1.1d environmental effects on body systems

Question 1

barometric pressure

Answer 1

pressure exerted by the earth’s atmosphere at any given point

Question 2

diffusion

Answer 2

the movement of gas across membrane down gradient

Question 3

thermoregulation

Answer 3

the process of maintaining internal core temp

Question 4

altitude

Answer 4

the height or elevation of an area above sea level

has an effect over 1500m

Question 5

dehydration

Answer 5

loss of water in body tissues, largely caused by sweating

Question 6

humidity

Answer 6

amount of water vapour in atmospheric air

Question 7

partial pressure

Answer 7

pressure exerted by an individual gas held in a mixture of gases

Question 8

vascular drift

Answer 8

upward drift in heart rate during sustained, steady-state activity associated with an increase in body temp

Question 9

hyperthermia

Answer 9

significantly raised core body temp

Question 10

erythropoietin

Answer 10

naturally produced hormone responsible for production of red blood cells

Question 11

thermoreceptors

Answer 11

sensory receptors that sense a change in temp and relay info to the brain

Question 12

acclimatisation

Answer 12

process of gradual adaptation to a change in environment, eg lower po2 at altitude

Question 13

what is oxygen like at altitude

Answer 13

-lower partial pressure of oxygen THAN AT SEA LEVEL

-decreased rate of oxygen diffusion

Question 14

what effect does altitude have on the respiratory and cv system

Answer 14

-decreased rate of oxygen diffusion

-reduced haemoglobin saturation

-poor transport of oxygen for aerobic resp

Question 15

what result does the effect of altitude on cv and r have

Answer 15

-inc bf

-blood volume decreases as plasma decrease

-sv decreases - inc hr to maintain q

-max q, sv and hr decrease during max intensity

Question 16

what effect does altitude have on vo2 max and aerobic capacity

Answer 16

both reduced and impact intensity and duration of performance.

Question 17

how much does vo2 max drop every 1000m above 1500m?

Answer 17

8-11%

Question 18

what effect does altitude have on anaerobic energy systems

Answer 18

greater demand leading to increased lactic acid production at sub max
-early fatigue

Question 19

when should a performer start to acclimatise

Answer 19

low altitude 1000-2000m
-3-5 days

moderate-altitude 2000-3000m
-1-2 weeks

high altitude 3000m+
-2+ weeks

extreme altitude 5000-5500m
-4+ weeks

Question 20

why different time for different altitudes?

Answer 20

to acclimatise to different po2 and give body enough time

Question 21

benefits of acclimatisation for cv and r system

Answer 21

-release epo inc after 3 hours altitude - peak 24-48 hours
-within 6 weeks, exposure to 4540 altitude red blood cell conc inc by 14%

-br and ventilation stabilise but remain elevated

-sv and q reduce as use of oxygen is efficient.
-10 days, q is lower at sub max than sea level
-hr is still elevated

-reduced altitude sickness, headaches, breathlessness

Question 22

what is thermoregulation

Answer 22

the process of maintaining internal core temperature

Question 23

what is normal human body temp

Answer 23

37 degrees

Question 24

what happens if core body temp rises

Answer 24

metabolic heat is transported to the circulating blood on the surface of the body/skin

releases by convection and evaporation of sweat

Question 25

what does excess sweating lead to

Answer 25

dehydration

decreased blood volume

Question 26

what happens if there is high humidity

Answer 26

high conc of h2o in air prevents sweating and leads to increased body temp

Question 27

what happens if body temp raises too much

Answer 27

hyperthermia

Question 28

when does body temp increase from exercising

Answer 28

high and prolonged exercise intensity

high air temp

high relative humidity

Question 29

what does the body do that produces metabolic heat

Answer 29

inc musc contraction

inc chemical reactions

Question 30

what is cardiovascular drift

Answer 30

upward drift in heart rate associated with a rise in body temp

Question 31

effect of temp inc on hr

Answer 31

10bpm hr inc with 1 degree body temp inc

Question 32

what happens when blood flow if directed to the skin

Answer 32

limits blood available for the working muscles and venous return

rise in temp alters function of enzymes and receptors
-effects chemical reactions

Question 33

body’s thermoregulatory response to heat and humidity on cv system

Answer 33

dilatiion of arterioles and capillaries to skin
-blood pooling in limbs
-inc blood flow

decreased blood volume, venous return, SV, Q and blood pressure
-increased hr to compensate
-inc strain on cv system
-reduced o2 transport to muscles

Question 34

body’s thermoregulatory response to heat and humidity on respiratory system

Answer 34

dehydration and drying of airways makes breathing difficult
-constriction of airways
-dec vol of air for gaseous exchange

inc bf to maintain o2 consumption
-inc oxygen ‘cost’ of exercise

high levels of sunlight inc effects of pollutants in air
-inc irritation of airways

Question 35

effect of heat on performance

Answer 35

exercise duration decreases
-build up on la in muscles

less oxygenated blood to working muscles has huge effects