1. Cardiorespiratory Endurance6
Cardiorespiratory Endurance

2. Cardiorespiratory Endurance
Ability of lungs, heart, and blood vessels to deliver enough oxygen to cells to meet demands of prolonged physical activity
The most important part of health-related physical fitness
Lack of physical activity leads to hypokinetic diseases such as hypertension, heart disease, chronic low back pain, and obesity
Aerobic exercise is especially important in preventing cardiovascular disease

3. Basic Cardiorespiratory Physiology
CR endurance measures how pulmonary, cardiovascular, and muscular systems work together during aerobic activities
Oxygen taken up by alveoli in the lungs and transported in blood hemoglobin, and then through the circulatory system
Oxygen converts food into ATP through aerobic metabolism
Oxygen uptake, or VO2 – indicates more efficient CR system

4. Key Terms Alveoli Hemoglobin
Air sacs in the lungs where oxygen is taken up and carbon dioxide (produced by the body) is released from the blood
Hemoglobin
Iron-containing compound, found in red blood cells, that transports oxygen

5. Key Terms Adenosine triphosphate (ATP) Oxygen uptake (VO2)
A high-energy chemical compound that the body uses for immediate energy
Oxygen uptake (VO2)
The amount of oxygen the human body uses

6. Aerobic and Anaerobic Exercise
Cardiorespiratory endurance activities are called aerobic exercises
Requires oxygen to produce energy (ATP) to carry out the activity
Examples: walking, jogging, swimming
Anaerobic exercise is so intense that oxygen can’t be delivered and used to produce energy
Does not require oxygen to produce the necessary energy (ATP) to carry out the activity.

7. Benefits of Aerobic Training
Higher maximal oxygen uptake (VO2max)
Increase in oxygen-carrying capacity of blood
Decrease in resting heart rate (RHR)
Increase in cardiac output and stroke volume
Cardiac output: amount of blood pumped by the heart in one minute
Stroke volume: amount of blood pumped by the heart in one beat

8. Benefits of Aerobic Training (cont’d.)
Beneficial physiological adaptations (cont’d.)
Lower heart rate at given workloads
Load placed on body during physical activity
Increase in number, size, and capacity of mitochondria
Structures within cells where energy transformations take place
Increase in number of functional capillaries
Smallest blood vessels carrying oxygenated blood to the body

9. Benefits of Aerobic Training (cont’d.)
Beneficial physiological adaptations (cont’d.)
Faster recovery time after exercising
Time the body takes to return to resting levels after exercise
Lower blood pressure and blood lipids
Increase in fat-burning enzymes

10. Critical Thinking

11. Physical Fitness Assessment
Assessment serves several purposes:
Educate participants about current fitness levels
Motivate individuals
Provide starting point
Evaluate improvements in fitness
Monitor changes throughout the years

12. Responders versus Nonresponders
Principle of individuality: genetics play a role in response to exercise
Responders readily show improvements
Nonresponders exhibit small or no improvements at all
A lower-body strength-training program has been shown to help nonresponders improve VO2max through aerobic exercise

13. Assessment of Cardiorespiratory Endurance
Aerobic capacity determined by oxygen uptake per minute of physical activity (VO2max)
Higher levels = greater efficiency
Relative value in mL/kg/min is used most often

14. Assessment of Cardiorespiratory Endurance (cont’d.)
Components of VO2max
Heart rate (beats per minute) and maximal heart rate (MHR)
Stroke volume (mL per beat)
Amount of oxygen removed from blood
(mL of O2 per 100 cc of blood)
Arterial-venous oxygen difference (a-vO2diff)

15. Key Terms Maximal heart rate (MHR) Arterial-venous oxygen difference
Highest heart rate for a person, related primarily to age
Arterial-venous oxygen difference
Amount of oxygen removed from the blood as determined by the difference in oxygen content between arterial and venous blood

16. Assessment of Cardiorespiratory Endurance (cont’d.)
VO2 is computed using the following equation:
VO2 in L/min = (HR x SV x a-vO2diff) ÷ 100,000
HR = heart rate
SV = stroke volume
VO2max is affected by genetics, training, gender, age, and body composition
VO2max decreases 1% per year starting at age 25
0.5% per year in physically active individuals

17. Tests to Estimate VO2max
Five tests used to assess CR fitness:
1.5-Mile Run Test
1.0-Mile Walk Test
For those unable to run; heart rate of at least 120 bpm
Step Test
Astrand-Rhyming Test
12-Minute Swim Test

18. 1.5-Mile Run Test
Figure 6.2. Procedure for the 1.5-mile run test.

19. 1.0-Mile Walk Test
Figure 6.3. Procedure for the 1.0-mile walk test.

20. Step Test
Figure 6.4. Procedure for the Step Test.

21. Astrand–Rhyming Test
Figure 6.5. Procedure for the Astrand-Rhyming Test.

22. 12-Minute Swim Test
Figure 6.6. Procedure for the 12-minute swim test.

23. Critical Thinking

24. Interpreting the Results
After obtaining VO2max, you can determine your current level of CR fitness
Locate the VO2max in your age category, and find your present level of CR fitness on the top row

25. Cardiorespiratory Fitness Classification
Table 6.8. Cardiorespiratory Fitness Classification According to Maximal Oxygen Uptake (VO2max)

26. Principles of CR Exercise Prescription
Adherence to exercise is enhanced if you are able to make it through 4 to 6 weeks of training
The first step is to ask yourself: Am I ready to start an exercise program?

27. Guidelines for CR Exercise Prescription
To develop the CR system, the heart muscle has to be overloaded
FITT-VP
Frequency
Intensity
Time (duration)
Type (mode)
Volume
Progression

28. Intensity of Exercise
Cardiorespiratory stimulation: make heart pump faster for a specified time period
Health and fitness benefits
30 to 85% of heart rate reserve (HRR)
Appropriate duration and frequency

29. Intensity of Exercise (cont’d.)
Determine the intensity of exercise or cardiorespiratory training zone:
MHR = 207 – (.7 x age)
HRR = MHR – RHR
Calculate TIs at 30, 40, 50, 60, 70, 85%
% TI = [HRR x (%)] + RHR

30. Key Terms FITT-VP Vigorous exercise Moderate exercise
Frequency, intensity, type, time, volume, progression
Vigorous exercise
High intensity level (>70% max)
Moderate exercise
Noticeably increases heart rate and breathing

31. Key Terms Heart rate reserve (HRR) Cardiorespiratory training zone
Maximal minus resting heart rate
Cardiorespiratory training zone
Recommended training intensity range to obtain adequate cardiorespiratory endurance development

32. Moderate- vs. Vigorous-Intensity Exercise
As intensity increases, adherence decreases, and injuries increase
Moderate-intensity physical activity (about 50 percent TI) provides many health benefits, including decreased risk for cardiovascular mortality
Vigorous-intensity programs yield higher improvements in VO2max

33. Recommended Cardiorespiratory or Aerobic Training Pattern
Figure 6.7. Recommended cardiorespiratory or aerobic training pattern.

34. Monitoring Exercise Heart Rate
Count your pulse for 10 seconds, then multiply by six to get the per minute pulse rate
Monitor regularly in beginning of program
Make sure you are in the proper zone
Assess activity level based on pulse rate
Consider personal fitness goals

35. Rate of Perceived Exertion (RPE)
A perception scale to monitor or interpret the intensity of aerobic exercise
Alternative to checking pulse
Rate of exercise difficulty
Cross-check with target zone
Reexamine periodically

36. Perceived Exertion Scale
Figure 6.9. Physical activity perceived exertion scale

37. Mode of Exercise
The mode, or type, of exercise that develops the CR system has to be aerobic in nature
Involves major muscle groups
Choose activities based on personal preferences

38. Mode of Exercise (cont’d.)
Optimal health benefits
Lower end of cardiorespiratory zone
Greater improvements
Higher end of cardiorespiratory zone
Specificity of training
Use same mode for exercise as testing

39. Duration of Exercise Exercise between 20 to 60 minutes per session
Up to 90 minutes daily may be required to prevent weight gain
Even accumulation of 30 min moderate activity, conducted for at least 10 minutes three times per day, benefits the CR system
5 hours of moderate activity, or 2.5 hours of vigorous activity per week provide additional benefits

40. Duration of Exercise (cont’d.)
Novice and overweight exercisers need proper conditioning prior to vigorous exercise to avoid injuries or cardiovascular-related problems
Exercise sessions always should be preceded by a 5- to 10-minute warm-up and be followed by a 10-minute cool-down period
A warm-up consists of general exercises at a lower intensity than the actual target zone

41. Frequency of Exercise
Recommended exercise frequency for aerobic exercise is 3 to 5 days per week
Three 20- to 30-minute exercise sessions per week, on nonconsecutive days, are sufficient to improve (in the early stages)
Endurance athletes may train at or above the anaerobic threshold

42. Key Terms Anaerobic threshold Volume of exercise
The highest percentage of the VO2max at which an individual can exercise (maximal steady state) for an extended time without accumulating significant amounts of lactic acid
Volume of exercise
The product of frequency, intensity, and duration
Minimum volume of 1000 calories per week recommended

43. Excessive Sitting: A Deadly Proposition
People who sit most of the day have up to a 50% greater risk of dying prematurely and an 80% greater risk of cardiovascular disease
Ways to enhance daily nonexercise activity thermogenesis (NEAT)
Stand as much as possible; use a standing or a treadmill desk; use a stability ball for a chair; hold “walking” meetings; walk to co-workers’ offices instead of phoning; take intermittent breaks; park farther away; take the stairs

44. Rate of Progression
Rate of progression depends on health status, exercise tolerance, and program goals
Initially, only three weekly training sessions of 15 to 20 minutes are recommended to avoid musculoskeletal injuries
Increase duration by 5-10 minutes per week and frequency up to 5 times per week by the fourth or fifth week
Progressively increase frequency, duration, and intensity of exercise until you reach your fitness maintenance goal

45. Physical Activity Pyramid
Figure The physical activity pyramid.

46. Fitness Benefits of Aerobic Activities
Effort determines benefits and physiological development
Beginners should start with light-intensity activities that carry a minimum risk for injuries
METs (metabolic equivalents) measure intensity of exercise in multiples of resting metabolic rate
1 MET is the equivalent of a VO2 of 3.5 mL/kg/min
MET levels for a given activity vary according to the effort expended

47. Getting Started The first few weeks are the most difficult
Reduce muscle soreness, stiffness, and risk for injuries by gradually increasing exercise intensity, duration, and frequency
Once you begin to see positive changes, it won’t be as hard

48. A Lifetime Commitment to Fitness
Benefits are maintained through a regular lifetime program
Four weeks of aerobic training are completely reversed in two weeks of physical inactivity
Staying with a physical fitness program long enough brings about positive physiological and psychological changes

49. Assess Yourself
Do you consciously attempt to incorporate as much physical activity as possible in your daily living?
Do you understand the following concepts?
Cardiorespiratory endurance training
Aerobic and anaerobic exercise
Assessing cardiorespiratory fitness
1.5-mile run test, 1.0-mile walk test, step test, Astrand-Rhyming test, 12-minute swim test