Esercise

[dadddarrell2]

QUESTION 1

WHY IS IT BETTER TO EXERCISE WHEN THE RELATIVE HUMIDITY IS LOW?

multible choice answer

a - when relative humidity is high, the high level of water vapor in the air cause your sweat to evaporate at a slow rate.

b - when relative humidity is high, the high level of water vapor in the air lowers the amount of oxygen in the air

c - lower humidity levels faster fat metabolism

d - lower humidity levels decrease respiratory problems

[brachiopod]

When a liquid evaporates, it needs energy (heat) to do so. (Called the latent heat of evaporation)

Thus when sweat evaporates, it takes the energy required from your body which has a cooling effect on your body.

When humidity is low, sweat will evaporate easily, cooling your body quickly.

When humidity is high, there is a lot of water vapour in the air already, so your sweat will find it more difficult to evaporate and thus, the cooling of your body will be less effective.

So, now you should be able to work out the answer.

[Jackson74]

A is correct I think. All I remember is that sweat needs to evaporate to cool the body down. I did this in an experiment in my Sports Science degree, and remember losing a stone in water whilst exercising for an hour in a room with 10heaters on full blast.