No Cover Image

Journal article 553 views 134 downloads

Metabolic and physiological responses to graded exercise testing in individuals with type 1 diabetes using insulin pump therapy

Olivia McCarthy, Kasper Birch Kristensen, Merete Bechmann Christensen, Signe Schmidt Orcid Logo, Ajenthen G. Ranjan Orcid Logo, Chloe Nicholas, Steve Bain Orcid Logo, Kirsten Nørgaard, Richard Bracken Orcid Logo

Diabetes, Obesity and Metabolism, Volume: 25, Issue: 3

Swansea University Authors: Olivia McCarthy, Steve Bain Orcid Logo, Richard Bracken Orcid Logo

  • 62161.pdf

    PDF | Version of Record

    This is an open access article under the terms of the Creative Commons Attribution NonCommercial-NoDerivs License

    Download (1.07MB)

Check full text

DOI (Published version): 10.1111/dom.14938

Abstract

Aims1) To profile acute glycaemic dynamics during graded exercise testing (GXT) and 2) explore the influence of glycaemic indicators on the physiological responses to GXT in adults with T1D using insulin pump therapy.MethodsThis was a retrospective analysis of pooled data from four clinical trials w...

Full description

Published in: Diabetes, Obesity and Metabolism
ISSN: 1462-8902 1463-1326
Published: Wiley 2023
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa62161
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: Aims1) To profile acute glycaemic dynamics during graded exercise testing (GXT) and 2) explore the influence of glycaemic indicators on the physiological responses to GXT in adults with T1D using insulin pump therapy.MethodsThis was a retrospective analysis of pooled data from four clinical trials with identical GXT protocols. Data was obtained from 45 adults with type 1 diabetes using insulin pumps ([30 females], HbA1c: 59.5±0.5 mmol.mol-1 [7.6±1.0 %], age: 49.7±13.0 years, diabetes duration: 31.2±13.5 years, V̇O2peak: 29.5±8.0 mL.min-1.kg-1). Integrated cardiopulmonary variables were collected continuously via spiroergometry. Plasma glucose (PG) was obtained every three minutes during GXT as well as the point of volitional exhaustion. Data were assessed via general linear modelling techniques with age and gender adjustment. Significance was accepted at P ≤0.05.ResultsDespite increasing duration and intensity, PG concentrations remained similar to rest values (8.8±2.3 mmol.L-1) throughout exercise (p=0.419) with an overall change of +0.3±1.1 mmol.L-1. Starting glycaemia bore no influence on subsequent GXT responses. Per 1% increment in HbA1c there was an associated decrease in V̇O2peak of 3.8 mL.min-1.kg-1 (p<0.001) and powerpeak of 0.33 watts.kg-1 (p<0.001) concomitant with attenuations in indices of peripheral oxygen extraction ([O2 pulse] -1.2 mL.beat-1, p=0.023).ConclusionIn adults with long-standing type 1 diabetes using insulin pump therapy, circulating glucose remains stable during a graded incremental cycle test to volitional exhaustion. Glycaemic indicators are inversely associated with aerobic rate, oxygen economy and mechanical output across the exercise intensity spectrum. An appreciation of these nexuses may help guide appropriate decision making for optimal exercise management strategies.
Keywords: Type 1 diabetes, exercise, cardiopulmonary exercise testing, insulin pump therapy, graded exercise testing, plasma glucose
College: Faculty of Science and Engineering
Issue: 3