A person wearing a life jacket cools how much faster while swimming compared to at rest?

• A. 15%
• B. 25%
• C. 35%
• D. 50%

Answer: (C)

When a person is swimming while wearing a life jacket, the body encounters additional movement and exposure to water that enhances heat loss through convection and evaporation processes. When at rest, the body loses heat primarily through conduction and radiation, with minimal movement of water around the body. However, when a person is actively swimming, the combination of moving through water and the cooling effect of the water on the skin results in a significantly higher rate of heat loss.

Research indicates that individuals in the water can experience a considerable increase in heat loss due to these mechanisms. Cooling while swimming can be up to 35% more effective compared to resting in still water. This percentage reflects the enhanced heat exchange dynamics experienced during physical activity in cold water, leading to a more rapid decrease in core body temperature.

Therefore, the understanding of this cooling dynamic is crucial for safety in aquatic environments, especially for those wearing flotation devices like life jackets while engaged in strenuous activities such as swimming.