2.5.1. Flash Glucose Monitor
GESTATIONAL DIABETES
The participants were provided with a Flash Glucose Monitoring System (Abbott, Chicago, IL, USA) to wear for the entirety of the study period—a device that has previously been evaluated in pregnant women with type 1, type 2, and gestational diabetes. [Data from the CGM devices were downloaded to Microsoft Excel files using the FreeStyle Libre Software Version 1.0 software (Abbott, Chicago, IL, USA) and analyzed offline. Interstitial fluid glucose was measured and used as a proxy for blood glucose levels. The primary outcomes were 1 and 2 h postprandial glucose values after the start of each meal (breakfast, lunch, dinner). Secondary outcomes included fasting (value upon awakening), mean 24 h (midnight to midnight), peak and nadir glucose, time in target (3.3–7.8 mmol/L), time spent < 3.3 mmol/L, and time spent > 7.8 mmol/L. Daily mean 1 and 2 h postprandial outcomes were calculated using days 2 to 5 of the SHORT condition and days 2 to 5 of the LONG condition. Daily mean 24 h, peak and nadir glucose, time in target, time < 3.3 mmol/L, and >7.8 mmol/L were calculated using days 2 to 5 of the first condition completed and days 2 to 4 of the second condition completed, as the glucose monitor stopped recording partway through the 14th day of the study period. The first day of each condition was excluded in order to not use data collected prior to the exercise stimulus. While the CGM records interstitial fluid glucose values in five-minute intervals, only 15 min average blocks are able to be exported. The area under the curve was also calculated within 1 and 2 h of each meal to account for glucose control. The participants’ values for each outcome within each condition (NORMAL, SHORT, LONG) were averaged and contributed to the groups’ means.