W10R - Human Thermoregulatory Adaption in Hot Environments

Question 1

What experimental routine was used to check responses to hot environment in different populations?

Answer 1

Subjects step up and down on bench with height adjusted to give workload of 216 kg M/min at rate of 12 steps/min

Oxygen consumption required = 1 LPM

4 hours at 33.9 deg C dry bulb (32.2 deg C wet bulb)

Air flow: 24 m/min

Question 2

What acclimatisation procedure was used for Bantus + white medical students?

Answer 2

12 days of work, 4 h/day, air temperature of 36 deg C dry bulb (33.8 deg C wet bulb)

Air flow of 24m/min

Question 3

What is the predominant staple of Bushmen?

Answer 3

Mongongo nut

600 cal/100g

Question 4

What are the major constituents of desert Bushmen diet?

Answer 4

33% mongongo nuts, 37% meat, 30% vegetables

Question 5

Describe Bushmen acclimatisation to work in heat stress

Answer 5

Partially acclimatised based on rectal temp and HR being intermediate between non-acclimated and acclimated whites but with lower sweat rates than acclimated whites

Question 6

Why do Arabs perform poorly in heat experiment?

Answer 6

Incr HR indicates poor physical conditioning

Arabs wear clothing that in hot, dry environment minimises conductive, radiant energy gains. Reduces heat stress by trapping boundary of stale air between skin and cloth insulating it.

Heat stress adaptation is cultural more than physiological