Adaptations to Aerobic Training

Question 1

What is cardiorespiratory endurance?

Answer 1

• Ability to sustain prolonged, dynamic exercise.
• Improvement through multisystem adaptations.

Question 2

What is endurance training

Answer 2

• Maximal endurance capacity= increased VO2 max
• increase sub-max endurance capacity:
  
  • lower HR at the same submaximal exercise intensity
  • More related to competitive endurance performance

Question 3

What are the 3 aspects of Muscular and what role do they play?

Answer 3

1. Fibre type
   - Increase the size and number of type 1 fibres
   - Type 2x may perform more like type 2a
   - Modest increase in the number of type 1 fibres
2. Capillary supply
   - increase the number of capillaries supplying each fibre
   - May be key factor in VO2 max
3. Myoglobin
   - an increase of myoglobin content by 75% to 80%
   - supporting increase of oxidative capacity in muscle

Question 4

What are the 2 types of Muscular function?

Answer 4

1. Mitochondrial function
   - increase the size and number
   - Magnitude of change dependent on training volume
2. Oxidative enzymes
   - increase activity with training
   - Continued increase even after VO2 max plateaus
   - Enhanced glycogen sparing

Question 5

What is lactate threshold under Metabolic?

Answer 5

• To a higher percentage of VO2 max
• Decrease of lactate production, increase in lactate clearance
• Allowing higher intensity without lactate accumulation
  Respiratory exchange ratio (RER)
• Decrease at both absolute and relative sub-max intensities
• Increase dependent on fat and decrease dependent on glucose

Question 6

What is the long term improvement in metabolic?

Answer 6

• Highest possible VO2 max is achieved after 12-18 months
• Performance continues to increase after VO2 max plateaus because lactate threshold continues to increase with training

Question 7

What are the factors dictating individual Responses?

Answer 7

1. Training status and pre-training VO2 max: - Relative improvement dependent on fitness
   - More sedentary individuals: greater increase
   - More fit individual: smaller increase
2. Heredity:
   - Finite VO2 max range determined by genetics (VO2 max altered within that range by training)
   - VO2 max is more similar for identical than fraternal twins, 25% - 50% of VO2 max variance due to heredity
3. Sex
   - Untrained female VO2 max < untrained male VO2 max
   - Trained female VO2 max closer to trained male VO2 max
   - Differences in older men vs older women
4. High vs low responders
   - Genetically determined variation in VO2 max for same training stimulants and compliance.
   - Physiological mechanisms
   - Reasons for tremendous variation in training outcomes for given training conditions.

Question 8

Adaptations to HIIT

Answer 8

• Stimulates mitochondrial biogenesis and changes in the capacity for carbohydrate and fat transport and oxidation
• Increase VO2 max and mitochondrial content
• Mitochondrial biogenesis depend largely on exercise intensity
• Potentially > with HIIT than MICT when work matched
• SIT= MICT despite the reduced volume
• VO2 max
  
  • HIIT > MICT when work matched

Question 9

Heart size

Answer 9

• With Aerobic training, increase heart mass and LV chamber size
• Increase plasma volume, increase LV volume, increase EDV, increase SV Volume loading effect
• Increased wall thickness, allowing a more forceful contraction of the left ventricle
• Increased internal dimensions due to an increase in ventricular filling (preload).

Question 10

Stroke volume

Answer 10

SV increase after training
- Resting, sub-max, max
- Plasma volume increase with training, increases EDV, increases preload
- Resting and sub-max HR and decrease with training, increase filling time, increase EDV
- Increase LV mass with training, increase force of contraction
- Alternated increase TPR with training, decrease in afterload.
- SV adaptations to training decrease with age

Question 11

Heart Rate

Answer 11

1. Resting HR
   - Decreases markedly
   - Increases parasympathetic, decreases sympathetic activity in the heat
2. Sub-max HR
   - decreases HR for the same given absolute intensity
   - More noticeable at higher sub-max intensities
3. Max HR
   - no significant change with training (decreases with age)

Question 12

Cardiac output

Answer 12

Little or no change at rest or during sub-max exercise with training
Maximal Q increases considerable due to increase of SV

Question 13

Cardiovascular

Answer 13

• Increase of blood flow to active muscle
• Increase capillarization, capillary recruitment
  - Increase capillary-to-fibre ratio
  - Increase total cross-sectional area for capillary exchange
• decrease blood flow to inactive regions
• Increase total blood volume
  Preventing decrease in venous return as a result of more blood in capillaries
  Blood volume: total volume increase rapidly
• increase blood plasma via increase plasma protein, increase water and NA+ retention
• Increase red blood cell volume
• Decrease plasma viscosity

Question 14

Respiratory

Answer 14

• Pulmonary ventilation
  - decrease at given sub-max intensity
  - increase at maximal intensity due to increasing tidal volume and respiratory frequency
• Pulmonary diffusion
  Unchanged during rest and at sub-max intensity
• increase at max intensity due to increase lung perfusion
• Arterial- venous O2 difference
  - Increase due to increase of O2 extraction active muscle blood flow
• Increase O2 extraction due to increase oxidative capacity