Why is building up to full uniform/padding a good idea in preventing heat illness during practices?

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Why is building up to full uniform/padding a good idea in preventing heat illness during practices?

students can run faster when not weighed down by gear.

students need to get acclimatized to heat and exercise intensity before wearing heavy gear.

students need to build up their muscles before wearing full gear.

students need to get acclimatized to heat and exercise intensity before wearing heavy gear.

Explanation:

Using tight and heavy gear such as sports uniforms, padding, and helmets, can raise the possibility of developing a heat illness. This issue is important because external heat stroke is currently the leading cause of preventable death in high school athletes. Therefore, building up to the full uniform helps students to get acclimatized to exercising despite the heat.