What is a significant factor in preventing heat loss?

Wearing multiple layers is essential in preventing heat loss, particularly in colder environments. The concept behind layering is that it creates air pockets between each layer of clothing. These air pockets serve as insulation, trapping warm air close to the body and thereby reducing the amount of heat that escapes. Each layer can trap heat efficiently, and this is especially beneficial when outdoors in varying temperatures.

Additionally, layers can be adjusted based on activity level or environmental conditions, providing versatile protection against heat loss. While being well-conditioned can contribute to overall body efficiency and thermal regulation, it does not directly impact heat retention in the same way that wearing multiple layers does.