5 Acclimatisation and habituation to cold

Question 1

Hypothermic adaptation

Answer 1

-Repeated immersions in cold water (e.g. 10 x 45 min in 15°C) lowers the threshold for the onset of shivering
-The sensitivity of the response is unchanged
-Is the adaptation specific to the deep body temperatures
experienced during acclimation?

Question 2

Cold-induced vasodilatation (CIVD) 2

Answer 2

– May protect cold indigenous populations against cold injuries and improve manual dexterity & tactile sensitivity
- May be a thermoregulatory response to increase heat loss in response to increased in Tcore

Question 3

Cold-induced vasodilatation (CIVD) 1

Answer 3

Decreased transmitter release from adrenergic nerve endings in AVAs causes a reduction in vasoconstriction
• Increased release of vasodilator substance
• Temperature-dependant blockade of the neuromuscular junction at the AVA