Fasted high-intensity interval and moderate-intensity exercise do not lead to detrimental 24-hour blood glucose profiles

Research output: Contribution to journalArticle

Authors

  • Sam N Scott
  • Matt Cocks
  • Rob C Andrews
  • Tejpal S Purewal
  • Daniel J Cuthbertson
  • Anton J M Wagenmakers
  • Sam O Shepherd

Colleges, School and Institutes

External organisations

  • Liverpool John Moores University
  • UNIVERSITY OF EXETER
  • The Royal Liverpool and Broadgreen University Hospital Trust, Liverpool L7 8XP, UK.
  • University of Liverpool

Abstract

Aims: To compare the effect of a bout of high-intensity interval training (HIT) with a bout of moderate-intensity continuous training (MICT) on glucose concentrations over the subsequent 24h period.

METHODS: Fourteen people with type 1 diabetes (duration of type 1 diabetes 8.2±1.4 years), all on basal-bolus regimen, completed a randomised, counterbalanced, crossover study. Continuous glucose monitoring was used to assess glycaemic control following a single bout of HIT (6 x 1min intervals) and 30 mins of moderate-intensity continuous training (MICT) on separate days, compared to a non-exercise control day (CON). Exercise was undertaken following an overnight fast with omission of short-acting insulin. Capillary blood glucose samples were recorded pre and post-exercise to assess the acute changes in glycaemia during HIT and MICT.

RESULTS: There was no difference in the incidence of or percentage time spent in hypoglycaemia, hyperglycaemia or target glucose range over the 24h and nocturnal period (24:00-06:00h) between CON, HIT and MICT (P>0.05). Blood glucose concentrations were not significantly (P=0.49) different from pre to post-exercise with HIT (+0.39±0.42 mmol/L) or MICT (-0.39±0.66 mmol/L), with no difference between exercise modes (P=1.00).

CONCLUSIONS: HIT or 30 mins of MICT can be carried out after an overnight fast with no increased risk of hypoglycaemia or hyperglycaemia, and provided the pre-exercise glucose concentration is 7-14 mmol/L, no additional carbohydrate ingestion is necessary to undertake these exercises. As HIT is a time-efficient form of exercise, the efficacy and safety of long-term HIT should now be explored.

Details

Original languageEnglish
JournalThe Journal of clinical endocrinology and metabolism
Early online date24 Sep 2018
Publication statusE-pub ahead of print - 24 Sep 2018