Objective: Consensus guidelines may help people with type 1 diabetes (T1D) improve exercise glucose outcomes. Glucose outcomes were evaluated in real-world exercise when participants did or did not follow guidelines.

Methods: In a 4-week observational study, continuous glucose, insulin and nutrient data were collected from 561 adults with T1D. Participants completed study and personal exercise. Glucose outcomes were compared when participants followed versus did not follow exercise guidelines for open-loop (OL) and automated insulin delivery (AID).

Results: Guidelines requiring behavior modification (e.g. reduce meal insulin before exercise) were rarely followed while guidelines not requiring modification were often followed (Fig). The guideline recommending reduced meal insulin before exercise was associated with lower % time <70 mg/dL (T<70) during exercise (-2.2%, P=0.02) for OL but was not significant for AID (-1.5%, P=0.22). Compared to exercise with low glucose (<70 mg/dL) in prior 24 hours, sessions without recent low glucose had lower T<70 during exercise (-1.2%, P<0.001). The AID guideline for no carbs before exercise if CGM is flat and increasing was not associated with improved outcomes.

Conclusions: Real-world evidence suggests OL participants who reduced meal insulin prior to exercise and did not have low glucose in the prior 24 hours had less time below range.

Disclosure

P.G. Jacobs: Advisory Panel; Eli Lilly and Company. Research Support; Dexcom, Inc. Stock/Shareholder; Pacific Diabetes Technologies. C. Marak: None. P. Calhoun: None. R.L. Gal: None. M.C. Riddell: Consultant; Eli Lilly and Company. Speaker's Bureau; Novo Nordisk. Advisory Panel; Supersapiens. Consultant; Dexcom, Inc. Speaker's Bureau; Sanofi. Advisory Panel; Zealand Pharma A/S. Speaker's Bureau; Dexcom, Inc. Stock/Shareholder; Zucara Therapeutics. J. Castle: Employee; Dexcom, Inc.

Funding

The Leona M. and Harry B. Helmsley Charitable Trust

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