phsiology Flashcards
body's responses to exercise when exercising you increase your body's energy use
meaning of physiology
body’s responses to exercise when exercising you increase your body’s energy
aerobic
involves the use of oxygen in energy production such as long-distance running at moderate pace
anaerobic
without oxygen (relies on energy sources stored in the muscles) includes heavy lifting, sprints rapid exercise
Muscular system responses
High intensity cardiovascular exercise can improve strength of cardiac muslce
cardiac output
the amount the heart pumps through the circulatory system in a min
vasoconstriction
reduction in the diameter of blood vessels
vasodilation
expansion in the diameter of blood vessels
blood flow to working muscles ( what is the terms where the body sends blood)
body sends blood where is needed by vasoconstriction and vasodilation
blood flow to working muscles ( what per cent of blood goes to your muscles at rest)
At rest 20 per cent of blood goes to muscles
what energy is required during exercise
all muscles require energy from fuels such as carbohydrates and fats
respiratory system responses
The more intense the exercise the greater carbon dioxide concentration in the blood to combat this your breathing increases to help expel the carbon dioxide
Anticipatory rise (key term)
a minor increase in breathing rate prior to exercise
Decreased blood oxygen
the amount of oxygen in the blood
Tidal volume
is the amount of air ventilated in or out of the lungs in one breath ( low to moderate intensity)
Alveolar ventilation ( key term
tidal volume minus dead space( air that remains in trachea, bronchi etc)
what dose tidal volume do
it increases dramatically during exercise due to the body’s demand for more oxygen or the need to offload increased levels of carbon dioxide
partial pressure (key term
pressure applied by a single gas in a mixture of gasses
Haemoglobin ( key term
oxygen transporting component of red blood cells
Lactate ( key term
product of lactic acid which occurs in blood
Blood pH ( key term
measure of acidity or alkalinity of a solution
cardiac cycle ( key term
the sequence of events( systole- during which cardiac muscle contracts and diastole during which cardiac muscle relaxes) that take place during a single heartbeat
Neurotransmitters (key term
chemicals used to carry signals or information between neurons and cells
stroke volume (key term
volume of blood pumped out of the hearts left ventricle per beat
Cardiac cycle
when the body detects an increase in exercise intensity the cardiac cycle must respond
cardiac ouput
is the volume of blood pumped out of the heart in 1 minute
stroke volume
is the amount of blood pumped by the left ventricle in one contraction
stroke volume during exercise
during exercise stroke volume increases progressively and gradually levels off at a high level until exercise has ended
Heart rate
heart rate changes to the body’s needs at rest a normal adults heart beats approximately 75 times per minute
what is heart rate controlled by
SAN( sinoatrial node
How SAN works
the heart rate goes up or down when SAN receives information via nerves that link the SAN with the cardiovascular centre in the brain
the sympathetic nerve
speeds of the heart
parasympathetic nerve
slows down the heart
Starlings law
is a theory which states that stroke volume increases in response to an increase in blood volume filing the heart stroke volume my also increase due to stronger contractions in the cardiac muscles during exercise
systolic pressure (key term
pressure exerted in the arteries when the heart contracts
arterial blood (key term
bright red in colour due to high concentrations
venous blood (key term
darker red than arterial blood due to high concentrations of carbon dioxide
diffusion rate
during exercise diffusion rates increase to allow more movement from the capillaries to the working muscles while carbon dioxide is exchanged into the blood
Arteriovenous oxygen difference ( a -VO2 diff)
is the difference in the oxygen content between arterial and venous blood
Arteriovenous oxygen difference ( a -VO2 diff) when exercising
exercise leads to an increase in this difference because, as exercise intensifies the working tissue demands more oxygen from the arterial blood so the oxygen content of venous blood decreases
neuromuscular system responses
neuromuscular refers to both the nervous system and muscular system
what is the two nerves ( neuromuscular system
sensory neurons and motor neurons
what is sensory neurons
carry information from our extremises(the skin) to the central nervous system(the brain and spinal cord)
what is motor neurons
carry information from our central nervous system to our muscles
Nervous control of muscaulr contarction
muscles contract when stimulated by nerves there is three basic types of contraction can occur during exercise
3 types of contraction
isotonic contraction, isometric contraction and isokinetic
isotonic contraction
the muscle shortens as it develops tension
isometric contraction
the muscle develops tension but does not change length.
Isokinetic contraction
the muscle contracts to its maximum at a constant speed over the full range of movement
muscle contraction
Muscles contract and relax due to muscle filaments moving backwards and forwards across each other. What causes these backwards and forwards movements to occur is the
actions of specialised nerve cells called motor units working at a neuromuscular junction.
Neuromuscular junction
a neuromuscular junction is the site at which a motor
neuron communicates with a muscle fibre using nerve impulses.
what is a motor unit made up of
made up from a motor neuron and all the associated muscle fibres
how motor works
Motor units work together to coordinate contractions of
a single skeletal muscle, although the number of fibres in each unit varies based
on the muscle size and role
motor units during exercise
During low-intensity exercise, Type I motor units are
recruited. As the intensity is increased Type IIa motor units are recruited until the
intensity is enough to recruit Type IIx motor units
Proprioceptors (key term
sensory
receptors found in muscle
tissue, tendons and joints
which tell the brain about the
physical state and position of
a muscle or joint
