PE ACUTE RESPONSES

37 cards·by phoebebrettell

Study this deck

In response to exercise, the respiratory system is responsible for...

the delivery of oxygen and removal of waste products

Ventilation

how much air is breathed in or out in one minute

Tidal Volume

how much air is inspired or expired in one breath

Respiratory Rate

the number of breaths taken in one minute

Plateau

when the body is able to supply sufficient oxygen to meet the oxygen demands of the exercise

What occurs at submaximal intensities (Respiratory)?

ventilation increases rapidly at the start of the exercise before reaching a steady state

Venous return of blood to the heart is assisted by:

muscle contractions compressing veins during an active recovery

What is meant by acute physiological responses to exercise?

the body needs to make a number of changes to accomodate the energy requirements of an activity

Acute responses...

are the initial responses to exercise of the cardiovascular, respiratory, muscular systems

Diffusion

the movement of molecules from an area of higher concentration to one of lower concentration

What is the main focus for cardiovascular responses to exercise?

getting more blood to the working muscles and to speed up the removal of carbon dioxide, waste products

Cardiac output

the amount of blood pumped out of the heart in one minute

Stroke volume

the amount of blood ejected by the left ventricle per beat

Heart rate

the number of heart beats per minute

When will heart rate stop increasing during exercise?

when oxygen demands are met

Systolic blood pressure

pressure in the arteries following contraction of ventricles as blood is pumped out of the heart

Diastolic blood pressure

pressure in the arteries when the heart relaxes and ventricles fill with blood

Venous return

the amount of deoxygenated blood returning to the heart

Mechanism 1: Venous return

the muscle pump: when muscles contract, the veins are squashed together and the blood is then forced towards the heart

Mechanism 2: The respiratory pump

breathing changes pressure in veins (thorax, abdomen) and pushed blood back to the right atrium

Mechanism 3: Venoconstriction

constriction of veins forces blood back to the heart

Blood volume

decreases during exercise

Factors influencing blood volume

Intensity, environmental factors (temperature, level of hydration of the individual)

Redistribution of blood flow

during exercise, blood flow redirected away from the spleen, kidneys, gastrointestinal tract and inactive muscles to the working muscles

Vasoconstriction (redistribution of blood flow)

occurs in the arterioles supplying the inactive areas of the body and is a decrease in the diameter of a blood vessel

Vasodilation (redistribution of blood flow)

Occurs in arterioles supplying the working muscles and is an increase in the diameter of the blood vessel

What does blood flow to the brain do?

increases to the brain in exercise such as dynamic leg exercises but remains stable in static exercise

What does blood flow to the skin do?

assists in the regulation of body temperature through heat exchange within the environment

a-vo2 diff

the difference between the amount of oxygen in blood in arteries compared with the veins

"All or nothing" principle

states that a motor unit will contract maximally or not at all depending on the strength of the stimulus

Increased blood flow (muscular response)

during exercise, blood is directed away from non-essential organs to the working muscles

Motor unit recruitment

CNS sends messages to the muscles to control muscular contractions

What's the immediate source of energy for all muscular contractions?

Adenosine triphosphate (ATP)

Where is lactate released from?

the muscle due to the anaerobic production of ATP

What happens to lactate in submaximal exercise?

there is a sharp increase in lactate- until oxygen consumption can increase to meet the energy demands of the muscle

Lactate Inflection Point (LIP)

the exercise intensity beyond which lactate production exceeds removal

How does the body respond to body temp changes during exercise?

by stimulating the sweat glands in the skin to produce sweat