66-LB: Greater Time Spent in Hypoglycemia during Night Compared with Day during Intensified Training in Professional Cyclists with Type 1 Diabetes—A Prospective Observational Study
Authors: MOSER OTHMAR , ECKSTEIN MAX L. , MCCARTHY OLIVIA , RIDDELL MICHAEL , FONTANA FEDERICO Y. , SKROCE KRISTINA , FESTA LUCA , SOUTHERLAND PHIL , CHRISTIANSEN MARK P. , BODE BRUCE W. , STETTLER CHRISTOPH , SCOTT SAM N. , FISHER MILES , HAYES CHARLOTTE A. , BRACKEN RICHARD M. 
Published: June 2019

Aim: To compare time spent in pre-specified glycemic ranges in day and night-time during intensive training in professional cyclists with type 1 diabetes (T1D).
Methods: Fifteen male professional cyclists with T1D on multiple daily injections (age 27±4 years, duration T1D 11±5 years, BMI 21.6±1.5 kg·min-2, HbA1c 7.2±0.7%, O2max 73±4 ml·kg·min-1) performed road cycle sessions (50-90% of the anaerobic threshold, duration 1-6 hours) over 9 consecutive days. Time spent in pre-specified glycemic ranges was compared between day and night time using paired t-test and Wilcoxon matched-pairs signed rank test, P≤0.05.
Results: Overall glycemia is shown in Figure 1. More time was spent in level 1 (54-70 mg·dl-1) (6±5% vs. 4±3%, P=0.05) and level 2 hypoglycemia (&lt;54 mg·dL-1) (3±5% vs. 1±4%, P=0.002) during night vs. day periods. During daytime, more time was spent in level 2 hyperglycemia (&gt;299 mg dL-1) (night 0.2±0.4% vs. day 1.4±2.3%, P=0.02).
Conclusion: Professional cyclists with T1D spent more time in hypoglycemia during the night compared to day-time during intensified training. Long-lasting insulin-sensitizing effects of endurance exercise may suggest a greater need for additional pre-bed carbohydrates and/or insulin dose reductions.

Disclosure
O. Moser: Research Support; Self; Abbott, Dexcom, Inc., Novo Nordisk A/S. M.L. Eckstein: Research Support; Self; Novo Nordisk A/S. O. McCarthy: None. M. Riddell: Advisory Panel; Self; Xeris Pharmaceuticals, Inc. Consultant; Self; Lilly Diabetes. Research Support; Self; Dexcom, Inc., Insulet Corporation, Novo Nordisk Inc., Sanofi. Speaker’s Bureau; Self; Medtronic MiniMed, Inc., OmniPod. Stock/Shareholder; Self; Zucara Therapeutics Inc. F.Y. Fontana: None. K. Skroce: None. L. Festa: None. P.H. Lagrou: None. P. Southerland: Other Relationship; Self; Novo Nordisk Inc. M.P. Christiansen: Research Support; Self; Abbott, Biolinq, Dexcom, Inc., Eli Lilly and Company, Janssen Pharmaceuticals, Inc., Medtronic MiniMed, Inc., Novo Nordisk A/S, Sanofi-Aventis, Xeris Pharmaceuticals, Inc. B.W. Bode: Consultant; Self; ADOCIA, Lexicon Pharmaceuticals, Inc., Novo Nordisk Inc. Research Support; Self; Becton, Dickinson and Company, Dexcom, Inc., Diasome Pharmaceuticals, Inc., Eli Lilly and Company, Eyenuk Inc., Insulet Corporation, National Institutes of Health, Novo Nordisk Inc., Sanofi Research & Development, Senseonics, Xeris Pharmaceuticals, Inc. Speaker’s Bureau; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Janssen Pharmaceuticals, Inc., Novo Nordisk Inc., Sanofi US, Senseonics. Stock/Shareholder; Self; AgaMatrix, Glytec, LLC. C. Stettler: None. S.N. Scott: None. M. Fisher: Advisory Panel; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Mylan, NAPP Pharmaceuticals Limited, Novo Nordisk A/S. Speaker’s Bureau; Self; Eli Lilly and Company, Sanofi. C.A. Hayes: Other Relationship; Self; Novo Nordisk A/S. R.M. Bracken: None.

Funding
Novo Nordisk A/S