The endocrine system pervades all of sports, just as it pervades all of biology and medicine. The importance of endocrine glands and their hormonal products and effects in sports is axiomatic to the endocrinologist, and the actions in athletic activity of key hormones such as adrenaline are even known to much of the lay public. The other chapters in this textbook provided a systematic review of the effects of these hormones on organ systems, including those involved in sports as well as in health and disease. This chapter will only provide brief review of endocrine physiology that is relevant to sports. Such reviews can be readily found in other publications (1) as well as in the other chapters of this book. This chapter will instead focus on the role of hormones in the international sports arena, an arena that is populated by professional athletes, aspiring athletes, and the weekend warrior public of essentially all countries.
Unlike classic endocrinology, where primarily endogenous hormones play a role in both health and disease, exogenous hormones taken supraphysiologically as well as physiologically have a major role in contemporary sports endocrinology (2). Consequently, sports endocrinology often collides with the administrative, regulatory, and legal bodies that reside at its intersection with sports events (2, 3). While systematic research will inform the basis of much of this chapter, anecdotes taken from sport can also be provocative if not informative (3). For example, consider the role of thyroid hormone replacement in the athlete who has hypothyroidism, a situation recently manifest by a pitcher in major league baseball who had surgery for thyroid cancer. Without much research support, the temptation exists to try to enhance this athlete’s performance by increasing his thyroid hormone dose before he is scheduled to pitch. At the other end of this particular spectrum is the athlete who chronically abuses androgens. Cases that also challenge the endocrinologist can fall in between these two extremes, such as glucose regulation for a diabetic footballer between games and during games and the cricketer who uses amphetamines intermittently.
While the use of hormones is at the centre of classic endocrinology, the medical periphery that is the ambit of some of sports endocrinology lurches beyond, into exercise pills and gene doping (1–4). It will become apparent that there is a paucity of controlled studies that demonstrate performance-enhancing effects of most of the agents abused by athletes (5). However, when all of the evidence is examined, exogenous androgens and perhaps growth hormone do seem to enhance athletic performance.
Role of the endocrine system in maintaining glucose homeostasis in health and disease
