Chapter 6 - Cardiorespiratory Endurance Assessment

1. Introduction

• Cardiorespiratory Endurance ------ is the most important indicator of overall health
• Physical activity is no longer part of our existence
• This leads to hypokenic diseases- those associated with a sedentary lifestyle
  • Hypertension
  • Heart Disease
  • Low Back Pain
  • Obesity
• During physical exertion, the heart, lungs, and blood vessels must pump more blood (Oxygen) to the cells of the body

2. Aerobic / Anaerobic exercise

• Aerobic Exercise- Oxygen demands are low enough that the activity can be continued
  • Walking
  • Jogging
  • Swimming
  • Cycling
  • Etc.
• Anaerobic Exercise- The Intensity is high enough that there is not sufficient oxygen to continue
  • 100 Dash
  • 200 Dash
  • 400 Dash
• Only aerobic exercises contribute to Cardiorespiratory endurance

3. Benefits of Aerobic training

• Higher Max. Oxygen Uptake- The amount of oxygen the body is able to use during exercise
• Increase in oxygen carrying capacity of blood [number of red blood cells (hemoglobin) increase]
• Decrease In resting HR increase in cardiac muscle strength:

• (Cardiac output = increased stroke volume x decreased Heart Rate)

• Lower HR at given workloads
• Increase in the number and size of mitochondria (Produces energy)
• Increase in the number of functional capillaries
• Faster Recovery time
• Lower Blood Pressure and Blood lipids
• An increase in fat-burning enzymes

4. Assessment of Cardiorespiratory Endurance

1. Introduction

• Cardiorespiratory fitness (aerobic capacity) is determined by the maximum amount of oxygen the body is able to use per minute of physical activity.
• The most precise way to determine Max. Oxygen uptake is direct gas analysis
  • Requires costly equipment ---- alternate methods of measuring VO2 MAX
  • A physical should be present during most VO2Max tests.

• Alternate Tests:

1. 1.5 mile test
   • Predicts Cardiorespiratory based on time a person completes a 1.5 mile course
   • Should be limited to conditioned individuals
2. 1 mile walk test - requires a brisk walk of 1 mile
   • For individuals who cannot run --- You need to know how to check HR (pulse)
3. Step Test
   • 3 minutes of box (or bench) stepping followed by a HR check
   • Significantly overweight individuals or people with joint problems should not take this test.
4. Astrand-Ryhming test
   • Conducted on a bicycle ergometer with HR taken every 6 minutes
5. 12-minute swim test
   • Swim as far as possible in 12 minutes
   • You need a pre-test and post-test for validity (because many factors can affect results: Swimming ability, obesity, larger surface area [more friction])
6. University of Houston Non-exercise test
   • Method of Max Oxygen uptake without exercise measuring
   • Based on the findings that Max Oxygen uptake is related to AGE, BODY COMPOSITION, and EXERCISE HABITS.

5. Interpreting Max Oxygen Uptake results

You can use your Max Oxygen Uptake results to determine your current level of Cardiorespiratory fitness by consulting Table 6.8

6. HR and Blood Pressure Assessment

• HR can be obtained by counting your pulse at the radial artery (wrist) or carotid artery (neck)
  • Count for 30 seconds and multiply by 2
  • A lower resting HR usually means a stronger heart

• Blood pressure is assessed using a stethoscope and BP cuff
  • The person must be sitting still
  • The cuff should be positioned about 1 inch above the crease of the elbow
  • The stethoscope is applied firmly over the brachial artery
  • Inflate to about 160-180
  • Release pressure slowly (2 mm/sec.)

• Systolic pressure is the point where the pulse is first heard
• Diastolic pressure is the point where the sound disappears
• Record as sys. Over dia. Ex. = 120/80
• Various factors can affect BP and pulse rates!

I. Readiness for Exercise

• More that 1/2 the adult population reports little of no regular leisure physical activity
• The first step to beginning an exercise program is to decide that you will attempt it (Lab 6-a)
• Next, determine if you are ready to participate in a program (Lab 6-b)

II. Guidelines for Cardiorespiratory exercise prescription

• Overload- For a system to improve it must work harder than it is used to (To develop Cardiorespiratory endurance the heart muscle must be overloaded)
• Intensity- How hard a person exercises
  • Cardiorespiratory development occurs when working between 50% and 85% of maximum heart rate (MHR)
  • Training intensity can be monitored by checking the pulse
  • Determine intensity by:
    1. Determine MHR (MHR = 220 - AGE)
    2. Calculate Target Heart Rate (THR) (THR = MHR * Percentage) Percentage between 50% and 85%
    3. During exercise, if your heart rate is lower than your THR, speed up; If if is higher, slow down
  • Rate of perceived Exertion- A subjective rating in which one "self-estimates" his or her intensity

• Mode- must be aerobic to benefit the Cardiorespiratory system (Should be continuous and involve the large muscle groups of the body)
• Duration- (Based on ones rate of intensity)
  • 85% --- 20 minutes
  • 50% --- 30 minutes
• Frequency- (3 to 5 sessions per week) for weight loss 55-60 minutes of low to moderate activity

III. Specific Exercise Considerations

• Exercise during pregnancy

• Exercise can be continued with an intensity at 25%
• Exercise at least 3 times per week (Regularly)
• Pay attention to body signals
• After the first trimester, avoid lying on the back
• Use non-weight bearing activities
• Avoid balancing activities
• Get proper nourishment
• Avoid exercise in the heat

• When to exercise

• Avoid mid-day exercise on hot or humid days
• Only moderate exercise shortly after meals
• Morning exercisers stick with the program more often
• Lunch hour exercises can help with weight control
• Highly stressed people prefer evening hours

• Exercising in the cold
  • Select heat conserving clothing
  • Be aware of the wind velocity

• Exercise-related injuries
  • The four most common causes of injury:

1. High-impact activities
2. Rapid conditioning programs
3. Improper shoes or training surfaces
4. Anatomical predisposition

• Most can be prevented through a more gradual, low-impact program.
• The BEST treatment is prevention
• If an activity causes unusual discomfort, change it
• Proper treatment can avert a lengthy recovery process

• Side Stitch- A sharp pain in the side -- cause is unknown (Slow Down)
• Shin splints- A pain in the shin -- Results from:
  • A lack of conditioning
  • Exercising on hard surfaces or with poor shoes
  • Chronic overuse/fatigue
  • Faulty posture/Overweight
• Treat shin splints by: (1)reducing the cause, (2) stretching BEFORE and AFTER exercise with an ice massage, and (3) supportive taping.

IV. Leisure time (We have about 3.5 hours of free time per day -- Average)

• Factors that may motivate people to use this time for physical activity:
  • Health/Weight control
  • Fun/Social interaction
  • Competition/Mental arousal
  • Stress management/Relaxation
• Leisure time activity does NOT include a regular exercise program but does include:

• walking/hiking
• gardening/yard work
• occupational work/chores
• moderate sports (tennis, table tennis, badminton, golf)

V. Getting Started with an exercise program

• The first step is to determine your exercise prescription
• Then start (AND STICK TO) a lifetime exercise program
• Suggestions:
  • Select an aerobic activity that you enjoy
  • Use different activities
  • Set a regular time for exercise
  • Use proper clothing, equipment, and procedures
  • Exercise with a friend and set goals
  • Keep records and conduct assessments
• For fitness benefits the exercise program must be REGULAR and for a LIFETIME!
• The beneficial effects of training may be lost twice as fast as they are gained
• Strength can be maintained with one maximal training session per week
• Flexibility can be maintained with two or three sessions per week

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