Evidence of effort can be seen in the form of SWEAT. SWEAT is a natural bodily secretion that is produced when the body is under physical or mental stress. It is composed of water, salt, and other electrolytes, and is released through the pores of the skin. SWEAT is an important part of the body's cooling system, as it helps to regulate body temperature. It also serves as an indicator of how hard someone is working, as it is often visible on the skin after physical activity.