Exercise in Heat
Cards (12)
- Thermoregulationthe process that allows the body to maintain its core internal temperature
- Thermoreceptorsdetect change in temperature
- What Happens When Temperature Goes Up
- sweating cools the body down by vasodilating arterioles to skin
- can lose 2-3l per hour
- dehydration occurs which impairs the bodys thermoregulation
- core temperature will rise
- Hyperthermia
- significantly raised core body temperature
- caused by high intensity & prolonged activity, high air temp, & high humidity
- Cardiovascular Driftan upwards drift on HR associated with a risk in body temperature1 degree increases HR by 10bpmlimits blood flow to muscles & alters chemical reactions
- Cardiovascular Effects
- dilation of arterioles & capillaries going to skin, increases blood flow & pooling to limbs
- decreased blood volume, venous return, SV, Q, & blood pressure
- increase HR & strain on overall cardiovascular system
- reduced oxygen transport to working muscles
- Thermoregulatory & Respiratory Effects
- dehydration & drying of airways
- increased mucus production
- constriction of airways
- coughing & wheezing
- decreased volume of air for gaseous exchange
- Overall Effects
- increased cost of oxygen
- decreased aerobic energy production
- increased anaerobic energy production
- carb stores used more quickly
- lactic acid accumulates quicker causing earlier fatigue
- Pre-Competition
- increases onset of sweating
- decrease in electrolyte loss limits fatigue & cramping
- cardiac distribution more efficient
- cooling aids reduce core temp
- During Competition
- pacing adapted
- wear appropriate clothing, light compression wear
- rehydrate with hypertonic
- Post Competition
- return core body temp, cold towels
- rehydrate using isotonic to replace fluid glucose & electrolytes
- Effect On Endurance Performers
- higher temp = decreased performance
- events are affected differently depending on intensity of activity
- higher rate of perceived exertion