exercise physiology - pe

ambient temperature

the temperature of the environment the athlete is performing in

core temperature

temp in athletes body

heat loss from the body occurs is 4 different ways

• conduction 

• convection

• radiation

• evaporation

conduction

heat exchanged by 2 objects in contact

factors that determine rate

• dif in temp btn surfaces

• SA

convection

heat exchange by contact with fluid that is flowing

• when heat is carried away from body by air or water currents

radiation

occurs when the heat is transferred from a warmer body to the cooler surroundings without physical contact

evaporation

the cooling of the body as a result of the vaporisation of sweat

dehydration

occurs when the amount of water leaving the body is greater than the amount being taken in

body loses water by:

• breathing

• sweating

• urination and bowel movements

double heat load

a situation where the body is forced to deal with 2 forms of heat

cardiovascular drift

when the heart rate increase to maintain cardiac output caused by a decrease in stroke volume

hyperthermia

• if the body becomes too hot

• directs blood flow to skin, blood vessel vasodilate 

• heat lost through sweat

• body loses too much fluid, increase in core temp

fluid replacement - pre exercise

• 600ml 3-4hrs before game

• 400ml just before

• avoid caffeine causes increased fluid loss

fluid replacement - during and post exercise

• during: 200ml of water ever 15min

• post: for every 1L of sweat loss, consume 1.5L

heat acclimisation

when heat tolerance is improved by repeated exposure to hot environments

major adaptions to heat acclimatisation - sweating

• increased blood pladma vol - more fluid stored in blood, increase time before dehydration

• increased sweat rate - sweat glands increasing in size

• start sweating at a lower core temp

• sweat becomes more dilute and is distributed over the body for effectively, keeping salt in the body

major adaptions to heat acclimatisation - cardiovascular

• lower core and sin temp

• lower HR

• greater cardiac output

• increased blood vol

strategies to help with exercising in the heat

• hydration

• clothing

• pre-cool body

• acclimatise

• protection from the sun

humidity

amount of water vapor that exists in the air

higher humidity will:

• increase sweat rate

• increase loss of fluid

• decrease evaporation heat loss

• decrease performance

body physiological changes to cold weather

• peripheral vasoconstriction - blood flow away from skins surface

• shivering - involuntary muscular contractions

• piloerection - when the hairs on the body stand on end and trap a warm layer of air

strategies to help cope with exercising in the cold

• experiment with length of warm up

• layered clothing

• psychological acclimatisation

• adequate fluid replacement

high altitude compared to sea level

• the barometric pressure is lower and air is thinner

• fewer air molecules available

• less O2 entering lungs with each breath

• small pressure particle difference btn 02 in alveoli and venous blood in capillaries, makes diffusion more difficult

acute adaptations of altitude

• increased respiratory rate

• increased tidal vol

• increased nausea

• decrease plasma vol to increase concentration of hemoglobin

chronic adaptations of altitude

• increased hematocrit - % of RBC in the blood

• increased mitochondria

• increased anaerobic enzymes 

• increased capillaries

• increased myoglobin 

energy sources

• ATP/CP

• lactic acid/anaerobic

• aerobic 

fuel sources

• carbohydrates

• fats

• protein

• creatine phosphate

glycemic index

ranking carbohydrates based on their immediate effect on blood glucose levels

legal performance enhancers

• protein powders

• caffeine

• creatine

illegal performance enhancers

• anabolic steroids

• EPO

• blood doping

blood doping strategies

• blood transfusions

• EPO

• synthetic oxygen carriers

training programs 161