👉 Underparts are the areas of a body that are covered by skin and are usually less than 1/3rd of the total area of the body. These areas include the head, neck, shoulders, arms, legs, back, and hands. Underparts can vary depending on the individual's body type, age, and lifestyle. Some people may have a more pronounced underpart compared to others due to genetics or hormonal changes. Underparts are often associated with certain physical traits such as a muscular