Thermoregulation and Thermal Stress W8

Question 1

What is the average resting body core temperature?

Answer 1

36.5-37.5 degrees

Question 2

What is the core temperature the body can safely up during heat?

Answer 2

40 degrees

Question 3

What is the core temperature safely drop to in the cold?

Answer 3

35 degrees

Question 4

How is core temperature assessed?

Answer 4

Oesophageal temperature
Rectal temperature
Stomach temperature
Oral Temperature
Tympanic Temperature

Question 4

What is core temperature?

Answer 4

Temperature of the hypothalamus

Question 5

How is heat loss?

Answer 5

Blood reaching the skin
Sweating

Question 5

How is heat heat conservation/production?

Answer 5

Shivering thermogenesis
Voluntary muscular activity
Non-shivering thermogenesis

Question 6

What is dehydration?

Answer 6

Loss of fluids from the body

Question 7

Why does core temperature increase during exercise in heat?

Answer 7

Reduced gradient between core and skin

Question 8

How does dehydration exacerbate heat stress impacts?

Answer 8

• Decreases sweat rate and plasma volume
• Further decrease cardiac output, maximal oxygen uptake, muscle strength and work capacity

Question 9

Why is high intensity exercise markedly impaired by a hot environment?

Answer 9

Due to competing regulatory demands for blood flow between thermoregulation, working muscle and CNS

Heat-related changes in skeletal muscle function and metabolism

Question 10

What are heat acclimatisation responses? (name at leas 4/8)

Answer 10

Improved cutaneous blood flow

Effective distribution of cardiac output

Lowered threshold for start of sweating

More effective distribution of sweat over skin surface

Increased sweat output

Lowered salt concentration of sweat

Lower skin and core temperatures and heart rate for standard exercise

Less reliance on carbohydrate catabolism during exercise

Question 11

What is hypothermia?

Answer 11

Core temperature below 35 degrees

Question 12

What are the physiological responses to exercise in the cold? (name at least 5/9)

Answer 12

Increased submaximal VO2

Decreased exercise capacity in water

Increased ventilation during submaximal exercise

Reduced skin blood flow

Lower lipid mobilisation

Increase lactate concentration

Increased central blood volume

Decreased heart rate during submaximal exercise

Release of leptin from adipose tissue

Question 13

When do cold environment adaptations begin?

Answer 13

After 1 weel