1. Adaptations to Aerobic and Anaerobic Training
Chapter 11
Adaptations to Aerobic and Anaerobic Training

2. Adaptations to Aerobic Training: Cardiorespiratory Endurance
Ability to sustain prolonged, dynamic exercise
Improvements achieved through multisystem adaptations (cardiovascular, respiratory, muscle, metabolic)
Endurance training
–  Maximal endurance capacity =  VO2max
–  Submaximal endurance capacity
Lower HR at same submaximal exercise intensity
More related to competitive endurance performance

3. Figure 11.1

4. Adaptations to Aerobic Training: Major Cardiovascular Changes
Heart size
Stroke volume
Heart rate
Cardiac output
Blood flow
Blood pressure
Blood volume

5. Adaptations to Aerobic Training: Cardiovascular
O2 transport system and Fick equation
VO2 = SV x HR x (a-v)O2 difference
–  VO2max =  max SV x max HR x  max (a-v)O2 difference
Heart size
With training, heart mass and LV volume 
– Target pulse rate (TPR)  cardiac hypertrophy   SV
–  Plasma volume   LV volume   EDV   SV
Volume loading effect

6. Adaptations to Aerobic Training: Cardiovascular
SV  after training
Resting, submaximal, and maximal
Plasma volume  with training   EDV   preload
Resting and submaximal HR  with training   filling time   EDV
–  LV mass with training   force of contraction
Attenuated  TPR with training   afterload
SV adaptations to training  with age

7. Figure 11.3

8. Table 11.1

9. Adaptations to Aerobic Training: Cardiovascular
Resting HR
–  Markedly (~1 beat/min per week of training)
–  Parasympathetic,  sympathetic activity in heart
Submaximal HR
–  HR for same given absolute intensity
More noticeable at higher submaximal intensities
Maximal HR
No significant change with training
–  With age

10. Figure 11.4

11. Adaptations to Aerobic Training: Cardiovascular
HR-SV interactions
Does  HR   SV? Does  SV   HR?
HR, SV interact to optimize cardiac output
HR recovery
Faster recovery with training
Indirect index of cardiorespiratory fitness
Cardiac output (Q)
Training creates little to no change at rest, submaximal exercise
Maximal Q  considerably (due to  SV)

12. Figure 11.5

13. Figure 11.6

14. Adaptations to Aerobic Training: Cardiovascular
•  Blood flow to active muscle
•  Capillarization, capillary recruitment
–  Capillary:fiber ratio
–  Total cross-sectional area for capillary exchange
•  Blood flow to inactive regions
•  Total blood volume
Prevents any decrease in venous return as a result of more blood in capillaries

15. Adaptations to Aerobic Training: Cardiovascular
Blood pressure
–  BP at given submaximal intensity
–  Systolic BP,  diastolic BP at maximal intensity
Blood volume: total volume  rapidly
–  Plasma volume via  plasma proteins,  water and Na+ retention (all in first 2 weeks)
–  Red blood cell volume (though hematocrit may )
–  Plasma viscosity

16. Cardiovascular Adaptations to Chronic Endurance Exercise

17. Adaptations to Aerobic Training: Respiratory
Pulmonary ventilation
–  At given submaximal intensity
–  At maximal intensity due to  tidal volume and respiratory frequency
Pulmonary diffusion
Unchanged during rest and at submaximal intensity
–  At maximal intensity due to  lung perfusion
Arterial-venous O2 difference
–  Due to  O2 extraction and active muscle blood flow
–  O2 extraction due to  oxidative capacity

18. Adaptations to Aerobic Training: Muscle
Fiber type
–  Size and number of type I fibers (type II  type I)
Type IIx may perform more like type IIa
Capillary supply
–  Number of capillaries supplying each fiber
May be key factor in  VO2max
Myoglobin
–  Myoglobin content by 75 to 80%
Supports  oxidative capacity in muscle

19. Adaptations to Aerobic Training: Muscle
Mitochondrial function
–  Size and number
Magnitude of change depends on training volume
Oxidative enzymes (SDH, citrate synthase)
–  Activity with training
Continue to increase even after VO2max plateaus
Enhanced glycogen sparing

20. Adaptations to Aerobic Training: Muscle
High-intensity interval training (HIT): time-efficient way to induce many adaptations normally associated with endurance training
Mitochondrial enzyme cytochrome oxidase (COX)  same after HIT versus traditional moderate-intensity endurance training

21. Adaptations to Aerobic Training: Metabolic
Lactate threshold
–  To higher percent of VO2max
–  Lactate production,  lactate clearance
Allows higher intensity without lactate accumulation
Respiratory exchange ratio (RER)
–  At both absolute and relative submaximal intensities
–  Dependent on fat,  dependent on glucose

22. Figure 11.10

23. Adaptations to Aerobic Training: Metabolic
Resting and submaximal VO2
Resting VO2 unchanged with training
Submaximal VO2 unchanged or  slightly with training
Maximal VO2 (VO2max)
Best indicator of cardiorespiratory fitness
–  Substantially with training (15-20%)
–  Due to  cardiac output and capillary density

24. Table 11.3

25. Table 11.3 (continued)

26. Adaptations to Aerobic Training: Metabolic
Long-term improvement
Highest possible VO2max achieved after 12 to 18 months
Performance continues to  after VO2max plateaus because lactate threshold continues to  with training
Individual responses dictated by
Training status and pretraining VO2max
Heredity

27. Adaptations to Aerobic Training: Metabolic
Training status and pretraining VO2max
Relative improvement depends on fitness
The more sedentary the individual, the greater the 
The more fit the individual, the smaller the 
Heredity
Finite VO2max range determined by genetics, training alters VO2max within that range
Identical twin’s VO2max more similar than fraternal’s
Accounts for 25 to 50% of variance in VO2max

28. Adaptations to Aerobic Training: Metabolic
Sex
Untrained female VO2max < untrained male VO2max
Trained female VO2max closer to male VO2max
High versus low responders
Genetically determined variation in VO2max for same training stimulus and compliance
Accounts for tremendous variation in training outcomes for given training conditions

29. Adaptations to Aerobic Training: Fatigue Across Sports
Endurance training critical for endurance-based events
Endurance training important for non-endurance-based sports, too
All athletes benefit from maximizing cardiorespiratory endurance

30. Adaptations to Anaerobic Training
Changes in anaerobic power and capacity
Wingate anaerobic test closest to gold standard for anaerobic power test
Anaerobic power and capacity  with training
Adaptations in muscle
–  In type IIa, IIx cross-sectional area
–  In type I cross-sectional area (lesser extent)
–  Percent of type I fibers,  percent of type II

31. Adaptations to Anaerobic Training
ATP-PCr system
Little enzymatic change with training
ATP-PCr system-specific training  strength 
Glycolytic system
–  In key glycolytic enzyme activity with training (phosphorylase, PFK, LDH, hexokinase)
However, performance gains from  in strength

32. Specificity of Training and Cross-Training
VO2max substantially higher in athlete’s sport-specific activity
Likely due to individual muscle group adaptations
Cross-training
Training different fitness components at once or training for more than one sport at once
Strength benefits blunted by endurance training
Endurance benefits not blunted by strength training