The endocrine system is made up of glands that produce and secrete hormones throughout the body. These hormones regulate physiological processes and help maintain homeostasis. The endocrine system functions to control mood, growth, development, organ function, metabolism, and reproduction by regulating hormone release. The endocrine system also plays an important role in exercise and fitness by influencing hormone regulation, energy metabolism, adrenaline release, cortisol response, growth hormone production, thyroid function, endorphin release, and hormonal adaptations to exercise.