Week 8 - Thermoregulation and thermal stress Flashcards
What is our normal resting body core temperature?
36.5-37.5 degrees Celsius
- Fluctuation throughout the day
In the heat, core temperature can safely increase up to .. degrees Celsius?
40 degrees Celsius
In the cold, core temperature can safely drop to .. degrees Celsius?
35 degrees Celsius
Define core temperature.
defined as temperature of the hypothalamus, the thermoregulator centre of the body.
How can core temperature be assessed?
- Oesophageal temperature
- Rectal temperature
- Stomach temperature (swallowed telemetry pill)
- Oral temperature
- Tympanic temperature
a) Skin temperature
b) Cool mean skin temp
c) warm mean skin temp
d) hot mean skin temp
32-35 degrees Celsius
<30
30-34.9
>35
What does the homeostatic maintenance of body temperature require?
the operation of temperature sensors (peripheral and central thermoreceptors) and regulated effectors (adrenal medulla, sweat glands, skin arterioles, skeletal muscles).
Describe physiological control of thermoregulation when body temperature INCREASES.
Blood vessels dilates
Sweat glands secrete fluid
–> heat is loss
Describe physiological control of thermoregulation when body temperature DECREASES.
Blood vessels constrict
Sweat glands do not secrete fluid
—> Heat is conserved
Shivering generates heat
–> heat is generated
Physiological mechanisms of heat loss
Blood reaching the skin (vasodilation)
Sweating
Physiological mechanisms of heat conservation/production
Shivering thermogenesis
Voluntary muscular activity
Non-shivering thermogenesis
Heat exchange between the body and environment governed by biophysical properties. What are biophysical properties dictated by?
the surrounding temperature, humidity and air motion, sky and ground radiation + clothing
What is the most challenging environment for exercise? Why?
Hot and humid - we cannot evaporate sweat from our skin.
We gain/lose heat chiefly through our…
shell/skin
Is skin temperature regulated?
NO - unlike core temperature it’s not regulated and it varies across the body in response to thermal environment.