Exercise Physiology Exam #3

cardiac cycle

The period that includes all events between two consecutive heartbeats.

Cardiac Output

Volume of blood pumped by heart per minute.

diastolic blood pressure

lowest arterial pressure, resulting from ventricular diastole

ejection fraction

The fraction of blood pumped out of the left ventricle with each contraction, determined by dividing stroke volume by end-diastolic volume and expressed as a percentage.

Electrocardiogram (ECG)

A recording of the electrical activity of the heart

End Diastolic Volume (EDV)

volume of blood remaining in the left ventricle at the end of diastole, just after contraction

End Systolic Volume (ESV)

Amount of blood remaining in each ventricle at the end of systole (contraction).

functional sympatholysis

the process in which vasoactive molecules released from active skeletal muscle inhibit sympathetic vasoconstriction in order to increase blood flow to exercising muscle

stroke volume

amount of blood ejected from left ventricle during contraction; the difference between the EDV and ESV

systolic blood pressure

greatest arterial blood pressure, resulting from systole

primary functions of blood

-Transportation= transport oxygen, nutrients, hormones, waste products throughout the body system

-Regulation= fluid, electrolyte, acid-base balance

-Protection= combat infection & stop bleeding

Muscle Pump Mechanism

Muscular contractions compress the veins, squeezing blood back towards the heart

Respiratory pump mechanism

pressure changes occur in the thoracic and abdominal cavities during inspiration and expiration. This compresses veins and assists blood return to the heart

Vasoconstriction mechanism

sympathetic nervous system stimulates smooth muscle in the walls of veins to contract, narrowing them to increase pressure, propel blood back to the heart

Boyle's Law

A principle that describes the relationship between the pressure and volume of a gas at constant temperature

Dalton's Law

The total pressure of a mixture of gases is the sum of the individual pressures (Ptotal=P1+P2+P3...)

Expiration

breathing out (exhalation)

Fick's Law

law stating that the net diffusion rate of a gas across a fluid membrane is proportional to the difference in partial pressure, proportional to the area of the membrane, and inversely proportional to the thickness of the membrane

Henry's Law

the solubility of a gas in a liquid is directly proportional to the partial pressure of that gas on the surface of the liquid

inspiration

breathing in (inhalation)

residual volume

The volume of air remaining in lungs after maximum exhalation.

tidal volume

amount of air inhaled or exhaled with each breath under resting conditions

total lung capacity

the sum of vital capacity and residual volume

vital capacity

The total volume of air that can be exhaled after maximal inhalation.

pulmonary diffusion

exchange of gas molecules (oxygen and carbon dioxide) from areas of high concentration to areas of low concentration

pulmonary ventilation

movement of air in and out of the lungs

hemoglobin concentration

The measure of the concentration of hemoglobin in a given volume of packed red blood cells

arterial oxygen saturation

-SaO2, the amount of oxygen bound to hemoglobin

afterload

Pressure ventricles must overcome to eject blood into the aorta

cardiovascular drift

Upward drift of heart rate during sustained steady-state activity associated with an increase in body temperature

dyspnea

difficult or labored breathing

maximal heart rate

the highest heart rate you can achieve during maximal exercise

preload

passive stretch applied to the ventricular myocardium at the end of diastole

resting heart rate

the number of times your heart beats per minute when you are not active

steady state heart rate

a heart rate that is maintained constant at submaximal levels of exercise when the rate of work is held constant

Valsalva maneuver

forceful exhalation against a closed glottis, which increases intrathoracic pressure and thus interferes with venous blood return to the heart

ventilatory threshold

The point during graded exercise in which ventilation increases disproportionately to oxygen uptake, signifying a switch from predominately aerobic energy production to anaerobic energy production.

skeletal muscle pump

one way venous valves prevent blood from flowing backward during muscle relaxation, ensuring constant upward flow

Frank-Starling Mechanism

A mechanism by which the stroke volume of the heart is increased by increasing the venous return of the heart (thus stretching the ventricular muscle).

frank-starling mechanism during exercise

increased preload stretches ventricles, which then contracts more forcefully, leading to higher stroke volume

blood pressure response to exercise

increase in systolic BP, little or no change in diastolic BP

cause of postexercise hypotension

persisted vasodilation, blood pooling, histamine activation, dehydration/heat

1RM

Maximum amount of weight a group of muscles can lift at one time

continuous training

training at a moderate to high intensity without stopping to rest

Fartlek training

combination of continuous and interval training and stresses both the aerobic and anaerobic energy systems

interval training

repeated, brief, fast-paced exercise bouts with short rest intervals between bouts

Long, Slow Distance (LSD) Training

endurance training involving long, slow distances; around 50-75% of HRmax

plyometrics

dynamic-action resistance training based on the theory that the use of the stretch reflex during jumping will add more motor units

strength

the amount of force your muscles can produce; allows the muscles to overcome resistance

power

the rate at which work is done; crucial for explosive, sport specific movements

endurance

ability of a muscle to perform repeated contractions or hold a contraction against resistance over a prolonged period

importance of endurance

allows the body to maintain proper form and contractions for a long period of time without fatigue

aerobic power

defines cardiovascular fitness and endurance capacity

anaerobic power

rate at which the body can meet demand for short-term intense activity; essential for explosive processes

factors in a resistance training program

SAID principle, exercise selection/order, frequency, intensity/volume, progressive overload, rest periods, periodization

principle of individuality

the theory that any training program must consider the specific needs and abilities of the individual for whom it is designed

principle of specificity

A rule that states that specific types of exercise improve specific parts of fitness or specific muscles.

principle of progressive overload

the theory that, to maximize the benefits of a training program, the training stimulus must be progressively increased as the body adapts to the current stimulus

Principle of Reversibility

the theory that a training program must include a maintenance plan to ensure that the gains from training are not lost

Principle of Variation

systematically changes one or more variables to keep training challenging

atrophy

the wasting away of a body organ or tissue

chronic hypertrophy

the increase in muscle size after long-term resistance training

fiber hyperplasia

an increase in the number of muscle fibers

fiber hypertrophy

an increase in the size of existing individual muscle fibers

sarcopenia

the loss of muscle mass, strength, and function that comes with aging

transient hypertrophy

the increase in muscle size that develops during and immediately following a single exercise bout

athletes heart

a nonpathological enlarged heart, often found in endurance athletes, that results primarily from left ventricular hypertrophy in response to training

Cardiac Hypertrophy

enlargement of the heart by increases in muscle wall thickness or chamber size or both

Muscular Endurance

the ability of your muscles to perform physical tasks over a period of time without tiring

cardiovascular endurance

the ability of the heart, lungs and blood vessels to deliver oxygen to your body tissues

response to muscle immobilization

reduced protein synthesis; decease in size and nuerolgical activity; type 1 fibers affected more than type 2

benefits of resistance training

Increased endurance, strength, and power, muscular hypertrophy; Improved weight management; Improved resting metabolic rate, resting heart rate, and blood pressure; Improved coordination and athleticism; Decreased risk of injury due to strength of all soft tissues

protein intake for hypertrophy training

muscle strength: 20-25g after exercise; 1.6-1.7g/kg BW/day

high responders

those individuals within a population that show clear or exaggerated responses or adaptations to a stimulus

Low responders

those individuals within a population that show little or no response or adaptation to a stimulus

Limits of VO2 max

Age- 1-2% decrease after age 30, genetics, training status

cross training for power athletes

increase in explosiveness, muscle balance and stability, increase in CVD stamina

cross training for endurance athletes

injury prevention, mental freshness, better/faster recovery

Primary Functions of Blood

Transportation

Temperature Regulation

Acid-Base pH Balance

How is blood flow to various regions of the body controlled?

Blood flow= Change in Pressure / Radius of Arteriole, As changes in pressure drives flow the changes in arteriole radius also impact blood flow.

How does muscle blood flow incresae during exercise despite increased sympathetic nerve activity that favors vasoconstriction?

Functional Sympatholysis allows muscle to overcome vasocontriction & increase blood flow.

What is the difference betweeen systole and diastole, and d]how do they relate to SBP and DBP?

Systole: contraction phase, QRS —> T wave

SBP-Highest Pressure in artery, during systole

Diastole: relaxation phase, Twave—>Next QRS

DBP-Lowest pressure in artery, during diastole

Describe the threee important mechanisms for returning blood back to the heart when someone is exercising in an upright position.

One- way venous valves—Prevent backward flow of blood bc of gravity

Muscle Pump—muscle compress the vein

Respiratory Pump—increased breathing lower chest pressure

Explain the difference between pulmonary diffusion and pulmonary ventilation.

Pulmonary ventilation is the mechanical process of moving air in and out of the lungs (breathing), while pulmonary diffusion is the passive exchange of oxygen and carbon dioxide between the alveoli and pulmonary capillaries.

What three factors influence oxygen delivery and uptake?

Oxygen content of blood, blood flow, local conditions (pH, Temp)

What is a spirometer? Briefly describe the lung volumes measured using spirometry.

measure the volume of air an individual can inhale and exhale, as well as the speed of airflow

—Tidal volume

– Vital capacity (VC)

– Residual volume (RV)

– Total lung capacity (TLC)

What two ways is oxygen transported by the blood? Briefly describe both of these.

>98% bound to hemoglobin (Hb) in red blood cells

– O2 + Hb: oxyhemoglobin

– Hb alone: deoxyhemoglobin

• <2% dissolved in plasma

Briefly describe how carbon dioxide is carried in the blood (hint: there are three forms).