Type 1 diabetes (T1D) is associated with increased risk of poor cardiometabolic health. Regular exercise is recommended for optimal management of comorbidities in T1D. Unique barriers to exercise exist for T1D, including fear of hypoglycemia, unpredictable glycemic excursions with exercise, and inadequate knowledge about exercise. Unlike traditional moderate intensity continuous training (MICT) which requires extended periods of time, high intensity interval training (HIIT) requires minimal time (~10 minutes of exercise per session), with the potential to rapidly stimulate mitochondrial biogenesis and metabolism. The extent to which these exercise strategies alter metabolomic signatures of carbohydrate, fat, and amino acid metabolism in T1D is unknown. The overall goal of the proposed project is to identify the acute metabolic effects and physiological modifiers of HIIT compared to MICT and control (CON) using metabolomic profiling and cardiometabolic assessments in 14 adults with T1D. Using a randomized cross-over approach, the primary aim is to compare the metabolomics response immediately post, 1 hr post, and glycemic control through 48 hrs after HIIT, compared to MICT matched for total energy expenditure, versus a no exercise CON. An additional aim will be to characterize the influence of biological sex and physiological outcomes (i.e. body composition, lean mass, visceral fat) on the metabolomics profile of these subjects. Outcomes from the present study, with existing data from our team, will lay the foundation for a larger diet and exercise lifestyle intervention that will ultimately lead to changes in clinical practice to co-manage glycemia and cardiometabolic comorbidities.

Inclusion Criteria:

• Clinical diagnosis of presumed autoimmune T1D, receiving daily insulin
• Last hemoglobin A1c <9%
• 18-51 years
• Duration of T1D: ≥ 1 year
• Body mass index (BMI) <30 kg/m^2
• Generally healthy, with no conditions that could influence the outcome of the trial, and in the judgement of the investigators is a good candidate for the study, based on a review of health history

Exclusion Criteria:

• Physician diagnosis of active diabetic retinopathy that could be worsened by exercise
• Physician diagnosis of peripheral neuropathy with insensate feet
• Physician diagnosis of autonomic neuropathy
• Medications: beta-blockers, agents that affect hepatic glucose production such as beta adrenergic agonists, xanthine derivatives; any hypoglycemic agent other than insulin.
• Severe hypoglycemic event defined as the individual requiring a third party of hospitalization in the last 6 months
• Diabetic ketoacidosis in the last 6 months
• Has a closed-loop pump and not willing to use manual mode
• Physician diagnosis of cardiovascular disease that would affect exercise tolerance
• Currently doing HIIT
• Severely impaired hearing or speech
• Pregnancy

Deidentified individual data that supports the results will be shared beginning 12 to 24 months following publication provided the investigator who proposes to use the data has approval from an Institutional Review Board (IRB), Independent Ethics Committee (IEC), or Research Ethics Board (REB), as applicable, and executes a data use/sharing agreement with UNC.

Beginning 1 year and ending 2 years following article publication

IRB, IEC, or REB approval, as applicable, and an executed data use/sharing agreement with UNC.