Final answer:
Endorphins are chemicals released in the body during exercise that can boost mood and metabolism.
Step-by-step explanation:
When Melissa exercises, her mood and metabolism receive a boost thanks to certain chemicals being released in her body. These chemicals, known as endorphins, are neurotransmitters that help reduce pain and increase feelings of pleasure or euphoria. They are produced by the central nervous system and released by the pituitary gland.
Learn more about Endorphins and their role in boosting mood and metabolism during exercise