chap 6

metabolic equivalent of tasks

MET- resting oxygen uptake is estimated at 3.5 ml of oxygen per kilogram of body weight per minute

vasoconstriction and vasodilation

___ and ___ of blood vessels are the primary mechanisms for regulating regional blood flow

stroke volume x heart rate

cardiac output = ___ x ___

stroke volume

quantity of blood ejected with each beat

myoglobin

a protein that transports oxygen within the cell

anatomical dead space

air occupies areas of the respiratory passages: the nose, mouth, trachea, bronchi, and bronchioles. this area is not useful for gas exchange and is called the __

venous return

amount of blood returning to the heart

overreaching

an overtrained state can last for a brief period of time, perhaps for a few days

hyperoxic breathing

breathing oxygen-enriched gas mixtures during rest periods or following exercise

overtraining

caused by extreme levels of training frequency, volume, intensity, or a combination of these variations without sufficient rest or recovery

systolic blood pressure

estimates the pressure exerted against the arterial walls as blood is forcefully ejected during ventricular contraction and when combined with heart rate, can be used to describe the work of the heart

intensity

heart rate increases linearly with the increases in ____ during aerobic exercise

heart rate

heart's rate of pumping

detraining

if inactivity, rather than proper recovery, follows exercise, an athlete loses training adaptations and experiences ___

hyperventilation

increase in pulmonary ventilation at rest during exercise

fick equation

oxygen uptake VO2 can be calculated with ___ which expresses the relationship of cardiac output, oxygen uptake, and arteriovenous oxygen difference

physiological dead space

refers to alveoli in which poor blood flow, poor ventilation, or other problems with the alveolar surface impair gas exchange

catecholamines

regulation of stroke volume- due to the action of ____, epinephrine and norepiephrine which are hormones of the sympathetic nervous system that produce a more forceful ventricular contraction and greater systolic emptying of the heart

frank starling mechanism

related to the concept that the force of contraction is a function of the length of the fibers of the muscle wall

bradycardia

slower heart rate

50-60

stroke volume increases at the onset of exercise and continues to rise until oxygen consumption is ___ % of maximal oxygen uptake

tidal volume

the amount of air inhaled and exhaled with each breath

cardiac output

the amount of blood pumped by the heart in liters per minute and is determined by the quantity of blood ejected with each beat and the heart's rate of pumping

oxygen uptake

the amount of oxygen consumed by the body's tissues

mean arterial pressure

the average blood pressure throughout the cardiac cycle

arteriovenous oxygen difference

the difference in the oxygen content between arterial and venous blood

rate pressure product, double product

the estimate of the work of the heart is obtained according to the following equation is referred to as ___ = heart rate x systolic blood pressure

maximal oxygen uptake

the greatest amount of oxygen that can be used at the cellular level for the entire body

ejection fraction

the increase in cardiac emptying is characterized by an increase in the ___, the fraction of the end-diastolic volume ejected from the heart

diffusion

the movement of oxygen and carbon dioxide across a cell membrane and is a function of the concentration of each gas and the resulting partial pressure exerted by the molecular motion of each gas

mitochondria

the organelles in cells that are repsonsible for aerobically producing adenosine triphosphate (ATP) via oxidation of glycogen

blood doping

the practice of artificically increasing red blood cell mass as a means to improve athletic performance

ventilatory equivalent

the ratio of minute ventilation to oxygen uptake ___ and ranges between 20 and 25 L of air per liter of oxygen consumed

total peripheral resistance

the resistance of the entire systemic circulation

overtraining syndrome

the result of overtraining, or staleness

minute ventilation

the volume of air breathed per minute

end diastolic volume

the volume of blood available to be pumped by the left ventricle at the filling phase, or diastole

diastolic blood pressure

used to estimate the pressure exerted against the arterial walls when no blood is being forcefully ejected through the vessels

systole

ventricular contraction

diastole

ventricular relaxation

alveoli

with inspiration, air enters the ___, the functional unit of the pulmonary system where gas exchange occurs