1. BND Sports Science Impact of cold climates on athletes

2. This lesson:

This lesson we will look at:

The effects a cold environment has on a performer.

Hypothermia and its consequences

The effects different types of clothing has on losing and gaining heat.

3. Exercise in cold climates

Exposing performers to cold produces psychological and physiological effects.

The severity of the cold and the sport/activity the performer is involved in determines the effect on performance.

4. Cold climates

A reasonably cold/cool environment can actually have a good affect on performance.

The CV system does not need to divert blood to lose heat, as well as supplying the working muscles.

This means the heart does not have to work as hard as in the heat.

5. Cold climates

It is in cool climates that record times are recorded .

If the temperature drops drastically (causing core body temperature to drop), then performanceisaffected.

Then the performers VO 2max will be reduced.

6. So how can an individual gain heat?

When the body is exposed to heat it uses mechanisms to try to lose this excess heat.

The body when cold, tries to gain or retain heat.

There are three ways it tries to do this:

Constrictionof blood vessels at skin surface.

Thermogensis(non-shivering)

Shivering

7. Gaining or retaining heat

The vasoconstriction of blood vessels tries to prevent heat being lost through the skin.

Blood is directed away from the skins surface to stop it being cooled by the cold environment.

If a person has more body fat it can also help by insulating the body.

8. Gaining or retaining heat

Non-shivering thermogensis an increase in a persons metabolic rate this generates body heat.

Shivering skeletal muscle contracts and relaxes, without the individuals conscious control. This can also increase metabolic rate.

9. What conditions/injuries could extremely cold conditions cause? 10. Cold climates

Cold climates can lead tofrostbiteorhypothermia .

Frostbite :

Frostbite usually affects the fingers and toes.When a part of a persons body becomes very cold, the blood supply to that part is greatly reduced. When this happens the body tissue is frozen.

11. Frostbite : 12. Cold climates

Ice crystals form inside and rupture. This results in the bodys cells being destroyed.

The area affected usually goes purple/red, blisters and fills with blood.

When this happens, the body part generally has to be amputated to stop the infection from spreading.

13. Cold climates

Hypothermia:When the core body temperature drops below 35 C or lower.

How bad an individuals condition is depends on how low the body temperature drops.

If it drops below 30C, both the cardiac and respiratory system can fail.

14. Hypothermia:

Mild 32.2 - 35C

Moderate 26.6 32.2C

Severe less than 26.6C

15. Effects of the cold on the CNS

Mild Agitation and shivering

Moderate Confused but able to speak; shivering stops.

Severe pupils now also dilated; then individual slips into a coma.