594-P: Exercise Timing Has Limited Effect on Glycemic Profile in a Cluster of Well-Controlled Youth with Type 1 Diabetes

Identifying the best exercise timing to mitigate hypoglycemia is critical for patients with type 1 diabetes (T1D). Despite the established health benefits, concerns persist regarding post-exercise glucose stabilization in this population. In a cross-sectional design of one hundred well-compensated individuals from Northwest Italy (55% female, 45% male; age: 16 ± 6 years; HbA_1c: 6.8 ± 1%), physical activity (PA), glycemic profiles, and psychometric traits were monitored. The timing, duration, intensity, and volume of PA were derived from a 7-day training log. Glycemic control was assessed through continuous glucose monitoring, including time in range (TIR; 70-180 mg/dL), time below range (TBR; <70 mg/dL), time below the extreme hypoglycemia range (TBER; <54 mg/dL), time above range (TAR; 180-250 mg/dL), time >250 mg/dL, mean glycemia (MGLU), and total daily insulin dose. Subjects were categorized based on the prevalent timing of exercise into three groups: morning (6am - 12pm), afternoon (12pm - 6pm), and night (6pm - 12 am). Non-exercising days (NO-activity) for each subject were also considered. The mixed model analysis for fixed effects revealed that TIR, TAR, TBER, and MGLU were significantly influenced by the timing of exercise. However, post-hoc analysis indicated that this difference was observed only when comparing NO-activity vs afternoon exercise. Pairwise comparisons showed no significant differences in TIR, TAR, TBER, and MGLU when comparing exercise timing (morning vs afternoon vs night). Additionally, active participants exhibited better quality of life, reduced fear of hypoglycemia, and improved diabetes management self-efficacy compared to their less active counterparts. The findings suggest that exercise timing may be secondary to the overarching goal of helping individuals with T1D develop a consistent and adherent exercise routine. This insight is valuable in guiding recommendations for managing glycemic control in T1D.