A 10-s sprint performed prior to moderate-intensity exercise prevents early post-exercise fall in glycaemia in individuals with type 1 diabetes.
OBJECTIVE
We investigated whether a 10-s maximal sprint effort performed immediately prior to moderate-intensity exercise provides another means to counter the rapid fall in glycaemia associated with moderate-intensity exercise in individuals with type 1 diabetes.


METHODS
Seven complication-free type 1 diabetic males (21.6 +/- 3.6 years; mean+/-SD) with HbA(1c) levels of 7.4 +/- 0.7% injected their normal morning insulin dose and ate their usual breakfast. When post-meal glycaemia fell to approximately 11 mmol/l, participants were asked to perform a 10-s all-out sprint (sprint trial) or to rest (control trial) immediately before cycling at 40% of peak rate of oxygen consumption for 20 min, with both trials conducted in a random counterbalanced order.


RESULTS
Sprinting did not affect the rapid fall in glycaemia during the subsequent bout of moderate-intensity exercise (2.9 +/- 0.4 mmol/l in 20 min; p = 0.00; mean+/-SE). However, during the following 45 min of recovery, glycaemia in the control trial decreased by 1.23 +/- 0.60 mmol/l (p = 0.04) while remaining stable in the sprint trial, subsequently decreasing in this latter trial at a rate similar to that in the control trial. The large increase in noradrenaline (norepinephrine) (p = 0.005) and lactate levels (p = 0.0005) may have contributed to the early post-exercise stabilisation of glycaemia in the sprint trial. During recovery, adrenaline (epinephrine) and NEFA levels increased marginally in the sprint trial, but other counter-regulatory hormones did not change significantly (p < 0.05).


CONCLUSIONS
A 10-s sprint performed immediately prior to moderate-intensity exercise prevents glycaemia from falling during early recovery from moderate-intensity exercise in individuals with type 1 diabetes.
Bussau
V A
VA
School of Human Movement and Exercise Science, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA, 6009, Australia.
Ferreira
L D
LD
School of Human Movement and Exercise Science, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA, 6009, Australia.
Jones
T W
TW
Department of Endocrinology and Diabetes, Princess Margaret Hospital, Subiaco, WA, Australia.|Centre for Child Health Research, Telethon Institute of Child Health Research, The University of Western Australia, Perth, WA, Australia.
Fournier
P A
PA
School of Human Movement and Exercise Science, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA, 6009, Australia. fournier@cyllene.uwa.edu.au.
D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000503:physiopathology*; D015444:Exercise / Q000502:physiology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D006728:Hormones / Q000097:blood; D006801:Humans; D007003:Hypoglycemia / Q000517:prevention & control*; D007328:Insulin / Q000627:therapeutic use; D007773:Lactates / Q000097:blood; D008297:Male; D012420:Running
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D006728:Hormones; D007328:Insulin; D007773:Lactates