1. Cardiorespiratory Endurance
Chapter
Cardiorespiratory Endurance

2. Cardiorespiratory Endurance
Basic Physiology of Cardiorespiratory Endurance Exercise
Benefits of Cardiorespiratory Exercise
Assessing Cardiorespiratory Fitness
Developing a Cardiorespiratory Endurance Program
Exercise Safety and Injury Prevention

3. The Cardiorespiratory System
Cardiorespiratory system: system that circulates blood through the body; consists of the heart, blood vessels, and respiratory system

4. The Cardiorespiratory System
The heart
Fist-sized muscle with four chambers
Pulmonary circulation: circulatory system that moves blood between the heart and the lungs; controlled by the right side of the heart
Systemic circulation: circulatory system that moves blood between the heart and the rest of the body; controlled by the left side of the heart

5. The Cardiorespiratory System
The heart
Waste-laden, oxygen-poor blood travels through venae cavae, into the heart’s right upper changer, or atrium
After the right atrium fills, it contracts and pumps blood into the heart’s right lower chamber, or ventricle
Venae cavae: The large veins through which blood is returned to the right atrium of the heart

6. The Cardiorespiratory System
The heart
Atrium: The right upper chamber of the heart in which blood collects before passing to the ventricles (pl atria)
Ventricle: right lower chamber of heart from which blood flows through arteries to the lungs and other parts of the body
Diffusion: process of oxygen moving from lungs to the blood and carbon dioxide moving from blood to the lungs

7. The Cardiorespiratory System
The heart
Aorta: The body’s large artery; receives blood from the left ventricle and distributes it to the body
Systole: Contraction of the heart
Diastole: Relaxation of the heart
Blood pressure: The force exerted by the blood on the walls of the blood vessels; created by the pumping action of the heart

8. FIGURE 3.1 Chambers of the heart

9. The Cardiorespiratory System
Blood vessels
Blood vessels classified by size and function
Veins: Vessels that carry blood to the heart
Arteries: Vessels that carry blood away from the heart

10. The Cardiorespiratory System
Blood vessels
Endothelial cells: Cells lining the blood vessels
Nitric oxide: A gas released by the endothelial cells to promote blood flow
Capillaries: Very small blood vessels that distribute blood to all parts of the body
Coronary arteries: Pair of large blood vessels that branch off aorta and supply the heart muscle with oxygenated blood

11. The Cardiorespiratory System
The Respiratory System
Respiratory system: The lungs, air passages, and breathing muscles; supplies oxygen to the body and removes carbon dioxide
Alveoli: Tiny air sacs in the lungs that allow the exchange of oxygen and carbon dioxide between the lungs and blood

12. The Cardiorespiratory System
The Cardiorespiratory System at rest and during exercise
At rest, your heart beats at a rate of about 50 to 90 beats per minute, and you take about 12 to 20 breaths per minute
Stroke volume: amount of blood the heart pumps with each beat
Cardiac output: amount of blood pumped by the heart each minute; a function of heart rate and stroke volume

13. Energy Production Metabolic rate: rate at which body uses energy
Energy from food
Carbohydrates, fats, and proteins
Glucose: Simple sugar that circulates in blood and is used by cells to fuel ATP production
Glycogen: Complex carbohydrate stored in the liver and skeletal muscles; the major fuel source during most forms of intense exercise
Glycogen is the storage form of glucose

14. Energy Production
ATP (adenosine triphosphate): the energy “currency” of cells
Adenosine triphosphate (ATP): Energy source for cellular processes
Cells store small amount of ATP
When they need more, they create it through chemical reactions using body’s stored fuels—glucose, glycogen, and fat

15. Exercise and the Three Energy Systems
Immediate (“explosive”) energy system: Supplies energy to muscle cells through breakdown of cellular stores of ATP and CP

16. Exercise and the Three Energy Systems
Nonoxidative (anaerobic) energy system: Supplies energy to muscle cells through breakdown of muscle stores of glucose and glycogen; also called the anaerobic system or the lactic acid system
Anaerobic: Occurring in the absence of oxygen
Lactic acid: Metabolic acid resulting from the metabolism of glucose and glycogen

17. Exercise and the Three Energy Systems
Oxidative (aerobic) energy system: Supplies energy to cells through breakdown of glucose, glycogen, and fats; also called the aerobic system
Aerobic: Dependent on the presence of oxygen
Mitochondria: Cell structures that convert the energy in food to a form the body can use

18. Exercise and the Three Energy Systems
Maximal oxygen consumption (VO2max): Highest rate of oxygen consumption an individual is capable of during maximum physical effort, reflecting the body’s ability to transport and use oxygen; measured in milliliters of oxygen used per minute per kilogram of body weight

19. Exercise and the Three Energy Systems
The energy system in combination
Intensity and duration of exercise determines which energy system predominates
Physical fitness and energy production
Fitness program should target energy system most important to your goals
Cardiorespiratory system is the key to overall fitness

20. Benefits of Cardiorespiratory Endurance Exercise
Cardiorespiratory endurance exercise helps the body:
Become more efficient
Cope better with physical challenges
Resist chronic diseases

21. FIGURE 3.2 Immediate and long-term effects of regular cardiorespiratory endurance exercise

22. Improved Cardiorespiratory Functioning
Endurance exercises enhance heart health:
Maintaining or increasing the heart’s blood and oxygen supply
Improving the heart muscle’s function
Strengthening the heart’s contraction
Increasing the heart’s cavity size
Increasing blood volume
Reducing blood pressure

23. Improving Cellular Metabolism
Regular endurance exercise improves metabolism
Increases capillaries in muscles
Allows training muscles to make the most of oxygen and fuel
Increases mitochondria
Prevents glycogen depletion

24. Reduced Risk of Chronic Disease
Cardiovascular Diseases
Cancer
Type 2 Diabetes
Osteoporosis
Inflammation
Inflammation: body’s response to tissue and cell damage, environmental poisons, or poor metabolic health
Deaths from all causes
Physically fit people have reduced risk of dying prematurely

25. Better Control of Body Fat
Regular exercise increases daily calorie expenditure
Exercise increases resting metabolic rate
Improved immune function
Immune system: The physiological processes that protect us from diseases such as colds, bacterial infections, and even cancer
Exercise increases immune function

26. FIGURE 3.3 Survival rates for older adults doing vigorous, moderate, or no exercise, 1992–2008
SOURCE: Wen, M, et al 2013 Physical activity and mortality among middle-aged and older adults in the United States Journal Physical Activity & Health Published online

27. Improved Psychological and Emotional Well-Being
Performing physical activities provides proof of skill mastery and self-control
Endurance exercises lessen anxiety, depression, stress, anger, and hostility, while improving sleep

28. Choosing an Assessment Test
The 1-Mile Walk Test
Estimates level of maximal oxygen consumption based on time it takes to complete one mile of brisk walking and the heart rate at the end of the walk
The 3-Minute Step Test
Measures how long it takes the pulse to return to normal after three minutes of stepping exercise

29. Choosing an Assessment Test
The 15-Mile Run-Walk Test
Oxygen consumption increases with speed
The Beep Test
A prerecorded series of tones sound off at faster and faster intervals, and the exerciser must keep up with the beeps
Monitoring Your Heart Rate
Measure your heart rate using a heart rate monitor or counting your pulse beats
Interpreting Your Score

30. FIGURE 3.4 Checking your pulse

31. Developing a Cardiorespiratory Endurance Program
Set realistic goals
Set starting frequency, intensity, and duration of exercise at appropriate levels
Choose suitable activities
Warm up and cool down
Adjust program as fitness improves

32. Setting Goals Set “SMART” goals Specific Measurable Attainable
Realistic
Time frame-specific

33. Applying the FITT Equation
Frequency of Training
Experts recommend 3 to 5 days per week
Intensity of Training
Target heart rate zone: Heart rates that should be reached and maintained during cardiorespiratory endurance exercise to obtain training effects
Heart rate reserve: Difference between maximum heart rate and resting heart rate

34. Applying the FITT Equation
Intensity of training
MET: Unit of measure that represents body’s resting metabolic rate
Ratings of perceived exertion (RPE): System of monitoring exercise intensity based on assigning a number to the subjective perception of target intensity
Talk test

35. Applying the FITT Equation
Time (duration) of training
Total duration of 20 to 60 minutes per day recommended
Type of activity
Cardiorespiratory endurance exercises include activities that involve rhythmic use of large muscle groups for an extended period of time

36. FIGURE 3.5 Ratings of perceived exertion (RPE)
SOURCE: Pick, H L, ed 1978 Psychology from Research to Practice Kluwer Academic/Plenum Publishing Corporation With kind permission of Springer Science and Business Media and the author

37. TABLE 3.2 Target Heart Rate Zone and 10-Second Counts

38. TABLE 3.3 Approximate MET and Caloric Costs of Selected Activities for a 154-Pound Person

39. FIGURE 3.6 The FITT principle for a cardiorespiratory endurance workout

40. TABLE 3.4 Estimating Exercise Intensity

41. TABLE 3.5 Sample Progression for an Endurance Program

42. Warming Up and Cooling Down
Warm-up session should include low-intensity, whole body movements similar to those in the activity that will follow
Do not use stretching as part of pre-exercise warm-up
Cooling down returns the body to a non-exercising state

43. Building Cardiorespiratory Fitness
You must increase the intensity, frequency, and duration of exercise carefully to avoid injury and overtraining
Keep an exercise log or training diary
Maintaining cardiorespiratory fitness
Cross-training: Alternating two or more activities to improve a single component of fitness

44. Exercise Safety and Prevention
Hot weather and heat stress
Dehydration: Excessive loss of body fluid
Heat cramps: Sudden muscle spasms and pain associated with intense exercise in hot weather
Heat exhaustion: Illness resulting from exertion in hot weather
Heatstroke: A severe and often fatal heat illness characterized by significantly elevated core body temperature

45. FIGURE 3.5 Urine chart to assess dehydration
SOURCE: Casa, D J, et al April–June 2000 National Athletic Trainers’ Association position statement: Fluid replacement for athletes Journal of Athletic Training 35(2): 212–224, 224a

46. Exercise Safety and Prevention
Cold weather
Hypothermia: Low body temperature due to exposure to cold conditions
Frostbite: Freezing of body tissues characterized by pallor, numbness, and a loss of cold sensation
Wind chill: Measure of how cold it feels based on the rate of heat loss from exposed skin caused by cold and wind
Poor air quality

47. Exercise Injuries Consult a physician for the following:
Head and eye injuries
Possible ligament injuries
Broken bones
Internal disorders such as chest pain, fainting, and heat intolerance

48. Exercise Injuries Managing minor exercise injuries
For cuts and scrapes, stop the bleeding and clean the wound
For injuries to muscles and joints, use RICE
Rest
Ice
Compression
Elevation

49. Exercise Injuries Preventing injuries
Train regularly and stay in condition
Gradually increase the intensity, duration, or frequency of workouts
Avoid or minimize high-impact activities
Get proper rest between exercise sessions
Drink plenty of fluids
Warm up thoroughly before you exercise and cool down afterward

50. Exercise Injuries Preventing injuries
Achieve and maintain a normal range of motion in your joints
Use proper body mechanics
Don’t exercise when you are ill or overtrained
Use proper equipment
Don’t return to your normal exercise program until athletic injuries have healed