Principles of Aerobic Exercise

any bodily movement produced by the contraction of skeletal muscles that result in a substantial increase over time of energy expenditure
physical activity or exercise?

physical activity
according to ACSM and CDC

planned and structured physical activity designed to improve or maintain physical fitness
physical activity or exercise?

exercise

physical activity:
- walking/running
- biking
- running
- swimming
- stair climbing
- training with weights
- yardwork
- shoveling snow
- heavy cleaning
- dancing
- sports

...

true or false: individuals can improve their general fitness status by participating in a variety of physical activities, including exercise

true
fitness levels can be described on a continuum from poor to superior based on energy expenditure during a bout of physical work

what is a general term used to describe the ability to perform physical work?

fitness

fitness requires what components? (3)

- cardiorespiratory functioning
- muscular strength and endurance
- musculoskeletal flexibility

true or false: body composition is also a consideration when describing fitness

true

what is a measure of the body's capacity to use oxygen?

maximum oxygen consumption (VO2max)
- the maximum amount of oxygen consumed per minute when the individual has reached maximum effort
- expressed as mL/kg/min

VO2max is quantified in what equation?

Fick equation

true or false: VO2max is a linear relationship with energy expenditure

true

slide 8: VO2max

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true or false: VO2max indirectly measures your ability to do work

true

VO2 = ?

(HR x SV) x (a - v O2 diff)
OR
cardiac output x oxygen delivery

factors affecting VO2 max:
- HR (220-age)
- drugs
- SA node dysfunction
- SV (volume of venous blood returned to the heart, ventricular distensibility, ventricular contractility, aortic/pulmonary pressures)

...

the ability of the cardiorespiratory system to deliver the oxygen to the contracting muscles
which part of the fick equation?

HR x SV (cardiac output)

the ability of the muscles to utilize the oxygen delivered to it by the cardiorespiratory system
which part of the fick equation?

a - v O2 diff

- the amount of blood pumped from the heart in 1 min
- represents oxygen delivery
which part of the fick equation?

cardiac output (HR x SV)

- the difference in the amount of oxygen in arterial blood compared to the venous blood
- represents the amount of blood actually extracted by the tissues
which part of the fick equation?

a - v O2 difference

Q x (a - v O2 difference) = ?

VO2 max
Q = cardiac output (HR x SV)

what is a measure of fitness that refers to the ability to work for a prolonged period of time and the ability to resist fatigue?

endurance

what type of endurance refers to the ability to perform large muscle dynamic exercises for long periods of time?

cardiovascular endurance
such as walking, swimming, or biking

isolated muscle group
what type of endurance?

muscular endurance

a person lifting a 150-pound barbell during one maximal muscular effort demonstrates muscular strength or endurance?

muscular strength

a person lifting a 75-pound barbell a dozen times demonstrates muscular strength or endurance?

muscular endurance

what is the augmentation of the energy utilization of the muscle by means of an exercise program?

aerobic exercise training (or conditioning)
requires sufficient frequency, intensity, and duration

true or false: aerobic exercise training produces ADAPTATIONS reflected in the individual's endurance

true

true or false: aerobic exercise training is dependent on the SPECIFICITY PRINCIPLE

true

the individual improves on the exercise task used for training and may not improve in other tasks
this is called?

specificity principle
for example, biking may enhance one's performance in biking events, but not improve one's performance in swimming

cardiovascular and muscular ______ results in increased efficiency, which can be measured in as little as 10 to 12 weeks

adaptation
improved performance, i.e., the same amount of work can be performed but at a lower physiologic cost

adaptation is dependent on the person's ability to change and the ______ ______ threshold

training stimulus (the stimulus that elicits a training response)

- occurs with prolonged bed rest
- frequently seen in patients who have extended acute illnesses or long-term chronic conditions
- also seen in individuals who are sedentary because of lifestyle or age

deconditioning

deconditioning effects associated with bed rest:
- < muscle mass
- < strength
- < cardiovascular function
- < total blood volume
- < plasma volume
- < heart volume
- < orthostatic tolerance
- < exercise tolerance
- < bone mineral density

...

aerobic, slow twitch, resistant to fatigue
skeletal muscle type?

type I
- long distance runners
- tend to atrophy first
- most ADLs tend to use more type I fibers

aerobic, fast twitch, intermediate resistance to fatigue
skeletal muscle type?

type IIa

anaerobic, fast twitch, low resistance to fatigue
skeletal muscle type?

type IIb

ATP-PC system (phophocreatine) is used as fuel for what type of skeletal muscle?

type II fast twitch fibers

what is used as fuel for short, quick bursts of intense exercise?

ATP-PC system (phosphocreatine) - anaerobic

what is used as fuel for moderate intensity and short duration exercise?

glycolytic system (glucose) - anaerobic

what is used as fuel for endurance training?

aerobic system (glycogen, fats, protein) - aerobic

timing for the aerobic system?

after the second minute of exercise

timing for the ATP-PC system?

first 30 seconds of exercise

timing for the glycolytic system?

30th to 90th second of exercise

what fuel system(s) are anaerobic?

- ATP-PC (phosphocreatine)
- glycolytic (glucose)

what fuel system utilizes glucose free floating in the bloodstream broken down by glycolysis without O2?

glycolytic system

what fuel system(s) are aerobic?

aerobic system (glycogen, fats, protein)
beyond 90sec/2min requires oxidation process: glycolysis produces pyruvate which is then broken down in the mitochondria further and enters the Krebs cycle

bursts of intense activity lasting only seconds develop?

muscle strength and stronger tendons and ligaments
ATP is supplied by the phosphagen system

intense activity lasting 1 to 2 minutes repeated after 4 minutes of rest or mild exercise enhances?

anaerobic power
ATP is supplied by the phosphagen and anaerobic glycolytic system.

activity with large muscles, which is less than maximum intensity for 3 to 5 minutes repeated after rest or mild exercise of similar duration, may develop?

aerobic power and endurance capabilities
ATP is supplied by the phosphagen, anaerobic glycolytic, and aerobic systems

activity of submaximum intensity lasting 20 to 30 minutes or more taxes a high percentage of the aerobic system and develops?

endurance

kilocalories (kcals) and metabolic equivalents (METs) are units used to quantify?

energy expenditure

the amount of heat necessary to raise 1 kilogram of water 1 degree C
unit?

kilocalorie (kcal)
five kcal = 1 liter of O2

five kcal = ?

1 liter of O2

the oxygen consumed per kilogram body weight per minute
unit?

MET (metabolic equivalent)
1 MET = 3.5 mL/kg/min

1 MET = ?

3.5 mL/kg/min

Note: activities are classified as light, moderate, or heavy according to the energy expended or the oxygen consumed while accomplishing them

...

______ work for the average male (65 kg) requires 2.0 to 4.9 kcal/min, or 6.1 to 15.2 mL O2/kg per minute, or 1.6 to 3.9 METs. strolling 1.6 km/hr, or 1.0 mph, is considered light work

light

______ work for the average male (65 kg) requires 7.5 to 9.9 kcal/min, or 23.0 to 30.6 mL O2/kg per minute, or 6.0 to 7.9 METs. jogging 8.0 km/hr, or 5.0 mph, requires 25 to 28 mL O2/kg per minute and is considered heavy work. the energy expended is equiv

heavy

true or false: the energy expenditure necessary for most industrial jobs requires more than three times the energy expenditure at rest

true
energy expenditure of certain physical activities can vary, depending on factors such as skill, pace, and fitness level

cardiovascular response to aerobic exercise:
- exercise pressor response
- cardiac effects
- peripheral effects

initial SNS response (pressor response):
- increase HR
- vasodilation to working muscles, heart, and lungs
- vasconstriction to non-working organ (GI, kidney, liver, spleen) resulting in increased blood delivery to working muscles and increased venous ret

respiratory response to aerobic exercise:
- respiratory changes
- minute ventilation
- alveolar ventilation

- RR increases and minute volume increase (total amount of air a person breathes in a minute RR x tidal volume)
- breathing more rapidly and taking in greater quantities of oxygen with each breath
- alveolar ventilation (amount of O2 reaching the alveoli)

- increased blood flow
- increased oxygen extraction
effect of what on the fick equation?

aerobic exercise

what effect does aerobic exercise have on CO (fick equation)?

increased blood flow
CO = HR x SV

what effect does aerobic exercise have on (a - v O2 diff)?

increased oxygen extraction