Guest pro Emma Sproule teams up with young Tyrus and host Nykeem as they plunge into the science of swimming. Dr. Heather explains the three types of drag that push back against the thrust of the swimmer pushing through water: frictional drag, pressure drag, and wave drag. Emma aims for maximum thrust to counteract drag, and pro swimmers wear smooth caps and swim suits to minimize drag as well. Fun Fact: it is easier to hold your breath underwater because of the "mammalian diving reflex". There is evidence from rock paintings in Egypt that humans began to swim at least 10,000 years ago.