The 10-s maximal sprint: a novel approach to counter an exercise-mediated fall in glycemia in individuals with type 1 diabetes.
OBJECTIVE
To investigate whether a short maximal sprint can provide another means to counter the rapid fall in glycemia associated with moderate-intensity exercise in individuals with type 1 diabetes and therefore decrease the risk of early postexercise hypoglycemia.


METHODS
In the study, seven male subjects with type 1 diabetes injected their normal insulin dose and ate their usual breakfast. When their postprandial glycemia fell to approximately 11 mmol/l, they pedaled at 40% Vo(2peak) for 20 min on a cycle ergometer then immediately engaged in a maximal 10-s cycling sprint (sprint trial) or rested (control trial); the sprint and rest trials were administered in a counterbalanced order.


RESULTS
Moderate-intensity exercise resulted in a significant fall (P < 0.05) in glycemia in both trials (means +/- SE: 3.6 +/- 0.5 vs. 3.1 +/- 0.5 mmol/l for sprint and control, respectively). The subsequent short cycling sprint opposed a further fall in glycemia for 120 min, whereas in the absence of a sprint, glycemia decreased further (3.6 +/- 1.22 mmol/l; P < 0.05) after exercise. The stabilization of glycemia in the sprint trial was associated with elevated levels of catecholamines, growth hormone, and cortisol. In contrast, these hormones remained at stable or near-stable levels in the control trial. Changes in insulin and free fatty acid levels were similar in the sprint and control trials.


CONCLUSIONS
These results suggest that after moderate-intensity exercise, it is preferable for young individuals with insulin-treated, complication-free type 1 diabetes to engage in a 10-s maximal sprint to acutely oppose a further fall in glycemia than to only rest. The addition of the sprint after moderate-intensity exercise provides another means to reduce the risk of hypoglycemia in active individuals with type 1 diabetes.
Bussau
Vanessa A
VA
School of Human MovementExercise Science, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia. vbussau@cyllene.uwa.edu.au
Ferreira
Luis D
LD
Jones
Timothy W
TW
Fournier
Paul A
PA
D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000503:physiopathology*; D004837:Epinephrine / Q000097:blood; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005934:Glucagon / Q000097:blood; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007003:Hypoglycemia / Q000517:prevention & control; D007328:Insulin / Q000097:blood; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009638:Norepinephrine / Q000097:blood; D012420:Running / Q000502:physiology*
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D019382:Human Growth Hormone; D019344:Lactic Acid; D005934:Glucagon; D006854:Hydrocortisone; D009638:Norepinephrine; D004837:Epinephrine