Salty water, sand, concrete, rocks, and the sun must all be avoided by lifeguards. During the day, the sand and concrete may heat up, creating blisters and making it difficult for lifeguards to go barefoot. According to doctors, walking barefoot on concrete may induce joint and back discomfort. That is why lifeguards must wear special footwear. You may have seen lifeguards wearing flip-flops. Flip flops may not be suitable for this occupation due to their lack of support.