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Training Your
Energy Systems
By Robert Donatelli, PhD PT |
Tennis matches often take hours to
complete—particularly when a championship is on the line. In
order to play hard and perform at your best for several hours, you
need good energy sources and the ability to recycle that energy quickly,
which translate into training your energy systems.
Energy Sources
All three food nutrients—fats, proteins and carbohydrates—can
serve as fuel, although carbohydrates are the best. Chemical energy
produced from food is stored as adenosine triphosphate (ATP). ATP
then transfers energy for physical activities such as muscle contraction
during exercise. This process of energy transformations is called
metabolism.
Carbohydrates are the only food nutrient that can be used to create
energy without the presence or use of oxygen, known as anaerobic metabolism.
And exercise, especially explosive, short-duration movements, requires
the production of anaerobic energy.
Adenosine Triphosphate Energy System
Muscle stores relatively small amounts of ATP. After 2–3 seconds
of muscle contractions, ATP is replenished by the utilization of creatine
phosphate (CP) that is stored in the muscle. CP is stored in the muscle
in triple the quantity of ATP and can be used to instantaneously resynthesize
ATP.
To obtain CP, you can eat meats, fish or chicken, or you can use Creatine,
an ergogenic aid. Supplementation can increase muscle CP content by
about 20 percent, depending on how much CP is already stored in the
muscle prior to supplementation. To date there are no research studies
that have proven that the use of creatine, if used in moderation,
is harmful or dangerous to the body. Still, there is a saturation
point within the muscle for CO storage, and excess creatine is excreted
in the urine.
I offer the following precautions about creatine. Do not use creatine
supplementation if you have a preexisting kidney dysfunction or disease.
And do not use high-dose supplementation during periods of physical
activity under high thermal stress. Instead, ingest adequate fluids
and electrolytes when playing in hot weather. Pregnant and lactating
women as well as anyone under the age of 18 also should not take creatine
supplements.
Lactic Acid Energy System
Another system that provides immediate energy is the lactic acid system.
After 30 seconds of exercise the muscle produces lactic acid (LA).
If LA accumulates in your muscle, it can interfere with your muscle’s
ability to contract, which means your performance is hampered. Your
body needs to move LA from the muscle by means of the circulatory
system. Blood transports LA to the liver, where it is converted to
glycogen. During heavy exercise the heart muscle can utilize LA for
energy. Also, a small amount of LA is moved from the blood to the
skin, exiting the body as sweat. Some LA produced during high-intensity
exercise is retained in the muscle and in the post-exercise recovery
period it is reconverted to glycogen in the muscle cell. In addition,
some LA will remain as lactate circulating in the blood.
You can train both the ATP and LA energy systems to be more proficient
and tolerant. Here’s how to improve your energy systems that
are specific to explosive quick movements.
TRAINING ANAEROBIC ENERGY SYSTEM
At least one hour before training the anaerobic energy system, it
is important to eat carbohydrates, protein and a soluble fiber.
CP Energy System
Training the CP system involves exercise for 20–30 seconds of
duration, starting with five 20-second periods of exercise and working
up to ten. For example, perform 20 seconds of high-speed work on a
Stairmaster, rest for 55 seconds and start over. Continue this sequence
five times. After building up to 10 times of performing this sequence,
you can increase the workload by adding more resistance, such as a
weighted vest, and returning to five 20-second periods of exercise.
By performing this exercise regime, the body adapts to the training
by utilizing CP more efficiently. If the exercise periods are kept
under 30 seconds, LA is not produced.
Lactic Acid Energy System
The time period for training the lactic acid system is30 seconds to
3 minutes, with a rest period of 1 minute and 30 seconds between each
exercise session. A total of five exercise sessions should be performed,
increasing to ten within several weeks. Training should be performed
two to three times per week for eight weeks.
Once again the body becomes more proficient at clearing LA out of
the muscle and more tolerant to LA accumulation within the muscle
after eight weeks of training.
TRAINING AEROBIC ENERGY SYSTEM
Because tennis is an explosive sport with quick, short-duration movements,
training your anaerobic energy system is important. However, staying
on court for several hours does require aerobic fitness as well. After
five minutes of any activity, ATP replenishment is mainly accomplished
aerobically, which means in the presence or use of oxygen.
Aerobic fitness is accomplished through the frequency, duration and
intensity of aerobic exercise, such as running or bicycling. Running
three days per week, for six to eight weeks at a below-maximum heart
rate will improve your aerobic energy system’s efficiency.
All physical activity lasting more than five minutes require the use
of both anaerobic and aerobic energy systems. Therefore, in order
to perform to the best of your ability for several hours, training
both energy systems is critical. |
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