When I was first diagnosed my biggest worry was that I may not be able to play football again. Injecting myself every day was demoralising. Fortunately, I can feel the support around me—not just from my team-mates and the fans, but also the coaches, physios and nutritionists who all help me bring my A-game.
Ben Coker, English professional soccer player
Many athletes have treated their type 1 or type 2 diabetes while having successful careers. British rower Sir Steven Redgrave provides just one remarkable story of sporting success while managing diabetes mellitus. Other athletes include Jay Cutler (NFL), Gary Hall (swimmer), Wasim Akram (cricket), Henry Slade (rugby union) and the all-diabetic men’s professional cycling team Novo Nordisk, who compete with fully rostered type 1 and type 2 diabetic teams.
In this chapter we briefly review key clinically relevant pathophysiology of each type of diabetes. We then outline:
how diabetes can be managed effectively during physical activity
how physical activity can help patients control or reverse diabetic symptomology
medical considerations for clinicians to consider when managing the diabetic athlete.
Most persons with diabetes fall into two broad categories: type 1 and type 2. There are other types of diabetes, but they are rare and will not be discussed in this chapter.
Type 1 diabetes, which was previously known as ‘juvenile-onset’ diabetes, is thought to be an inherited autoimmune disease, in which antibodies are produced against the beta cells of the pancreas, ultimately resulting in the absence of endogenous insulin production. The incidence of type 1 diabetes varies throughout the world but represents approximately 10–15% of diabetic cases in the Western world.
The onset commonly occurs in childhood and adolescence but can become symptomatic at any age and is manifested by low or undetectable levels of plasma C-peptide. Insulin administration is essential to prevent ketosis, coma and death. The aims of treatment are tight control of blood glucose levels and prevention of microvascular and macrovascular complications.
Type 2 diabetes, previously known as ‘maturity-onset’ or ‘adult-onset’ diabetes, is typically a disease of later onset, although in developed countries it is increasingly seen in adolescents. It is linked to both genetic, environmental and lifestyle factors. It is characterised by diminished insulin secretion relative to serum glucose levels, in conjunction with peripheral insulin resistance, both of which result in chronic hyperglycaemia.
Approximately 90% of individuals with diabetes have type 2, and it is thought to affect 3–7% of people in Western countries. Some of the most recent World Health Organization (WHO) data for Europe suggests diabetes affects 10% of the European population of both ...