Heat therapy can help you sleep. Also known as thermotherapy, heat therapy refers to applying heat to your body. "Heat healers" help your body's thermoregulation process. Performing this kind of therapy 90 minutes before bed allows your core body temperature to rise temporarily followed by a fast decline back to the normal range. This helps kickstart your internal clock into gear. In response to the cooldown, your brain will begin producing melatonin—otherwise known as the "sleep hormone."