Vinutha Shetty, Paul Fournier, Tim Jones, Liz Davis
Study Staff: Nirubasini Paramalingam, Adam Retterath, Heather Roby; Ray Davey
Study summary: current recommendations for carbohydrate supplementation to prevent exercise-induced hypoglycaemia in individuals with type 1 diabetes (T1D) do not take into account blood glucose levels during exercise. Our objective was to investigate the effect of blood glucose levels on carbohydrate requirements to maintain stable glycaemia during exercise in individuals with T1D at basal insulin levels and to determine the underlying glucoregulatory mechanisms.
We subjected eight healthy individuals with T1D to a euglycaemic clamp, whereby euglycaemia was maintained by infusing insulin at basal rates with concomitant infusion of deuterated glucose for determining glucose kinetics. Participants were then randomized to undergo either euglycaemic or hyperglycaemic clamp, following which they performed 40 minutes of exercise at 50% VO2peak, on 2 separate days using a randomised counterbalanced study design. The glucose levels maintained during euglycaemic and hyperglycaemic clamp was 4.5-6.0 and 9.5-10.5mmol/L respectively. The glucose infusion rate (GIR), levels of glucoregulatory hormones and rates of glucose appearance (Ra) and disappearance (Rd) were compared between conditions.
Plain language summary: The common fear of exercise induced hypoglycaemia prevents individuals with T1DM from participating in sports and games. The goal of this study was to determine if hyperglycaemia prior to and during exercise, affects the amount of carbohydrate required to maintain stable glucose levels during and early after moderate intensity exercise under basal insulin conditions.
For this study we recruited young adults with T1DM, aged between 13 and 25 years old. Each participant performed an exercise on a stationary bike to determine their level of fitness. Subsequently, on 2 different days (with at least 1 week interval between study days), the participant exercised for short period of time while their blood glucose levels were maintained at two different levels during and after exercise. The amount of glucose that was required to maintain stable glucose levels were compared between the two trials.
Funder: Internal