The purpose of this study was to investigate the concurrent and lagged effects of daily exercise on daily blood glucose level and affect among persons with type 1 diabetes (T1D). 199 persons with T1D (Mage = 46.82) completed a 14-day diary in which they reported on their engagement in moderate to vigorous exercise for 30 min and positive and negative affect. Daily blood glucose (BG) was gathered through study-provided glucometers. Multilevel modeling examined the effects of daily variability in (within-person effects) and average levels of (between-person effects) daily exercise on BG and affect. On days when persons with T1D reported they exercised moderately to vigorously for 30 min, they had lower mean BG, higher risk for low BG, lower negative affect, and higher positive affect on the same day as well as lower mean BG on the following day. Engaging in daily exercise is important in managing daily blood glucose and affect among persons with T1D, but can be complicated by hypoglycemia.
