physiology topic A

aerobic

with oxygen, uses oxygen durin energy production. aerobic exercise is performed at moderate level over long period.

anaerobic

without oxygen, relies on energy sources stored in muscle which do not rely on oxygen. anaerobic exercise is performed at high level over a short period.

calcium

mineral that is essential for bone growth, found in a wide range of foods.

what does long term exercise do to the skeleton

slows the rate of skeletal aging, have an active lifestyle, greater bone density. weight bearing exercises are particularly beneficial.

what type of tissue is bone, and why

dynamic tissue because it is constantly being reshaped.

osteablast

specialised bone cells that build new bone tissue

osteoclasts

large nucleatid cells that destroybone cells, reabsorb calcium and play a major role in bone remodelling.

During midlife, osteoblast and osteoclast activity is…….

balanced

as the body ages, osteoclast activity…..

increases, so a greater amount of bone tissue is broken down, releasing calcium and other minerals into the bloodstream.

osteocytes

they are mature osteoblasts that get trapped in the bone matrix.the cells control bone resorption and formation by directing osteoclasts to areas of bone that need remodelling.

synoial fluid

thick, straw coloured liquid that is a lubricant. mainly found in the cavities of synovial joints.

what does exercise do to the amount and viscosity of synovial fluid

exercise increases the amount of synovial fluid, decreasing the viscosity. This keeps the joints healthy and stops the cartilage from drying out.

what happens when the amount of synovial fluid increases

increased range of movement, reduced friction within the joint, increased nourishment of cartilage and overall better performance.

what does high intensity cardiovascular exercise do to the cardiac muscle.

improve the strength of the cardiac muscle

what does trength and conditioning do to muscle

decrease sensitivity to muscles soreness post-workout.

cardiac muscle

muscle tissue only found in the heart.

how many muscle fibres are recruited during maximal exercise and why.

only a fraction of muscle fibres are recruited at any one time to avoid muscle damage and injury.

maximal exercise

level of training intensity when an athlete approaches their maximal heart rate and peforms exercise to an increasingly anaerobic level

how do you callculate maximal heart rate

220 - your age

example- 220-17=203

when training for muscle endurance what fibres will be recruited and what will the affect be

type 1 fibres will be recruited creating a greater type 1 : type 2a : type 2x ratio. resulting in greater endurance capacity, but decrease strength.

when training for muscle strength what fibres will be recruited.

type 2a and type 2x fibres will be recruited

cardiac output

amount of blood the heart pumps through the circulatory system in a minute

blood flow is never……

evenly distributed. the body sends blood to where it is needed.

vasoconstriction

reduction in the diameter of a blood vessel,rstricting the amount of blood that can pass through

vasodilation

expansion in the diameter of a blood vessel, increasing the amount of blood that can pass through.

at rest how much blood goes to the muscles and the organs

20% muscles and 80% organs

during exercise how much blood goes to the muscles and the organs

80% muscles and 20% organs

when are micro-tears produced

during exercise when the muscle fibres contract and relax constantly against each other.

when you rest how does your body heal micro-tears and what does it cause

after activity, your body uses proteins to fill in the tears resulting in extra strength and an increase in muscle size.

whwy does your body temperature rise when exercising

as the muscle warms up, blood circulating through the muscle is also warmed.

when exercise intensity increases what happens to crbon dioxide concentration

increase in crabon dioxide concentration.

how does our body combat increased carbon dioxide concentration

increase breathing rate, to expel more carbon dioxide

what does physicalexercise do to oxygen consumption levels

increases them

when oxygen consumption increases, ………

volume of carbon dioxide produced increases

what stimulates the respiratory centre to increase breathing rate

decreased blood oxygen and increased blood carbon dioxide concentration.

anticipatroy rise

a minor increase in breathing rate prior to exercise.

when exercise begins what happens to the breathing rate

an immediate greater increase to breathing rate

medulla house - CCC

cardiac control centre

medulla house - RCC

respiratory control centre

what happens to breathing rate after several minutes of aerobic exercise

breathing rate increases at a lower rate, levelling off until exercise ends

during maximal exercise what happens to the breathing rate

continues to increase until exhaustion.

when exercising, is inspiration an active or passive process

active

when exercising, is expiration an active or passive process.

active

during inspiration when exercising what muscles are involved and what do they do

diaphragm and intercostal muscles contract. sternocleidomastoid, scalene and pectorallis minor contract.

what movement occurs during inspiration when exercising

ribs and sternum move up and out more than at rest and the diaphragm flattens with more force than at rest.

what happens to the thoracic cavity volume during inspiration when exercising

increases more then when at rest.

what happens to the lung air pressure during inspiration when exercising

decrease more then when at rest

what happens to the diffesion gradient during inspiration when exercising

a steeper diffusion gradient is created then when at rest.

what happens to the air when inspiring during exercise

more air moves in then at rest

during expiriration when exercising what muscles are involved and what do they do

diaphragm and external intercostals relax. rectus abdominis and interal intercostals and obliques contract

what movement occurs when expiring during exercise

ribs and sternum move down and in more then at rest and the diaphragm relaxes quicker then at rest.

what happens to the thoracic cavity volume when expiring during exercising

decreases more then at rest

what happens to the lung air pressure when expiring during exercise

increases more then at rest.

what happens to the air when expiring during exercise

more air rushes out then at rest.

tidal volume

amount of air ventilated in or out of the lungs in one breath.

what happens to tidal volume during exercise and why

increases dramatically due to the body's demnd for more oxygen and to offload increased levels of carbon dioxide.

alveolar ventilation

tidalvolume minus any dead space (air that remains in the trachea, bronchi, etc.)

at low to moderate exercise what happens to the tidal volume and breathing rate

they increase proportionally.

at high intensity exercise, what happens to the tidal volume and breathing rate

tidl volume reaches a peak and any further increase in minute volume requires an increase in breathing rate.

what does the oxygen dissociation curve show

the relationship between the % of oxygen saturation of the blood and the partial pressure of oxygen

partial presure

pressure applied by a single gas in a mixture of gases.

haemoglobin

oxygen transporting component of red blood cells

lactate

product of lactic acid, hich occurs in the blood

blood ph

measures the acidity or alkalinity of a solution -blood-

when exercising how does increased temp and low blood ph affect the oxygen-haemoglobin dissociation curve

affects the oxygen-haemoglobin curve in a way that more oxygen can be unloaded to supply the active muscles.

how does prolonged high intensity exercise affect lactate

large amounts of lactate enter the blood from the active muscles.

what ph is blood normally

7.4 ph

cardiac cycle

the sequence of events that take place during single heartbeat

systole

contraction phase of the heartbeat

diastole

relaxation phase of the acrdiac cycle.

what happens to the heart rate before exercise

an anticipatory rise

what causes the anticipatory rise in heart rate

neurotransmitters like adrenaline and noradrenaline which are released from the brain.

neurotransmitters

chemicals used to carry signals or information between neurons and cells.

why does the heart need t increase before exercise

increases blood flow, which supplies poxygen and nutrients to the muscles that are about to be worked.

cardiac output

volume of blood pumped out of the heart in one minute

stroke volume

volume of blood pumped out of the hearts left ventricle per beat

what is heart rate controlled by

sinoatrial node (SAN)

sympathetic nerve

speeds up the heart rate. synapses at the end of this nerve secrete noradrenaaline

parasympathetic nerve

slows down the heart rate.synapses at the end of this nerve secrete acetylcholine

when does stroke volume reach its peak

during submaximal exercise and it does not increase during maximal exercise.

why does stroke volume not increase during maximal exercise

the left ventricle is already at capacity, so the body tolerates maximal exercise for as long as possible by increasing the heart rate and maintaining stroke volume.

what are the benefits of increased cardiac output

transport more blood to working muscles, which delivers more oxygen

how does heart rate and stroke volume adapt after long term exercise

resting heart rate decreases and stroke volume increases

what does starlings law state

stroke volume increases in responce to an increase in blood filling the heart.

what does an increase of blood in the heart cause

stretching of the ventricular walls which causes the cardiac muscle to contract more forcefully.

blood pressure=

cardiac output x resistance

what occurs during steady state exercise

dilation of the blood vessels in active muscles increases the vascular rea for blood to flow.

systolic pressure

pressure exerted on the walls of arteries when the heart contracts and blood is ejected from the left ventricle

how does muscle strength training affect blood pressure and why

significantly raise blood pressure because blood being forced through skeletal muscles is beng subjected to increased intra-muscular pressure.

diastolic pressure

pressure exerted on the walls of the arteries when the heart relaxes and fills with blood.

what is the optimal adult blod pressure at rest

120/80 mmHg

what varies blood pressure

age, gender, race, activity level

prehypertension

systolic reading of 120 to 139 or diastolic pressure of 80 to 89

hypertensive

140/90

what happens to systolic and diastolic pressure during exercise

systolic blood pressure will rise progressively and diastolic will stay the same or reduce slightly

what causes blood ph to decrease during exercise

carbon dioxide and lactic acid

what happens t diffusion rates during exercise and why

diffusion rates increase to allowmore oxygen movement from capillaries to muscles. And carbon dioxide diffuses into blood for exhalation

arteriovenous oxygen difference

difference in oxygen content between arterial blood and venous blood

arterial blood

bright red in colour due to high concentrations of oxygen

venous blood

darker red in colour due to high cencentrations of carbon dioxide.