Babies clenching their fists while swimming may be a normal physiological phenomenon, younger babies due to the grip reflex and normal hand function bit etc.. Babies make a fist when swimming is a normal physiological phenomenon: some babies, due to relatively small, the body is not yet fully developed, still have the grip reflex, can appear to make a fist with both hands. In addition, the normal human hand in completely relaxed, also presents a half fist situation, this is due to the existence of the human hand functional position of the factors. It is a normal situation. Babies need to always pay attention to the safety of babies when swimming, and infants need to pay attention all the time to avoid the occurrence of drowning due to their young age.