles with a blade. Most endurance
athletes have had at least one or two less-than-desirable long training days
throughout an endurance-training program, whether it is for marathons,
triathlons, or adventure racing. Fortunately, these “bad” days can be
minimized through careful planning of dietary and fluid needs during longer
training bouts.
In training bouts lasting longer than 60-90 minutes, there is profound evidence
that supplementation with carbohydrates will help enhance endurance
performance. Furthermore, it is well established that fluids, especially
those containing electrolytes, play a critical role in maintaining proper
muscle function, including energy production and muscle contraction. More
recently, research has pointed towards the potential benefits of
supplementation with both carbohydrate and protein during prolonged training
bouts. More breakthrough sports nutrition research suggests that
supplementation with the following nutrients during exercise may help keep you
running strong for the long haul: antioxidants, arginine, branched chain
amino acids, glutamine, Siberian Ginseng. Below, I offer 5 nutritional
strategies that will help ward off aggravating aches and pains that can inhibit
endurance performance.
#5: LOAD YOUR FUEL TANK
BEFORE STARTING
While you can get away with not eating before training bouts lasting less than
an hour, performance tends to decline if food is neglected prior to exercise
lasting longer than an hour. The food consumed prior to longer training
days help to stabilize energy levels during the initial stages of exercise and
also help to increase the efficiency of fat burning. As a general rule, for
every hour prior to exercise, consume about 2 calories per pound of lean body
weight, aiming at 1 gram of protein for every 4 grams of carbohydrate.
The majority of carbohydrates ingested beyond 1 hour prior to the start of the
workout should have a low-to-moderate glycemic index (refer to
http://www.glycemicindex.com/ for glycemic lists). Because
my long training days start early in the morning, I generally consume an energy
bar with 16 ounces of fluid about an hour prior to training. Note that
each athlete is unique in how long it takes to digest the food eaten; it is
recommended to allow at least 1-4 hours. High glycemic carbohydrates,
which include most sport drinks, are appropriate for consumption within an hour
prior to starting, but should not make up the majority of a meal eaten more
than 1 hour prior to starting a workout.
#4: AN HOUR TO 90 MINUTES
INTO TRAINING, START REFUELING YOUR TANK
Athletes who fail to refuel their tank during long training bouts may experience
“the wall” and “bonking.” The average athlete who follows a
carbohydrate-rich diet stores approximately 1,900 calories of carbohydrates
(AKA glycogen) in their muscles and liver. The goal on longer training
days is to preserve this glycogen and use the ever-so-abundant amount of fat
stores we have in our body, which is equivalent to about 100,000
calories. After about an hour of exercise, our liver glycogen stores run
low, causing breakdown of muscle glycogen until the point of depletion.
Once muscle glycogen stores become depleted, the body dips into protein
reserves, causing muscles to cramp and become vulnerable to injury. This
very unpleasant phenomenon is known as “the wall” and generally occurs between
mile 18 and mile 20 in a marathon or during run transition of a long-course
triathlon. In order to correct this glycogen depletion in the muscles,
the liver will start regenerating glucose from amino acids to be sent down to
the depleted muscles. Unfortunately, this causes a shortage of glucose
travelling to the brain, leading to dizziness, confusion, and lightheadedness
(AKA “bonking”). Furthermore, it will severely compromise your ability to
recover from the race/training bout.
In order to prevent “the wall” and “bonking” and increase our fat burning
capabilities, it is essential to start refueling our tank after about an hour
exercise. Remember that fats burn in a carbohydrate flame; without an adequate
carbohydrate supply, fat is no longer burned and protein becomes the fuel of
choice. Groundbreaking research over at the University of Texas at Austin
has discovered that athletes who supplement with both high glycemic
carbohydrates and protein in a 4:1 ratio may enhance endurance capability by as
much as 24% when compared to athletes who supplement with only carbohydrates or
water. The following equations can be used to determine your hourly
calorie needs following the first 60-90 minutes of exercise:
2 calories x lean body weight in pounds
Carbohydrates should be the focus when training lasts under 2 hours.
Beyond 2 hours of training, aim at consuming 1 gram of protein for every 4-7
grams of carbohydrate to help protect against premature muscle fatigue. Accelerade,
a powder formula that contains a 4:1 ratio of carbohydrates and protein, was
the product used in the research conducted by Dr. John Ivy over at University
of Texas at Austin and can be purchased at most sports/running specialty
stores. You can create your own 4-7:1 ratio by adding a teaspoon to a
full tablespoon of whey or soy protein per 25 grams of carbohydrate. If a
kitchen experiment sounds too complicated, customized nutrition formulas can be
created by a sports nutrition company called InfinIT (www.infinitnutrition.com).
If you decide a customized formula is of interest to you and would like help
creating it, please free to contact me and I’ll give you some guidance on how
to create your personal formulation.
#3: DRINK UP!
The human body can last a lot longer without food than it can without
water. In fact, dehydration (AKA loss of fluids) can have a profound
effect on endurance performance. Athletes who wait until they are thirsty
to start drinking during training will see about a 15% decline in their
performance capability. Besides thirst, symptoms of dehydration include
muscle cramping, muscle fatigue, nausea, vomiting, diarrhea, and chills.
In the most severe cases of dehydration, the body’s core temperature may
increase to 108oF, which, if prolonged, will lead to kidney failure
and death.
In order to prevent dehydration, the American College of Sports Medicine (ACSM)
recommends that athletes fortify themselves with about 16 ounces of fluids
about an hour before exercise. In addition, in 15-20 minute increments,
about 5-12 ounces of fluids should be consumed. To personalize your fluid
regimen during exercise, determine your sweat rate by weighing yourself pre-
and post-exercise. Make sure to measure your fluid intake during
exercise. Every pound of body weight lost during training indicates a
loss of 16 ounces of fluid and a consequent need to increase fluid intake by
that amount. For example, if you lose 16 ounces of fluid on a 30-minute
run in which you haven’t supplemented with fluids, your fluid needs can be
estimated at 32 ounces per hour. Note that sweat rate increases on days
where the temperature and humidity are high. A product called glycerol
(such as Pro-Hydrator) may help reduce dehydration and fatigue during exercise
by prompting the body to store more water than possible by drinking plain water
alone; beware that a lot athletes tend to experience severe GI distress with
glycerol so the product may not be feasible for use during training.
#2: DON’T FORGET
ELECTROLYTES!
Note that sweat consists of more than just plain water; it also contains
dissolved salts or “electrolytes” that give sweat its salty taste.
Electrolytes, which include sodium, chloride, potassium, magnesium, and
calcium, are vital to cellular activity and also play a significant role in the
contraction and relaxation of muscles and nerve-impulse transmission. An
electrolyte imbalance, therefore, can lead to severe cramping, muscular
fatigue, and even death..
In training bouts lasting longer than an hour, the amount of electrolytes lost
via sweat becomes significant, thereby making replacement of these electrolytes
essential for maximum performance. Low blood sodium or hyponatremia is
the most common electrolyte imbalance in endurance athletes. Continuous
loss of sodium via sweat without replacement during exercise causes blood
levels of sodium to drop, leading to inefficient muscle contraction and nerve
transmission and, in severe cases, seizures and/or cardiac arrest. In
order to prevent symptoms associated with an electrolyte imbalance, consume 4-8
ounces of a sports drink every 15 minutes. The sports drink should
contain the following approximate concentration of electrolytes per 8-12 ounces
of fluid: Sodium 150-250 mg, Chloride 45-75 mg, Potassium 50-80 mg,
Magnesium 20-30 mg, Calcium, 10-15 mg.
#1: THE FOLLOWING
SUPPLEMENTS MAY HELP:
Note that research on nutritional supplements are preliminary; more research
needs to be conducted to make absolute claims and recommendations for
supplementation. Take precaution with all supplements; do not exceed
recommended doses and check with your pharmacist about potential
drug-nutrient interactions.
Antioxidants: Vitamins C and E, especially when taken
synergistically, have been proven to reduce the oxidative stress and consequent
muscle damage that occurs during intensive exercise. The performance
daily intake (PDI) of vitamin C for athletes is 800 to 3,000 mg while the PDI
for vitamin E for men and women athletes is 200 to 1,000 IU.
B-Vitamins : B-vitamins play a critical role
with breakdown and conversion of our macronutrients (carbohydrates, fats,
proteins) into energy for use during training. Because B-vitamins are
water soluble, we do lose small amounts in sweat which may affect metabolism
and energy production during exercise. Therefore, replacement of our
B-vitamins should help keep our metabolic process running at peak during
exercise.
Arginine. Arginine, which can be found in the product
Accelerade, is a non-essential amino acid that seems to increase the
availability of glucose during exercise when taken synergistically with
carbohydrate. Recommended dosage during exercise is approximately 0.04
grams per pound of body weight each hour.
Branch Chained Amino Acids: Branched chain amino
acids, which include leucine, isoleucine, and valine, may help reduce mental
fatigue during exercise by regulating the entry of tryptophan into the
brain. One study of 193 marathoners showed an improvement in overall
performance, primarily in the slower runners.
In order to feel your best during long training bouts and maximize endurance
performance, it is not only important to follow the nutritional strategies
shared in this article, but it is also important to monitor your energy levels
and taper back your training a few days prior to long training. Happy
endurance training!!!
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