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CHAPTER 12
QUANTIFYING
SPORTS
TRAINING
AND
SPORTS
TRAINING
DOPING
Did You Know…?
A person’s rate of adaptation and response to training
depends on that individual. He or she cannot be forced
beyond his or her body’s capacity for development. Thus,
training programs must take these individual differences
into account.
Optimal Training Load
Progressive overload—progressive increase in training
load as body adapts
Training volume—duration or frequency
Training intensity—force of muscle action and stress on
the muscular and cardiovascular systems
w Resistance training (high intensity and low volume)
w Aerobic training (high volume and lower intensity)
Rest periods—without them, muscles
become chronically depleted
CHANGES IN HEART RATE AND
BLOOD LACTATE
Did You Know…?
Long daily workouts may not be the best training method
for some sports. It appears that training volume could be
reduced by as much as one half in some sports, without
reducing the training benefits and with less risk of
overloading.
Overtraining
w Training beyond the point that would be optimal; can be
related to intensity, duration, frequency, or any
combination of these three
w Staleness is a related concept
w The key is to design a training program that will provide
the optimal level of stress but will not overstress the
athlete
Symptoms of Overtraining Syndrome
w Decline in physical performance
w Decreased appetite and body weight loss
w Muscle tenderness
w Head colds, allergic reactions, or both
w Occasional nausea
w Sleep disturbances
w Elevated resting heart rate and blood pressure
w Feeling of “heaviness” and loss of desire to train and
compete
w Emotional instability
Possible Causes of Overtraining
w Periods of excessive training or emotional stress
w Abnormal responses in the autonomic nervous system—
sympathetic and parasympathetic
w Disturbances in endocrine function
w Depressed immune function
Sympathetic NS Overtraining
w Increased resting heart rate and blood pressure
w Loss of appetite and decreased body mass
w Sleep disturbances and emotional instability
w Elevated resting metabolic rate
Parasympathetic NS Overtraining
w Early onset of fatigue
w Decreased resting heart rate and blood pressure
w Rapid heart rate recovery after exercise
w Less common than sympathetic NS overtraining
TRAINING VOLUME AND RISK OF
INFECTION
Predicting Overtraining
w Increase in oxygen consumption for the same rate of work
(though impractical for coach to measure)
w Increased heart rate response to the same rate of work
w Declines in performance
.
VO2 IN EARLY AND LATE SEASON
HEART RATE RESPONSES TO TRAINING
Treatment of Overtraining
w Reduce training intensity for several days
w Rest completely for three to five days
w Seek counseling
w Prevent overtraining by alternating easy, moderate, and
hard training
w Eat sufficient carbohydrate to prevent glycogen depletion
Key Points
Training Demands
w Excessive training refers to training with an
unnecessarily high volume or intensity.
w Excessive training does not lead to
additional gains in performance and can
lead to overtraining.
w Increase the duration or frequency of
training to increase training volume.
(continued)
Key Points
Training Demands
w Training intensity can determine specific
adaptations to training.
w High-intensity, low-volume training
increases muscle strength and speed.
w High-volume,
low-intensity training (50% to
.
90% VO2max) increases aerobic capacity.
Key Points
Overtraining
w Overtraining leads to decreased
performance capacity.
w Symptoms of overtraining may occur
briefly with regular training.
w Overtraining may be caused by abnormal
responses in the autonomic nervous and
endocrine systems and suppressed
immune function.
w Heart rate response appears to be the
most reliable warning of overtraining.
w Overtraining syndrome is treated most
effectively with rest and proper nutrition.
Did You Know…?
Tapering for competition involves a reduction in training
intensity and volume. This rest allows your body to repair
itself and restore its energy reserves to prepare you for
your best performance.
Effects of Properly Tapering
w Muscular strength increases
w Energy reserves are restored
.
w No loss of VO2max occurs
w Performance increases (especially in swimmers)
Detraining
w Cessation of regular training; may be due to inactivity or
immobilization
w Loss of muscle size, strength, and power
w Decrease in muscular and cardiorespiratory endurance
w Loss of speed, agility, and flexibility
Loss of Muscle Strength
w Muscle atrophy accounts for a loss in development of
maximal muscle fiber tension.
w Normal fiber recruitment is disrupted; some fibers are
unable to be recruited.
w Muscle requires minimal stimulation (training once every
10 to 14 days) to retain training gains.
STRENGTH CHANGES WITH
DETRAINING
Loss of Endurance
w Decreased performance may be related to losses in
cardiorespiratory endurance.
w Oxidative enzyme activity in muscles decreases.
w Glycolytic enzymes remain unchanged with up to 84 days
of detraining.
w Muscle glycogen content (and thus storage capacity)
decreases.
w Acid-base balance becomes disturbed.
w Muscle capillary supply and fiber type may change.
.
DETRAINING, VO2MAX, AND OXIDATIVE
ENZYMES
DETRAINING AND MUSCLE GLYCOGEN
Loss of Cardiorespiratory Endurance
w Losses are greatest in highly trained individuals.
w Plasma volume decreases
w Stroke volume decreases
.
w VO2max decreases
w Endurance performance decreases
Did You Know…?
You can prevent rapid losses to your cardiorespiratory
endurance with a minimum of three training
sessions per
.
week at an intensity of at least 70% VO2max.
.
CHANGES IN VO2MAX WITH BED REST
Retraining
w Recovery of conditioning after a period of activity.
w Affected by fitness level and the length and extent of
inactivity.
w If a cast allows some range of movement, retraining time
can be reduced.
w Electrical stimulation of muscles can
prevent muscle fiber atrophy.
Key Points
Detraining and Retraining
w Detraining is the cessation of regular
physical training
w Retraining is resuming training after a
period of inactivity.
w The greater the training gains achieved,
the greater the losses with detraining.
w Detraining results in losses of muscle size,
strength, power, and endurance; speed,
agility, and flexibility; and cardiorespiratory
endurance.
w Detraining effects can be minimized by
training
three times a week at 70%
.
VO2max.
Examples in Sports
wFootball—anabolic steroids
w Cycling—blood doping or EPO; amphetamines
w Weight category athletes—diuretics, amphetamines
w Distance running—carbohydrate loading
Note: Scientific studies are limited by the accuracy of
measurements and individual day-to-day variability. Events
are won by hundredths of seconds or by centimeters.
Did You Know…?
The placebo effect refers to when your body’s
expectations of a substance determine your body’s
response to it. While the effect is psychological in origin,
the body’s physical response to the substance is real.
THE PLACEBO EFFECT
ON STRENGTH GAINS
Pharmacological Agents
w Alcohol
w Amphetamines
w Beta blockers
w Caffeine
w Cocaine
w Diuretics
w Marijuana
w Nicotine
Alcohol
w Provides energy (7 kcal/g) but inhibits metabolism
w Dulls pain sensation (increasing injury risk);
reduces anxiety
w Suppresses release of ADH which leads to dehydration
w Appears to impair psychomotor function
w Has no ergogenic effects on strength,
power, speed, or endurance
ALCOHOL SUPPRESSES ADH RELEASE
Amphetamines
w Increase mental alertness, blood pressure, heart rate,
blood glucose and FFA levels, and muscle tension
w Decrease sense of fatigue
w Redistribute blood flow to skeletal muscles
w May enhance speed, power, endurance, concentration,
and fine motor coordination
w May be addictive and can trigger cardiac
arrhythmia or death
Beta Blockers
w Prevent the binding of norepinephrine to its receptor, thus
decreasing sympathetic nervous system effects
w May improve accuracy (for shooting sports)
w Decrease aerobic capacity but have no effect on strength,
power, or muscular endurance
w Prolonged use can cause bradycardia, heart blockage,
hypotension, brochospasm, fatigue, and decreased
motivation
Caffeine
w Increases mental alertness, concentration, catecholamine
release, and mobilization and use of FFA by the muscles
w Decreases fatigue and lowers perception of effort
w Improves endurance performance; may improve sprint
and strength performance
w Can cause nervousness, insomnia, tremors,
diuresis, and lead to dehydration
Cocaine
w Blocks reuptake of norepinephrine and dopamine by
neurons
w Creates feelings of euphoria, alertness, and selfconfidence
w Masks fatigue and pain
w Has no evidence of ergogenic properties; likely ergolytic
w Extremely addictive; can cause psychological problems
and compromise heart function
Diuretics
w Increase urine production and excretion
w Used for weight reduction and to mask other drugs during
drug testing
w Cause weight loss (water loss)
w Can lead to dehydration, impaired thermoregulation, and
electrolyte imbalances
Marijuana
w Acts as a stimulant and depressant of CNS
w Impairs performance requiring hand-eye and motor
coordination, fast reaction times, tracking ability, and
perceptual accuracy
w Can lead to personality changes, memory impairment,
hallucinations, and psychotic-like behavior
w May pose same risks as cigarette smoking (if smoked)
Nicotine
w Increases alertness and may calm nervousness
.
w Lowers VO2max values (when smoked) and peripheral
circulation
w Increases heart rate, blood pressure, autonomic reactivity,
vasoconstriction, ADH and catecholamine secretion, blood
lipid levels, plasma glucose, glucagon, insulin, and cortisol
w Is addictive and causes various cancers
and cardiovascular diseases
Hormonal Agents
w Anabolic steroids
w Human growth hormone
w Oral contraceptives
Anabolic Steroids
w Are nearly identical to male sex hormones; synthetic form
maximizes building effects
w Increase muscle mass and strength
w Can cause testicular atrophy, reduced sperm count, and
prostate and breast enlargement in men
w Can cause breast regression, masculinization, and
menstrual disruption in women
w Cause personality changes, liver damage, and
cardiovascular disease
BODY CHANGES WITH ANABOLIC
STEROIDS
Human Growth Hormone
w Secreted naturally by pituitary; synthetic form used by
some athletes
w Difficult to detect synthetic from natural in drug testing
w Proven to increase lipolysis and blood glucose levels;
changes in muscle mass and strength are found in some
studies, but not in the best controlled studies or studies
with athletes
w Can cause acromegaly, enlargement of
internal organs, muscle and joint weakness,
diabetes, hypertension, and heart disease
Oral Contraceptives
w Control menstrual cycle
w Little research on ergogenic properties
w May alleviate symptoms of PMS and restore menstrual
cycle
w Can cause nausea, weight gain, fatigue, hypertension,
liver tumors, blood clots, stroke, or heart attack.
Physiological Agents
w Blood doping
w Erythropoietin
w Oxygen supplementation
w Aspartic acid
w Bicarbonate loading
w Phosphate loading
Blood Doping
w Artificial increase in total volume of red blood cells (via
transfusion or EPO)
w Improves endurance performance by increasing blood’s
O2-carrying capacity
.
w Increases VO2max, time to exhaustion, and measurable
performance
w Can cause blood clotting, heart failure, and transfusion
complications
.
VO2MAX AND FATIGUE AFTER BLOOD
DOPING
PERFORMANCE IMPROVEMENT AFTER
BLOOD DOPING
Erythropoietin
w Natural hormone produced by the kidneys to stimulate red
blood cell production
w Can be cloned and administered to increase red blood cell
volume
.
w Increases VO2max and time to exhaustion
w Can cause blood clotting and heart failure due to
increased blood viscosity
Oxygen Supplementation
w Breathed by athlete to increase oxygen content of blood
w Can improve performance if administered during exercise,
but not before or after
w Too cumbersome to be practical
w No serious risks known
OXYGEN SUPPLEMENTATION AND
PERFORMANCE
Aspartic Acid
w An amino acid involved in liver’s conversion of ammonia
to urea
w Thought to reduce ammonia buildup during exercise and
thus offset fatigue
w Insufficient and conflicting research of ergogenic
properties
w No serious risks known
Bicarbonate
w Naturally part of body’s buffering system to maintain
normal pH
w Loading increases blood alkalinity so that more lactate
can be cleared (delay fatigue)
w Ingesting 300 mg per kg body weight can increase
performance in all-out exercise bouts between 1 and 7
minutes
w Can cause gastrointestinal cramping, bloating, and
diarrhea
BICARBONATE AND BLOOD
CONCENTRATIONS
Phosphate
Loading is thought to increase phosphate levels throughout
body, which then
w Increase potential for oxidative phosphorylation and PCr
synthesis
w Enhance oxygen release to the cells
w Improve cardiovascular response to exercise and
buffering and endurance capacities
Studies are divided on results of phosphate loading.
No risks are yet known.
Nutritional Agents
w Amino acids
w L-carnitine
w Creatine
w Chromium
w Glycerol
Amino Acids
w L-tryptophan and BCAA
w Proposed to increase endurance performance by delaying
fatigue
w Studies are inconclusive on effects on performance
Creatine
w Supplement to better maintain muscle ATP levels
w Shown to increase strength and possibly fat-free body
mass
w Not shown to help endurance performance, sprint running,
or sprint swimming performance
Chromium
w Essential trace mineral in foods that helps metabolize
carbohydrate, fat, and protein
w Often deficient in diets and lost via exercise
w Supplements thought to increase glycogen synthesis and
amino acid incorporation in muscle and improve glucose
tolerance
w Studies show little or no benefit