The purpose of sweat is to cool the body by sitting on the surface of the skin and allowing heat to escape from the body. Effective sweating is when someone is glistening as the moisture forms a cooling film over the skin. When sweat reaches the 'dripping' stage the body is struggling to effectively control the body temperature and will be less effective at cooling the body down. Whether someone glistens or drips, however, is not indicative of how hard they are working, it merely indicates how effectively they sweat. Factors such as the humidity and temperature of the environment you are working in and the clothing worn also have a significant effect on sweat production.