Sweat glands are coiled tubular structures that regulate the temperature of the human body. Human sweat glands are classified into three types: eccrine, apocrine, and apoeccrine. Eccrine glands are present all over the body and are responsible for water and salt loss through vaporization and perspiration, respectively. Apocrine glands are found mainly in the skin's dermis layer and secrete an oily substance that helps prevent bacteria and viruses from attaching themselves to the skin. These glands are thought to play a role in body odor because they produce enzymes that break down fatty acids into chemicals that cause malodor. Apoeccrine glands are located under the skin's surface and contain sebaceous material that is released when you exercise or become excited like people do when giving a speech or singing. This material is responsible for causing your skin to smell after it has been washed. Unlike other glands, apoeccrine glands cannot be felt under the skin. When you feel anxious or afraid, your heart rate increases, blood flows to the muscles, and perspiration also increases. This is because you need more energy to deal with these emotions. You can learn to control your sweating by focusing on your breathing.