The Endocrine System: Metabolic Effects of the Pancreatic, Adrenal, Thyroidal, and Growth Hormones

Abstract

The purpose of this chapter is to review, from a historical perspective, the role of the key endocrine glands in modulating the metabolic responses to acute and chronic exercise. Its scope is limited to the metabolic effects of hormones released by the pancreas (insulin and glucagon), adrenal glands (catecholamines and glucocorticoids), anterior pituitary (growth hormone), and thyroid (thyroxine and triiodothyronine) that play a critical role in regulating substrate mobilization and utilization during muscular work. Although other hormones participate in the physiological response to exercise, their role is beyond the scope of this chapter. Although the study of endocrine diseases has enhanced our knowledge of hormonal actions, the chapter’s coverage is restricted to physiological responses in healthy individuals. We also provide a brief history of some of the important studies conducted on exercise and diabetes, as they have expanded our knowledge of the influence of the pancreatic hormones on metabolism. Information on the historical developments of the study of the endocrine system is also found in Chapters 6 and 8. Together, these three chapters cover a considerable portion of the broad field of endocrinology and metabolism in exercise physiology.