Effect of Exercise and Meals on Continuous Glucose Monitor Data in Healthy Individuals Without Diabetes

Objective: The aim of these analyses was to characterize the effect of exercise and meals on glucose concentrations in healthy individuals without diabetes. Methods: Healthy individuals without diabetes (age ≥6 years) with nonobese body mass index were enrolled at 12 centers within the T1D Exchange Clinic Network. Participants wore a blinded Dexcom G6 for up to ten days. Throughout this sensor wear, participants completed a daily log indicating times and type of any exercise and start times of meals and snacks. Results: A total of 153 participants (age 7-80 years) were included in the analyses. Exercise induced a mean change of −15 ± 18 mg/dL from baseline to nadir sensor glucose level. Mean nadir glucose concentration during nights following exercise days was 82 ± 11 mg/dL compared with 85 ± 11 mg/dL during nights following nonexercise days ( P = .05). Mean change from baseline to nadir sensor glucose level during aerobic exercise was −15 ± 18 and −9 ± 12 mg/dL for resistance exercise ( P = .25). Overnight nadir glucose during nights following aerobic and resistance exercise was 83 ± 12 and 76 ± 14 mg/dL, respectively ( P = .25). Overall mean peak postprandial glucose per participant increased from 93 ± 10 mg/dL premeal to 130 ± 13 mg/dL with an average time to peak glucose per participant of 97 ± 31 minutes. Consumption of alcohol on the day prior did not impact overnight mean or nadir glucose. Conclusion: The present analysis provides important data characterizing the effect of exercise and meals on glucose in healthy individuals without diabetes. These data provide a repository to which future therapies, whether pharmacologic or technologic, can be compared.