1. chapter 10
Adaptations to Aerobic and Anaerobic Training

2. Learning Objectives
Learn how cardiorespiratory endurance differs from muscular endurance
Learn about the cardiorespiratory adaptations to endurance training
Find out what changes occur in the oxygen transport system as a result of endurance training
(continued)

3. Learning Objectives (continued)
Examine metabolic adaptations that occur with endurance training
Learn how cardiorespiratory and metabolic adaptations benefit performance in both endurance and nonendurance sports
(continued)

4. Learning Objectives (continued)
Find out how training can maximize our energy systems and our potential to perform
Learn the differing adaptations that occur with aerobic and anaerobic training
Find out how specific types of aerobic and anaerobic training can improve performance

5. Aerobic and Anaerobic Training
Aerobic (endurance) training
Improved central and peripheral blood flow
Enhances the capacity of muscle fibers to generate ATP
Anaerobic training
Increased short-term, high-intensity endurance capacity
Increased anaerobic metabolic function
Increased tolerance for acid–base imbalances during highly intense effort

6. Endurance
Muscular endurance: the ability of a single muscle or muscle group to sustain high-intensity repetitive or static exercise
Cardiorespiratory endurance: the entire body’s ability to sustain prolonged, dynamic exercise using large muscle groups

7. Evaluating Cardiorespiratory Endurance.
VO2max
Highest rate of oxygen consumption attainable during maximal exercise
VO2max can be increased by 10-15% with 20 weeks of endurance training .

8. Increases in VO2max With Endurance Training.
Increases in VO2max With Endurance Training
Fick equation:
VO2 = SV  HR  (a-v)O2 diff .

9. Changes in VO2max With 12 Months of Endurance Training.
Changes in VO2max With 12 Months of Endurance Training

10. Cardiovascular Adaptation to Training
Heart size
Stroke volume
Heart rate
Cardiac output
Blood flow
Blood pressure
Blood volume

11. Percentage Differences in Heart Size Among Three Groups of Athletes Compared With Untrained Group

12. Heart Size (Central) Adaptation to Endurance Training
Key Points
The left ventricle changes significantly in response to endurance training
The internal dimensions of the left ventricle increase as an adaptation to an increase in ventricular filling secondary to an increase in plasma volume and diastolic filling time
Left ventricular wall thickness and mass increase, allowing for greater contractility

13. Measuring Heart Size: Echocardiography
© Tom Roberts

14. Changes in Stroke Volume With Endurance Training

16. Stroke Volume Adaptations to Endurance Training
Key Points
Endurance training increases SV at rest and during submaximal and maximal exercise
Increases in end-diastolic volume, caused by an increase in blood plasma and greater diastolic filling time (lower heart rate), contribute to increased SV
Increased ventricular filling (preload) leads to greater contractility (Frank-Starling mechanism)
Reduced systemic vascular resistance (afterload)

17. Heart Rate Adaptations to Endurance Training
Resting
Decreases by ~1 beat/min with each week of training
Increased parasympathetic (vagal) tone
Submaximal
Decreases heart rate for a given absolute exercise intensity
Maximal
Unchanged or decreases slightly

18. Changes in Heart Rate With Endurance Training

19. Heart Rate Recovery
The time it takes the heart to return to its resting rate after exercise
Faster rate of recovery after training
Indirect index of cardiorespiratory fitness
Prolonged by certain environments (heat, altitude)
Can be used as a tool to track the progress of endurance training

20. Changes in Heart Rate Recovery With Endurance Training

21. Cardiac Output Adaptations to Endurance Training.
Q = HR x SV
Does not change at rest or during submaximal exercise (may decrease slightly)
Maximal cardiac output increases due largely to an increase in stroke volume

22. Changes in Cardiac Output With Endurance Training

23. Cardiac Output Adaptations
Key Points
Q does not change at rest or during submaximal exercise after training (may decrease slightly)
Q increases at maximal exercise and is largely responsible for the increase in VO2max
Increased maximal Q results from the increase in maximal SV . . . .

24. Blood Flow Adaptations to Endurance Training
Blood flow to exercising muscle is increased with endurance training due to:
Increased capillarization of trained muscles
Greater recruitment of existing capillaries in trained muscles
More effective blood flow redistribution from inactive regions
Increased blood volume
Increased Q .

26. Blood Pressure (BP) Adaptations to Endurance Training
Resting BP decreases in borderline and hypertensive individuals (6-7 mmHg reduction)
Mean arterial pressure is reduced at a given submaximal exercise intensity (↓ SBP, ↓ DBP)
At maximal exercise (↑ SBP, ↓ DBP)

27. Blood Volume (BV) Adaptations to Endurance Training
BV increases rapidly with endurance training
Plasma volume increases due to:
Increased plasma proteins (albumin)
Increased antidiuretic hormone and aldosterone
Red blood cell volume increases
Hemoglobin increases

28. Increases in Total Blood Volume and Plasma Volume With Endurance Training

29. Blood Flow, Pressure, and Volume Adaptations to Endurance Training
Key Points
Blood flow to active muscles is increased due to:
↑ Capillarization
↑ Capillary recruitment
More effective redistribution
↑ Blood volume
Blood pressure at rest as well as during submaximal exercise is reduced, but not at maximal exercise
(continued)

30. Blood Flow, Pressure, and Volume Adaptations to Endurance Training (continued)
Key Points
Blood volume increases
Plasma volume increases through increased protein content and by fluid conservation hormones
Red blood cell volume and hemoglobin increase
Blood viscosity decreases due to the increase in plasma volume

31. Respiratory Adaptations to Endurance Training
Key Points
Little effect on lung structure and function at rest
Increase in pulmonary ventilation during maximal exercise
↑ Tidal volume
↑ Respiratory rate
Pulmonary diffusion increases at maximal exercise due to increased ventilation and lung perfusion
(a-v)O2 difference increases with training, reflecting increased extraction of oxygen at the tissues

32. Adaptations in Muscle to Endurance Training
Increased size (cross-sectional area) of type I fibers
Transition of type IIx → type IIa fiber characteristics
Transition of type II → type I fiber characteristics
Increased number of capillaries per muscle fiber and for a given cross-sectional area of muscle
Increased myoglobin content of muscle by 75% to 80%
Increased number, size, and oxidative enzyme activity of mitochondria

33. Change in Maximal Oxygen Uptake and SDH Activity With Endurance Training

34. Gastrocnemius Oxidative Enzyme Activities of Untrained (UT) Subjects, Moderately Trained (MT) Joggers, and Highly Trained (HT) Runners
Adapted, by permission, from D.L. Costill et al., 1979, "Lipid metabolism in skeletal muscle of endurance-trained males and females," Journal of Applied Physiology 28: and from D.L. Costill et al., 1979, "Adaptations in skeletal muscle following strength training," Journal of Applied Physiology 46:

35. Adaptations in Muscle With Training
Key Points
Type I fibers tend to enlarge
Increase in type I fibers and a transition from type IIx to type IIa fibers
Increased number of capillaries supplying each muscle fiber
Increase in the number and size of muscle fiber mitochondria
Oxidative enzyme activity increases
Increased capacity of oxidative metabolism

36. Metabolic Adaptations to Training
Lactate threshold increases due to:
Increased clearance and/or decreased production of lactate
Reduced reliance on glycolytic systems
Respiratory exchange ratio decreases due to:
Increased utilization of free fatty acids
Oxygen consumption (VO2)
Unchanged (or slightly reduced) at submaximal intensities
VO2max increases
Limited by the ability of the cardiovascular system to deliver oxygen to active muscles . .

37. Changes in Lactate Threshold With Training

38. (continued)

39. (continued)

40. Changes in Race Pace With Continued Training After VO2max Stops Increasing.

41. Increased Performance After VO2max Has Peaked.
Once an athlete has achieved her genetically determined peak VO2max, she can still increase her endurance performance due to the body’s ability to perform at increasingly higher percentages of that VO2max for extended periods. The increase in performance without an increase in VO2max is a result of an increase in lactate threshold. . . .

42. Factors Affecting VO2max.
Factors Affecting VO2max
Level of conditioning: Initial state of conditioning will determine how much VO2max will increase (i.e., the higher the initial value, the smaller the expected increase)
Heredity: Accounts for 25-50% of the variation in VO2max
Sex: Women have lower VO2max compared to men
Individual responsiveness: There are high responders and low responders to endurance training, which is a genetic phenomenon . . .

43. Comparisons of VO2max in Twins and Nontwin Brothers.
Comparisons of VO2max in Twins and Nontwin Brothers
Adapted, by permission, from C. Bouchard et al., 1986, “Aerobic performance in brothers, dizygotic and monozygotic twins,” Medicine and Science in Sports and Exercise 18:

44. (continued)

45. (continued)

46. Variations in the Percentage Increase in VO2max for Identical Twins.
From D. Prud'homme et al., 1984, “Sensitivity of maximal aerobic power to training is genotype-dependent,” Medicine and Science in Sports and Exercise 16(5): Copyright 1984 by American College of Sports Medicine. Adapted by permission.

47. .
Variations in the Improvement in VO2max Following 20 Weeks of Endurance Training .
Adapted, by permission, from C. Bouchard et al., 1999, “Familial aggregation of VO2max response to exercise training: Results from HERITAGE Family Study,” Journal of Applied Physiology 87:

48. Cardiorespiratory Endurance and Performance
It is the major defense against fatigue
Should be the primary emphasis of training for health and fitness
All athletes can benefit from maximizing their endurance

49. Adaptations to Aerobic Training
Key Points
Although VO2max has an upper limit, endurance performance can continue to improve
An individual’s genetic makeup predetermines a range for his or her VO2max and accounts for 25-50% of the variance in VO2max
Heredity largely explains an individual’s response to training
Highly conditioned female endurance athletes have VO2max values about 10% lower than their male counterparts
All athletes can benefit from maximizing their cardiorespiratory endurance . . . .

50. Summary of Cardiovascular Adaptation to Chronic Endurance Training
Adapted, by permission, from Donna H. Korzick, Pennsylvania State University, 2006.

51. Muscle Adaptations to Anaerobic Training
Increased muscle fiber recruitment
Increased cross-sectional area of type IIa and type IIx muscle fibers

52. Energy System Adaptations to Anaerobic Training
Increased ATP-PCr system enzyme activity
Increased activity of several key glycolytic enzymes
No effect on oxidative enzyme activity

53. Changes in Creatine Kinase (CK) and Myokinase (MK) Activities With Anaerobic Training

54. Performance in a 60 s Sprint Bout After Anaerobic Training

55. Anaerobic Training Key Points
Anaerobic training bouts improve both anaerobic power and anaerobic capacity
Increased performance with anaerobic training is attributed to strength gains
Increases ATP-PCr and glycolytic enzymes

57. Specificity of Training and Cross-Training
To maximize cardiorespiratory gains from training, the training should be specific to the type of activity that the athlete usually performs
Cross-training is training for more than one sport at a time
Gains in muscular strength and power are less when strength training is combined with endurance training

58. .
VO2max Values During Uphill Treadmill Running vs. Sport-Specific Activities in Selected Groups of Athletes
Adapted, by permission, from S.B. Strømme, F. Ingjer, and H.D. Meen, 1977, “Assessment of maximal aerobic power in specifically trained athletes,” Journal of Applied Physiology 42: