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