Key Terms Flashcards
Anticipatory Rise
The release of adrenaline via the sympathetic nervous system prior to exercise.
Arteriole
Small blood vessel which extends from an artery to meet the capillaries
Atrial and ventricular repolarisation
Occurs during a brief time period following depolarisation and describes the electrical impulse returning to a baseline value.
Atrial depolarisation
The effect that the SA node has on the atria, causing them to contract by providing an electrical stimulus across them.
Baroreceptors
Sensors detecting changes in blood pressure
Cardiac output
The volume of blood ejected by the heart per minute
Cardiovascular drift
The ‘drift’ effect of cardiovascular responses to sustained steady-state exercise, despite exercise intensity not increasing.
Chemical regulation
The control of physiological processes via the chemoreceptors
Chemoreceptors
Sensors detecting chemical changes within the blood
Heart rate
The number of times the heart beats per minute
Medulla oblongata
An extension of the spinal cord found in the skull that contains control centres for the heart and lungs.
Myogenic
Originating in muscle tissues, rather than through neural impulse. The heart is myogenic, as it creates its own impulses intrinsically.
Neural control
The control of physiological processes via the sympathetic and parasympathetic nervous systems
Oxyhaemoglobin
A combination of oxygen and haemoglobin
Pre-capillary sphincter
Smooth muscle that regulates capillary blood flow
Proprioceptors
Sensors that detect changes in body position through changes in muscle length, tension and joint angles.
Stroke volume
The amount of blood ejected from the heart per beat
Vascular shunt mechanism
How the vascular system shunts and redistributes blood towards the exercising muscles via vasodilation and vasoconstriction
Vasoconstriction
The narrowing of arteries to restrict blood flow
Vasodilation
The widening of arteries to increase blood flow
Vasomotor centre
Regulates blood flow by stimulating the sympathetic system, causing vasoconstriction or vasodilation.
Breathing frequency
The number of breaths per minute
Exercise post-exercise oxygen consumption (EPOC)
The increase volume of oxygen consumed following exercise
Expiration
The process of breathing out
Expiratory reserve volume
The extra air that can be exhaled after normal exhalation
Inspiration
The process of breathing in
Inspiratory reserve volume
The extra air that can be inhaled after normal inhalation
Minute ventilation
The volume of air inspired or expired per minute
Parasympathetic nervous system
One half of the automatic nervous system that stimulates body systems rest or relax
Residual volume
Amount of air left in the lungs prior to forced exhalation
Sympathetic nervous system
One half of the automatic nervous system that stimulates or activates the fight or flight of body systems
Tidal volume
The volume of air displaced from the lungs during steady-state inspiration and expiration
Action potential
An electrical impulse that stimulates the muscle fibres
All or none law
A muscle fibre has to either fully contract or not contract at all; there is no in-between level of contraction.
All or nothing.
Fast glycolytic muscle fibre
Type IIx muscle fibre, characterised by features such as high force production and high glycolytic capacity.
Fast oxidative glycolytic muscle fibre
Type IIa muscle fibre, characterised by features such as high oxidative capacity and a fast contraction time.
Motor neuron
A nerve cell joining muscle fibres at a neuromuscular junction
Neurotransmitter
Chemicals which stimulate the action potentials to travel across synapses to another neuron
Spatial summation
When an increasing amount of motor units are recruited
Tetanic contraction
The stimulation of the muscle occurs too rapidly to allow any relaxation
Wave summation
Increasing the strength of muscular contraction by increasing the frequency of impulses.
Agonist
The muscle that is the primary instigator of a joint movement
Antagonist
The muscle that opposes the motion of the agonist
Concentric
A muscular contraction that involves the muscle becoming shorter
Eccentric
A muscular contraction that involves the muscle lengthening
Fixator
The muscle that stabilises the joint during movement, aiding the efficiency of the agonist muscle
Isometric
A muscular contraction that involves no change in muscle length
Isotonic
Describes a change in muscular length as it undergoes contraction.
Slow oxidative muscle fibre
Type 1 muscle fibre, characterised by features such as a slow contraction time and low force production.
Adenosine triphosphate (ATP)
The key source of energy in the body
ATP resynthesis
The production of ATP through the use of energy, ADP and P
Blood lactate
A substance that pyruvate is converted into in the absence of oxygen
Energy continuum
How and when each of the three energy systems becomes predominant when producing the energy needed for exercise
Enzyme
A catalyst that causes a biochemical reaction (breakdown of substances)
EPOC
The increased level of oxygen consumption following exercise
Fast component of EPOC
Involves the replenishment of the blood supply and muscle oxygen stores, and resynthesis of ATP
Glucose
A simple form of sugar easily broken down for energy in the body
Glycogen
Chains of glucose that the body uses as energy (but takes longer to break down)
Indirect calorimetry
A method of measurement to determine the volume of oxygen consumes, and carbon dioxide produced, to provide a value for energy expenditure
Intensity
How hard a body is working
OBLA
An increase in blood lactate above 4mmol/L
VO2 max
The maximum amount of oxygen an individual can utilise in the body during maximal intensity exercise
Respiratory exchange ratio
The difference between the amount of oxygen utilised by the body and the amount of carbon dioxide produced when exercising.
Slow component of EPOC
Involves elevated circulation, ventilation and body temperature.
