For someone managing type 1 diabetes, understanding their body's glucose response to physical activity could aid in effectively addressing nocturnal hypoglycemia. The purpose of this investigation was to examine the acute temporal associations between blood glucose and measures of moderate-vigorous physical activity (MVPA) through an accelerometer. Ten adolescent athletes with type 1 diabetes wore an accelerometer and continuous glucose monitor (CGM) consecutively for a minimum of 2 weeks. Physical activity was analyzed according to intensity indicating time spent in light, moderate, and vigorous intensities. Hypoglycemic episodes were defined as two successive CGM readings <70 mg/dL, at 5-min intervals, with an episode ending with at least two CGM readings >70 mg/dL. Incidence of nocturnal hypoglycemia occurred during 29% of the nights measured with an average duration of 52.33 ± 41.04 min. When combining total minutes of moderate and vigorous intensities a significant difference was observed between combined MVPA and number of nocturnal hypoglycemic episodes (62.92 min vs. 49 episodes, P = 0.02). Moderate intensity activity alone was not significant in predicting hypoglycemic events or duration. Vigorous intensity physical activity was a significant predictor of nocturnal hypoglycemia after controlling for sedentary and light intensity minutes, age, and gender (β = 0.21, P = 0.01) with an average time of 26 min of vigorous intensity. Engaging in vigorous intensity physical activity increased the risk of prolonged nocturnal hypoglycemia in adolescent athletes with type 1 diabetes. Incorporating accelerometers into patient care could prove beneficial when making further recommendations for athletes.
Keywords: Accelerometer; Clinical exercise; Glycemia; Sports medicine.