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Section 06:
Exercise Training to Improve Performance
Chapter 21 – Training for Anaerobic and Aerobic Power
Chapter 22 – Muscular Strength: Training Muscles to Become Stronger
Chapter 23 – Special Aids to Exercise Training and Performance
HPHE 6710 Exercise Physiology II
Dr. Cheatham
Chapter 21
Training for Anaerobic and Aerobic Power
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Chapter Objectives
• Understand the concepts of overload, specificity, reversibility
• Understand the metabolic adaptations associated with anaerobic training
• Understand the metabolic adaptations associated with aerobic training
• Understand the cardiovascular and pulmonary adaptations to aerobic training
Training Principles
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Training Principles
• Overload Principle
– Regular application of a specific exercise overload enhances physiologic function to induce a training response
• Overload may be achieved using a combination of:
– Intensity
– Duration
– Frequency
Training Principles
• Specificity Principle
– Adaptations in metabolic and physiologic functions that depend upon the type and mode of overload imposed.
– Specific exercise elicits specific adaptations to create specific training effects
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Training Principles
• Specificity Principle (cont’d)
– Specificity of VO2max
Training Principles
• Specificity Principle (cont’d)
– Specificity of local changes
• Overloading specific muscle groups with endurance training enhances exercise performance and aerobic power by facilitating oxygen transport AND use at the local level of the trained muscle
• Example:
– Vastus lateralis muscle of well‐trained cyclists has greater oxidative capacity than that of endurance runners
» Greater regional blood flow in active tissues
• Increases microcirculation
• More effective distribution of Q
• Combined effects of both factors
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Training Principles
Training Principles
• Specificity Principle (cont’d)
– Individual differences principle
• Many factors contribute to individual variation in the training response
– A person’s relative fitness values at the start of training (i.e. initial value)
– Genetic factors
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Training Principles
Training Principles
• Reversibility Principle
– Loss of physiologic and performance training adaptations occurs rapidly when a person terminates participation in regular exercise
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Training Principles
Training Principles
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Physiologic Consequences of Training
Quick Metabolism Review
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Quick Metabolism Review
Quick Metabolism Review
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Anaerobic System Changes with Training
• Increases in resting muscle levels of
– ATP
– PCr
– Free creatine
– Glycogen
– Glycolytic enzymes
• Resulting in increased capacity to generate blood lactate
Anaerobic System Changes with Training
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Anaerobic System Changes with Training
Aerobic System Changes with Training
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Aerobic System Changes with Training
• Metabolic Adaptations
– Metabolic Machinery
• Number and size of mitochondria
• Aerobic system enzymes
– Nearly two‐fold increase within 5 to 10 days
• Increased mitochondrial capacity to generate ATP aerobically
Aerobic System Changes with Training
• Metabolic Machinery
– Number and size of mitochondria
• Example:
– Exercise at the LT for 30 min/day, 5 days/week, 6 weeks increased mitochondrial density by 40%.
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Aerobic System Changes with Training
Number and Size of Mitochondria
Aerobic System Changes with Training
• Metabolic Machinery (cont’d)
– Aerobic system enzymes
• Nearly two‐fold increase within 5 to 10 days
94% 
117% 
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Aerobic System Changes with Training
Aerobic System Enzymes
Aerobic System Changes with Training
• Capillary Density
– Increase perfusion of active muscle with blood
– Greater delivery of O2 and points for diffusion
– Aerobic training increases the number of overall capillaries and the capillary‐to‐fiber ratio
7% higher # of capillaries
38% higher c‐to‐f ratio
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Aerobic System Changes with Training
Capillary Density
29% 
26% 
Aerobic System Changes with Training
Capillary Density
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Aerobic System Changes with Training
Capillary Density
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Aerobic System Changes with Training
• Metabolic Adaptations (cont’d)
– Fat Metabolism
• Endurance training increases the oxidation of fatty acids for energy during submaximal exercise
• Increases in training‐induced lipolysis occur due to:
–
–
–
–
Greater blood flow within trained muscle
More fat‐mobilizing and fat‐metabolizing enzymes
Enhances muscle mitochondrial respiratory capacity
Decreases catecholamine release for the same absolute power output
• Why is an increase in fat metabolism beneficial for endurance performance?
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Aerobic System Changes with Training
Aerobic System Changes with Training
Fat Metabolism
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Aerobic System Changes with Training
Aerobic System Changes with Training
• Metabolic Adaptations (cont’d)
– Carbohydrate Metabolism
• Trained muscle exhibits enhanced capacity to oxidize carbohydrate during maximal exercise
• Muscle Fiber Type and Size
– Aerobic training elicits metabolic adaptations in each type of muscle fiber
– “Basic” fiber type probably doesn’t change much
– Selective hypertrophy occurs in the different muscle fiber types with specific overload training
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Aerobic System Changes with Training
Aerobic System Changes with Training
• Metabolic Adaptations (cont’d)
– Myoglobin
• Slow twitch fibers contain relatively large quantities of myoglobin
• In animals, amount of myoglobin relates to their physical activity
• Unclear in humans whether regular exercise exerts any meaningful effect on myoglobin levels
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Aerobic System Changes with Training
• Cardiovascular Adaptations
Aerobic System Changes with Training
• Cardiovascular Adaptation (cont’d)
– Cardiac Hypertrophy: The “Athlete’s Heart”
• Long‐term aerobic training generally increases the heart’s mass and volume with greater left‐ventricular end‐
diastolic volumes noted during rest and exercise.
– Eccentric hypertrophy: Size of the left ventricular cavity
– Concentric hypertrophy: Modest thickening of the walls
• Increases sensitivity to calcium
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Aerobic System Changes with Training
Aerobic System Changes with Training
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Aerobic System Changes with Training
• Cardiovascular Adaptations (cont’d)
– Plasma Volume
• A 12 to 20% increase in PV occurs after 3 to 6 aerobic training sessions
– Measurable change within 24 hours
• Increases synthesis and retention of albumin
• Hemoglobin mass and blood volume averaged 35% higher in endurance athletes compared to untrained subjects.
Aerobic System Changes with Training
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Aerobic System Changes with Training
Role of albumin in controlling plasma volume
Interstitial Space
Blood
Vessel
Aerobic System Changes with Training
CON
EX
EXSAL
30 min
REC
150 min
REC
 0.4%
 12.3%
 13.3%
24 hrs
REC
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Aerobic System Changes with Training
30 min
REC
150 min
REC
24 hrs
REC
Aerobic System Changes with Training
• Cardiovascular Adaptations (cont’d)
– Heart Rate
• Resting and submaximal
exercise HR’s are decreased
– Increased vagal tone
– Decrease in intrinsic firing rate of SA node
– Relationship with SV
» “Chicken or the egg”
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Aerobic System Changes with Training
• Cardiovascular Adaptations (cont’d)
– Stroke Volume
• Increased at rest, submaximal exercise, and maximal exercise
– Increased left‐
ventricular volume
» PV and mass
– Reduced cardiac and arterial stiffness
– Increased diastolic filling time
– Improved cardiac contractility
Aerobic System Changes with Training
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Aerobic System Changes with Training
• Cardiovascular Adaptations (cont’d)
– Cardiac Output
• Most significant adaptation
• Maximal cardiac output increases with endurance training
• Submaximal cardiac output may be the same or slightly decreased at a given submaximal
exercise intensity
– If it is lower, what does that mean (i.e. what other variable must be higher?)
Aerobic System Changes with Training
• Cardiovascular Adaptations (cont’d)
– Oxygen Extraction (a‐vO2 diff)
• Increases the quantity of oxygen extracted from circulating blood.
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Aerobic System Changes with Training
• Cardiovascular Adaptations (cont’d)
– Blood Flow Distribution
• Submaximal Exercise
– Lower Q but greater and unchanged or slightly lower muscle blood flow
– Increase in blood flow to muscles with high percentage of Type I fibers at the expense of blood flow to muscles with high percentage of Type II fibers
» Rapid training‐induced changes in the vasoactive properties of large arteries and local resistance vessels
» Changes that enhance oxidative capacity
Aerobic System Changes with Training
• Cardiovascular Adaptations (cont’d)
– Blood Flow Distribution (cont’d)
• Maximal Exercise
– Increase in total blood flow with training
» Larger maximal Q
» Greater reductions in blood flow to non‐active areas
» Enlargement of vascular cross‐sectional area
– Myocardial Blood Flow
• Increases
– Blood Pressure
• Decreases
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Aerobic System Changes with Training
Aerobic System Changes with Training
• Pulmonary Adaptations with Training
– Maximal exercise
• Increases ventilation (tidal volume and frequency)
– Submaximal exercise
• Reduces the ventilatory equivalent for oxygen
• Tidal volume increases and breathing frequency decreases
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Aerobic System Changes with Training
Aerobic System Changes with Training
• Pulmonary Adaptations (cont’d)
– Training may benefit ventilatory endurance
• Reduces overall exercise energy demands because of less respiratory work
• Reduces lactate production by ventilatory muscles
• Enhances how ventilatory muscles metabolize circulating lactate as metabolic fuel
– Explain this…
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Aerobic System Changes with Training
• Blood Lactate Concentration
Aerobic System Changes with Training
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