W6 - Exercise in the Cold Flashcards
1
Q
What are the 2 types of cold environments?
A
- Cold by altitude
- Cold water immersion
2
Q
How does heat loss differ in cold water?
A
- Water thermal conductivity 26x greater than air - at a low water temperature a person can get hypothermia, heat loss is a lot more rapid
- C + K + R + E heat loss is 4 times greater
- Heat loss increases in moving water - temperature gradient increases as cold water moves towards you as warmer water moves away
- Hypothermia occurs in water well over 0°C
3
Q
How does the body respond to cold water immersion?
A
- Cold shock response
– Gasp
– Hyperventilation
– Vasoconstriction- Cold incapacitation
- Blood flow to periphery reduced
– Arms and legs reduce ability to keep afloat - Less effective at swimming
4
Q
What are the 3 methods of thermoregulatory control in the cold?
A
- Vasoconstriction - prevents blood flow to extremities
- Non-shivering thermogenesis Brown adipose tissue
– chemical heat production (performs a reaction to generate heat) - Shivering ~4-5x increase in heat production
+ Behavioural responses(make hot drink, add clothing)
5
Q
How do we habituate to the cold?
A
- repeated cold exposure without heat loss
- Skin vasoconstriction and shivering responses blunted
- core temp drops further
6
Q
Describe how we acclimate metabolically to the cold
A
- Repeated cold exposures with heat loss
- Increased metabolic and shivering heat production
7
Q
Describe how we acclimatise insulation
A
- when metabolic cant stop heat loss
- increased vasoconstriction
8
Q
How does our body maintain the fluid balance in the cold?
A
- Water losses in the cold
- Blunted thirst - do not ingest as much
- ↑ respiratory
- Cold-induced diuresis (more urination)
- May not be sweating but need to replace water loss
9
Q
Does cryotherapy and cold water immersion increase recovery?
A
- Speeds up recovery
- But unsure if it blunts adaptations in the muscle
- Ice blunts muscle adaptations
- Ice decreases muscle soreness
