Effect of antecedent exercise on the glycaemia-increasing response of a short sprint: implications for blood glucose management for individuals with type 1 diabetes mellitus

[Truncated abstract] Individuals with type 1 diabetes mellitus (T1DM) manage their blood glucose levels by maintaining a careful balance between carbohydrate intake and exogenous insulin administration. Although regular exercise affords numerous benefits to individuals with T1DM, it can further complicate this balance, making management of blood glucose levels more difficult. For example, moderate-intensity activity causes a rapid decline in blood glucose levels both during exercise and early recovery, discouraging many individuals with T1DM from participating in exercise due to the increased risk of hypoglycaemia, a potentially life threatening condition. However, it is important to note that not all types of exercise cause a decline in blood glucose levels. For instance, it has recently been found that performance of short maximal sprints can attenuate the fall in blood glucose levels both during (Guelfi et al., 2005) and after moderate-intensity exercise (Bussau et al., 2006; Bussau et al., 2007; Guelfi et al., 2005) in individuals with T1DM. However, before short maximal sprints can be safely added to exercise guidelines for individuals with T1DM, factors that may reduce the glycaemia-increasing benefit of a sprint need to be considered. In particular, the effect of an antecedent bout of moderate-intensity exercise on the glycaemia-increasing response to a 30-second maximal sprint performed several hours later needs to be investigated given that previous research has shown a blunted counterregulatory hormone response to a second bout of moderate-intensity exercise after an identical bout of exercise performed several hours prior (Galassetti et al., 2001b).