1. Chapter 4 cardiorespiratory fitness

2. COMING UP IN THIS CHAPTER
Learn how your cardiorespiratory system works and what affects its functioning
Discover the benefits of cardiorespiratory fitness
Assess your level of cardiorespiratory fitness
Develop a personalized cardiorespiratory fitness program

3. Factors Affecting Cardiorespiratory Fitness
Cardiorespiratory fitness (CRF)
The ability of the circulatory and respiratory systems to sustain physical activity
Also known as cardiorespiratory endurance, aerobic fitness, or aerobic endurance

4. Factors Affecting Cardiorespiratory Fitness
I have a friend on the track team. I tried running with her once and it was so hard. Why is it so easy for her?
Things to consider:
Genes
Health
Cardiorespiratory (CR) conditioning
Nutrition
Training

5. The Condition of the Cardiorespiratory System
What are the parts of the system that make my muscles go?
Major components of the cardiorespiratory (CR) system:
Heart
Lungs
Network of blood vessels (vascular system)

6. The Condition of the Cardiorespiratory System
Heart
Acts as muscle pump to circulate blood
Lungs
Take in oxygen and expel carbon dioxide; exchange takes place in the alveoli
Respiratory system: air passages, lungs, breathing muscles

7. The Condition of the Cardiorespiratory System
Vascular system
Circulates blood to lungs and around body
Arteries: carry blood away from heart
Veins: carry blood toward the heart
Capillaries: tiny blood vessels with thin walls; substances can pass between the blood they carry and the surrounding cells and tissues

8. Figure 4-1 The cardiorespiratory system

9. Figure 4-2 Circulation of oxygen and carbon dioxide

10. The Condition of the Cardiorespiratory System
When I try to run fast, why does it feel like I can’t breathe?
As exercise intensifies, CO2 and lactate (lactic acid) accumulate
Increased ventilation lowers both
In fit individuals, this effect is lessened
Increased CR system efficiency is directly related to increased training

11. Figure 4-3 Increase in breathing rate during exercise

12. The Condition of the Cardiorespiratory System
Can I eat before I exercise?
It depends on the type of exercise
Exercise redirects blood to active muscles
Less blood to the gut to help digest
Can result in “side stitch”

13. Energy Production
I feel tired all the time. What can I do to get more energy?
Energy level versus energy production:
Adenosine triphosphate (ATP) is fuel for muscles
Catabolism
ATP is produced from carbohydrate, fat, or protein
Carbohydrates are the main source
Converted to ATP from blood glucose or from carbohydrates stored in the liver and skeletal muscle (glycogen)

14. Energy Production
Carbohydrates (glucose or glycogen) are stored in limited amounts, but are the most readily converted
Preferred energy source for ATP
Fats have unlimited storage but do not convert readily to ATP
Beta-oxidation
Protein has limited storage; it is inefficient for energy conversion
Distant third choice for energy

15. Energy Production
The three energy systems that can produce ATP and generate energy:
ATP/CP energy system
Short duration, less than 10 seconds
Glycolytic energy system
Activities that last longer than 10 seconds
Aerobic energy system
Occurring in the presence of oxygen

16. Energy Production ATP/CP energy system When the body needs energy fast
Anaerobic
Ideally suited for extremely short bouts of activity
Jumping, throwing, lifting, sprinting
Can replenish itself rapidly
Fueled by stored ATP and creatine phosphate (CP)
Stored creatine is critical
Red meat is the best source of this compound

17. Energy Production Glycolytic energy system
This system will take over when activities last more than 10 seconds
Anaerobic
Glycolysis
Pyruvate (pyruvic acid)
Can be converted to lactate under certain conditions
Relatively inefficient at generating ATP
Best suited for activities that last up to 90 seconds

18. Energy Production
How is aerobic exercise different, and why is it so important?
To build cardiorespiratory fitness (CRF), you’ll need to perform activities that primarily use the oxygen-dependent aerobic energy system
It does not produce ATP fast enough for a brief, all-out intense effort
When oxygen is present, the potential for ATP production increases dramatically when compared to the other systems
Mitochondria

19. Figure 4-4 Time span of action of the three energy systems

20. Diseases Affecting the Cardiorespiratory System
Can you still achieve cardio fitness if you have something like asthma? Is cardio exercise safe after a heart attack?
Asthma and COPD (chronic bronchitis and emphysema)
Can exercise; but frequency, intensity, duration, and type of exercise may be restricted
Cardiovascular disease
Exercise is critical in both primary and secondary prevention

21. Genetics
I don’t like to exercise, and neither do my parents. Is my problem genetic?
How much you like exercise not affected by genes, but genetics may play role in your ability to get fit
No more than 50% of your ability to improve your cardio respiratory fitness is inherited
The other half is based on how active we are and what activities we engage in

22. Biological Sex How do men and women differ in getting fit?
Men and women have the same ability to increase their levels of cardiorespiratory fitness
Men can typically achieve a higher absolute level of cardiorespiratory function
Difference is in size between the sexes

23. Use and Age My dad is 58 and wants to start exercising. Is he too old?
It is never too late to start a fitness program
A natural result of aging is a steady decline in the functioning of the cardiorespiratory system
The rate of decline is lower in those who exercise on a regular basis
“Use it or lose it”

24. Improved Performance
My boyfriend made me do an online fitness survey and it said my VO2 was 41. What does that mean?
VO2: volume of oxygen consumed over time
Largely determined by the amount of oxygen you bring into your lungs, which is affected by size
VO2max: maximum amount of oxygen you can consume during peak exercise

25. Improved Performance
Every time I start an exercise program I feel worse! Does it ever get better?
Start gradually
Over time:
Your heart muscle will grow stronger
Your lungs will become more efficient
Your blood vessels will become more elastic
Your cells will develop more mitochondria

26. Improved Performance If your heart is a muscle, can you bulk it up?
The heart can grow in size (hypertrophy)
Regular exercise allows the heart muscle to stay flexible
Greater stroke volume
Higher cardiac output

27. Reduced Risk of Disease
My mom’s doctor told her to walk every day to help lower her blood pressure. Does just walking really work?
Positive effects of physical exercise:
Improved blood pressure
Improved cholesterol levels
Reduced risk of type 2 diabetes
Reduced risk of certain cancers
Reduced risk of osteoporosis
Reduced risk of cardiovascular disease (CVD)

28. Figure 4-5 Summary of the effects of cardiorespiratory exercise

29. Reduced Risk of Disease
Will exercise make me live longer?
Regular cardiorespiratory exercise may increase longevity and quality of life

30. Healthier Body Composition
How much exercise do I need if I want to lose some serious weight before spring break? And what is the best weight-loss exercise?
Healthy weight loss is 1–2 pounds per week
A one-pound change in body weight represents a change of 3,500 calories through diet, exercise, or both
The best choice of exercise is one that you will do regularly

31. Stress Management and Improved Emotional Wellness
I feel better after exercising. Why is that?
Almost any type of physical activity, moderate in duration and intensity, can cause feelings of elation
Provides distraction
Increases body temperature
Changes brain chemistry

32. Types of Cardiorespiratory Fitness Tests
How do my friend and I figure out who is more fit?
Take the same type of CRF assessment
Lab tests
Field tests
Resting heart rate assessment
The usual point is for motivation

33. Types of Cardiorespiratory Fitness Tests
Lab tests
Measure VO2 accurately
Metabolic cart
Field tests
Rockport walk test
Walk a mile as quickly as possible
1.5-mile run/walk test
3 minute step test
See Lab Activity 4-1

34. Types of Cardiorespiratory Fitness Tests
Resting heart rate
Measuring your true RHR doesn’t involve exercise at all
Heart rate is counted for 1 full minute after waking

35. Evaluating Assessment Results and Setting Goals
How much can I improve? How much do I really need to improve?
Improvement varies
Aerobic capacity can increase by 10–30%
It is best to progress no more than 10% a week in frequency, intensity, or time (not all at once)
Recall the principle of progressive overload

36. Evaluating Assessment Results and Setting Goals
How often should I do an assessment to check for improvement in my cardio fitness? Can I judge my fitness without taking a test?
Achieve goals, then set new ones
Re-assess your fitness 4–6 weeks initially and then every 8–12 weeks
Use your exercise performance as a guide
Get baseline measurements

37. Getting Started
How do I learn to like exercise? Right now, I just don’t.
For a successful cardiorespiratory fitness program:
Apply the FITT formula
Include activities you enjoy and will stick with
Finding exercise you like is most important

38. Applying the FITT Formula
How do I know I’m doing the right things— not going too far, or too fast, or too slow?
Use the FITT formula:
Frequency
Intensity
Time
Type

39. The FITT Formula: Frequency
Is it safe to work out every day?
Most guidelines encourage 1–2 days of rest to prevent injury and burnout
Daily is fine if you vary routine, exercises, intensity
Intensity and frequency need to be balanced
ASCM: 3 days a week for vigorous intensity (for at least 20 minutes a day) and 5 days a week for moderate intensity
Bouts of at least 10 minutes count toward the minimum- duration recommendation

40. The FITT Formula: Intensity
How hard should I exercise?
Exercise in your target intensity zone
Balance with frequency and duration
Intensity is tied to your personal goals
Difference between moderate-intensity and vigorous-intensity:
Two minutes of moderate activity confers the same benefit as one minute of vigorous activity

41. The FITT Formula: Intensity
What’s considered moderate activity and vigorous activity?
The talk test is a simple method for judging intensity
Moderate-intensity exercise: you can talk but not sing
Vigorous-intensity exercise: you can say only a few words before pausing to take a breath
More…

42. The FITT Formula: Intensity
Other methods for judging intensity:
Heart-rate maximum method (HRmax)
Exercising at certain percentage of maximum heart rate (MHR)
Target heart rate = MHR × %
Can also use age; subtracting age from 220
Target heart-rate range
More…

43. The FITT Formula: Intensity
Heart-rate reserve (HRR) method
More complicated but more accurate
Target heart rate = [(MHR – RHR) × %] + RHR
RHR determined by counting pulse before you get out of bed
Rating of perceived exertion (RPE)
Subjective measure of exercise intensity
Rate on scale of 6 to 20
Metabolic equivalents (METs)
Estimates amount of oxygen body uses during physical activity

44. Table 4-1 Recommended Starting Intensity Of Exercise Based on Current Activity Level

45. Figure 4-7 Rating of perceived exertion (RPE) scale

46. Applying the FITT Formula
What’s the best way to take my heart rate when I’m exercising?
Heart-rate monitor
Fingers on the inside of the wrist at the radial artery or on the neck by the carotid artery

47. Applying the FITT Formula
Doesn’t lower-intensity exercise burn more fat?
What matters is total calories used
Lower intensity uses more fat; higher intensity uses more overall calories and total fat

48. Figure 4-8 Intensity Levels of different physical activities

49. Figure 4-9 Fat and carbohydrate used during exercise

50. The FITT Formula: Time
How many hours of cardiovascular activity are necessary to be healthy?
Balance time with intensity
Individual workouts and weekly exercise plan:
ACSM: moderate-intensity exercise at least 30 minutes/day, 5 or more days/week; or 20 minutes of vigorous exercise, 3 days a week
HHS: 150 minutes of moderate-intensity or 75 minutes of vigorous intensity (doubling brings even greater health)
Beware of time spent sitting

51. Figure 4-10 Relationship between exercise time and intensity

52. The FITT Formula: Type
Cardiorespiratory fitness can improve through a variety of activities
Those that are aerobic, rhythmic, and involve regularly performed work by large muscle groups
Individual activities and team “pick-up” activities
Outside or in the gym

53. Putting Together a Complete Workout
Do I really need a warm-up just to go walking with my friends?
No; because you will probably start off slower and increase speed as you go (you will in fact be warming up)
A workout has three stages:
Warm-up
Conditioning
Cool-down

54. Figure 4-11 Cardiorespiratory workout

55. Making FITT Work for You
I don’t have much time to work out but I still want to get fit. What can I do?
You need to consider your:
Current level of fitness
Schedule
Activity options
Preferences
Goals

56. Table 4-2 Summary of Recommended Exercise Guidelines

57. Making Progress Toward Your Fitness Goals
How long until I can run for 5 miles?
Choose proper progression

58. Making Progress Toward Your Fitness Goals
Do I need a special diet to increase cardio fitness?
Diet can’t directly increase CRF, but it can go a long way in improving overall health
Fitness gains come from training
Diet impacts the quality of training

59. Making Exercise Safe I have a cold. Can I still work out?
Yes, if you don’t have a fever and your symptoms are from the neck up
Maybe at a slower pace or for a shorter duration
If you have the flu, take time off and start back slowly

60. Personal Training Online, in Person, or Somewhere in Between?
How do I know who is a good personal trainer?
Look for certification and a relevant degree
Ask for references
Check the fees
Read the fine print
Discuss expectations

61. Fine-Tuning Your Program to Maintain Success and Enjoyment
Is there anything in particular I should keep track of over time?
Setting goals and tracking progress are good strategies for success
You can track your miles, minutes, days per week, heart rate, RPE, etc.
It helps in seeing your progress and in identifying problems

62. Fine-Tuning Your Program to Maintain Success and Enjoyment
I get bored easily. Any suggestions?
Investigate boredom-busting technology
Add faster or higher intensity spurts (interval training)
Cross-training
Investigate skill-related sports

63. Sticking with Your Program—and Restarting It After a Lapse
How am I supposed to stick with exercise over time? I’ve never had much luck.
Maintaining an exercise program is the hard part
Have a plan to prevent relapses
6–12 weeks before exercise becomes a routine

64. Sticking with Your Program—and Restarting It After a Lapse
How do I find more time to exercise?
Keep a time log to identify time to exercise
Fit mini-exercises into the day

65. Sticking with Your Program—and Restarting It After a Lapse
I used to exercise but haven’t for a while. What would you recommend for me since I’m just getting back into working out?
Start back slowly
Focus on progression without increasing too much or too fast