Year
2023
Degree Name
Doctor of Philosophy
Department
School of Medical, Indigenous and Health Sciences
Abstract
This thesis investigates the short- and longer-term feasibility and effectiveness of prescribing an individualised time to exercise, based on continuous glucose monitoring (CGM) derived time of peak hyperglycaemia, in individuals with type 2 diabetes (T2D). The Timing Exercise Prescription (TEP) study was designed to examine the impact of personalising the current aerobic physical activity guidelines (i.e., ≥150 min/week moderate-intensity aerobic activity) by prescribing a time to exercise on cardiometabolic health, adherence, and quality of life. Chapter 2 details the TEP Study design and protocol. The overarching aim was to compare the effects of prescribing exercise at the time-of-day when peak hyperglycaemia occurs (ExPeak) to exercise not at time of peak hyperglycaemia (NonPeak) and standard-care control (CTL) in individuals with T2D. Participants in ExPeak and NonPeak were prescribed 22 min/day of moderate-intensity aerobic exercise. ExPeak began daily exercise sessions 30 min before time of peak hyperglycaemia and NonPeak began 90 min after time of peak hyperglycaemia. Time of peak hyperglycaemia was determined from a two-week baseline CGM period. All exercise sessions were home-based (free-living), and participants maintained normal diet and medication throughout the trial. Changes in glycaemic and metabolic control, vascular function, body composition, quality of life and physical activity were examined.
Chapter 3 examined the feasibility of using CGM to prescribe an individualised time to exercise. The primary outcome was adherence to two weeks of ExPeak or NonPeak between groups and compared to habitual activity (i.e., baseline). Adherence was determined by the amount of total moderate to vigorous intensity activity (MVPA) participants accumulated per week, measured via accelerometry. Secondary outcomes examined changes in glycaemic control from CGM. Participants wore CGMs and accelerometers for two weeks before and during the intervention. Compared to habitual activity, participation in MVPA increased by 26% when an exercise time was prescribed (p<0.01), with no differences observed between intervention groups (p>0.26). Change in peak blood glucose was similar between groups, and not significantly lower compared to baseline (ExPeak by -0.44 ± 1.6 mmol/L and NonPeak by -0.39 ± 1.5 mmol/L, p=0.92).
Recommended Citation
Chang, Courtney Rochelle, Using Continuous Glucose Monitoring to Prescribe a Time to Exercise for Individuals with Type 2 Diabetes, Doctor of Philosophy thesis, School of Medical, Indigenous and Health Sciences, University of Wollongong, 2023. https://ro.uow.edu.au/theses1/1821
FoR codes (2008)
1106 HUMAN MOVEMENT AND SPORTS SCIENCE
Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.