DIY insulin systems under the microscope: safe for exercise?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Males and females aged ≥ 18 years old. 2. Clinical diagnosis of type 1 diabetes or latent autoimmune diabetes in adults (LADA) for at least one year. (The diagnosis of type 1 diabetes is based on the investigator's judgment; C peptide level and antibody determinations are not needed.) 3. Using automated insulin delivery systems (Commercial or DIY) for at least 3 months. 4. Willing to share CGM data and insulin pump data with the research team. This access will be limited to the study period. 5. Exercising at least twice weekly (Questionnaire assessment MAQ) or willing to exercise at least twice weekly during the study period. 6. Willing to share physical activity tracker data with the research team and if applicable, data about the menstrual cycle. Exclusion Criteria: 1. Do not understand French or English 2. Anticipated therapeutic change (including change of insulin type \[switching to biosimilar is acceptable\] and/or type of CGM sensor) between admission and end of the study. 3. Anticipated need to use acetaminophen (dose above 1g every 6 hours) or vitamin C (dose above 500mg DIE) between admission and end of the study. 4. Pregnancy (ongoing or current attempt to become pregnant). 5. Breastfeeding. 6. Uncontrolled thyroid disease (recent less than 5 months TSH should be in target range and treatment stable for at least 6 weeks). 7. Severe hypoglycemic episode within two weeks of screening. 8. Severe hyperglycemic episodes requiring hospitalization in the last 3 months 9. Current use of glucocorticoid medication (except low stable dose and inhaled steroids and stable adrenal insufficiency treatment e.g., Cortef®). 10. Current use of adjunct therapy such as SGLT-2 inhibitors or GLP\_1 receptor analog unless at a stable dose for at least 3 months, without anticipated change during the study and appropriate ketone testing is performed in case of off-label SGLT2 usage. 11. Anticipated radiologic examination incompatible with CGM wear for more than 10 days between admission and end of the study (e.g., repeated MRI). 12. Physically inactive participants (see inclusion criteria #5). 13. People with professional activities involving night shifts, as it may influence glycemic profiles differently compared to people working days and sleeping nights. 14. In the opinion of the investigator, a participant who is unable or unwilling to complete the study (e.g., recent injury, foot wound, etc.).