Fasted Exercise Training in Type 1 Diabetes (FED-T1D) (FED-T1D)

Exercise Training Before (Fasted) Versus After (Fed) Breakfast in Type 1 Diabetes

This study compares aerobic exercise training performed before breakfast (i.e., in the fasted state) to similar training performed after breakfast in people with type 1 diabetes. Training will take place over 12 weeks.

Study Overview

• Status: Recruiting
• Conditions: Diabetes Mellitus, Type 1
• Intervention / Treatment: Behavioral: Fasted Exercise; Behavioral: Postprandial Exercise

Detailed Description

People with type 1 diabetes (PwT1D) are encouraged to increase their physical activity (PA). Increasing the amount of PA can be difficult, especially for PwT1D who experience barriers to exercise. Therefore, simply recommending that PwT1D preform more exercise may not be the most effective prescription in the long term. Recent short-term studies have s suggest that exercise performed before eating (fasted) causes blood sugars to decrease less or even increase, compared exercise performed after a meal, which usually causes blood sugar to decrease. To date, no long-term study has compared the effects of exercise performed with or without eating beforehand in people with T1D.

This study will compare the effects of 12 weeks of exercise before breakfast compared to 12 weeks of exercise after breakfast. It is expected that exercise before breakfast (i.e., in the fasted state) will lead to larger reductions in overall insulin dose, without the addition of more exercise.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Normand Boule, PhD; Phone Number: 780-492-4695; Email: nboule@ualberta.ca
• Study Contact Backup: Name: Reid McClure, MSc; Phone Number: 780-492-8079; Email: rmcclur1@ualberta.ca

Study Locations

• Canada
  • Alberta
    • Edmonton, Alberta, Canada, T6G 2E1
      • Recruiting
      • University of Alberta
      • Contact: Normand Boule, PhD; Phone Number: 780-492-4695; Email: nboule@ualberta.ca
      • Contact: Reid McClure, MSc; Phone Number: 780-492-8079; Email: rmcclur1@ualberta.ca
      • Principal Investigator: Normand Boule, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Clinical diagnosis of type 1 diabetes for 5 or more years.
2. Treatment using an insulin pump with no change in treatment modality for > 2 continuous months and willing to share CGM data with the research team. Insulin delivery can be managed using either manual open-loop system (non-AID) or a hybrid closed loop (AID) systems.
3. Using rapid (e.g., Aspart, Lispro or Glulisine) or ultra-rapid (e.g., FiAsp) acting insulin analogs.
4. HbA1c 7.0-9.9%.
5. Have BMI of 25 kg/m2 or above

6. Have waist circumference associated with central obesity/metabolic syndrome as per Diabetes Canada definition

   • 94cm for males of European, Sub-Saharan African, Eastern Mediterranean and Middle Eastern descent
   • 90cm for males of South Asian, Chinese, Japanese, South and Central American descent
   • 80cm for females
7. No history of stroke, myocardial infarction, or coronary artery disease
8. Not wearing implantable device such as a pacemaker, neurostimulators, aneurysm clips, metal fragments, epicardial electrodes, cochlear implants, magnetic ocular implants, penile implants, magnetic tissue expander, some types of breast implants, magnetic orthopedic implants, magnetic dental implants, hearing Aids, intravascular implants, for example VCI filters, coils, stents, cardiac septum implants, ventricular bypass devices.
9. Use a CGM in routine diabetes management.

Exclusion Criteria:

1. Major complication within the previous 3 months (e.g., severe hypoglycemia requiring assistance, diabetic ketoacidosis, or cardiovascular event).
2. Restriction in aerobic or resistance exercise due to significant diabetes complications (e.g., severe peripheral neuropathy, active proliferative retinopathy, etc.) or other type of limitations (e.g., orthopedic, severe arthritis, etc.).
3. Uncontrolled hypertension (e.g., blood pressure >160 mmHg systolic or >100 mmHg diastolic).
4. Implanted device, material, or having a condition contraindicated to MRI.
5. Ongoing pregnancy or breastfeeding.
6. Inability to give consent.
7. Use of an injection-based insulin therapy (ex. multiple daily injections or combined pump and injection-based delivery).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Fasted Exercise; Exercise training will be performed in the fasted state (i.e., before breakfast).	Behavioral: Fasted Exercise; Participants will complete three sessions of combined resistance-aerobic exercise per week. Sessions will always start with resistance training followed by aerobic training, and will increase in duration throughout the intervention period, so that by the final three weeks of the intervention, all participants accumulate 150 minutes per week of moderate intensity aerobic exercise and 75 minutes of resistance exercise per week. Participants will complete three distinct resistance exercise sessions per week, which will increase in load, but decrease in repetition range throughout the trial. The aerobic component of the exercise sessions will increase in duration from 35 to 50 minutes per session. Participants will walk on a treadmill at a speed and incline that corresponds to 70-80% of ventilatory threshold.
Active Comparator: Postprandial Exercise; Exercise will be performed in the postprandial period (i.e., after breakfast)	Behavioral: Postprandial Exercise; Participants will complete three sessions of combined resistance-aerobic exercise per week. Sessions will always start with resistance training followed by aerobic training, and will increase in duration throughout the intervention period, so that by the final three weeks of the intervention, all participants accumulate 150 minutes per week of moderate intensity aerobic exercise and 75 minutes of resistance exercise per week. Participants will complete three distinct resistance exercise sessions per week, which will increase in load, but decrease in repetition range throughout the trial. The aerobic component of the exercise sessions will increase in duration from 35 to 50 minutes per session. Participants will walk on a treadmill at a speed and incline that corresponds to 70-80% of ventilatory threshold.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Daily insulin dose (units/kg/day)	Total daily insulin dose (including basal and bolus insulin) will be measured over 7 consecutive days.	From enrolment to the end of the exercise intervention at week 12.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Continuous glucose monitoring	24-hour mean glucose (mmol/L) as measured by continuous glucose monitors.	From enrolment to the end of the exercise intervention at week 12.
Continuous glucose monitoring	Time in range (%) as measured by continuous glucose monitors.	From enrolment to the end of the exercise intervention at week 12.
Magnetic resonance imaging (MRI) volumes	MRI derived volumes (e.g., muscle fat, hepatic fat, pancreatic fat, subcutaneous fat, visceral fat)	From enrolment to the end of the exercise intervention at week 12.
Basal and bolus insulin dose (units/kg/day)	Basal insulin dose (units/kg/day), bolus insulin dose (units/kg/day), and basal to bolus ratio	From enrolment to the end of the exercise intervention at week 12.
Bioelectrical impedance (BIA) in kilograms	BIA body composition outcomes (e.g., fat mass, fat free mass, total body water), all measured in kilograms	From enrolment to the end of the exercise intervention at week 12.
Glycated haemoglobin (%)	Hlycated hemoglobine (also known as HbA1c) expressed as a percentage.	From enrolment to the end of the exercise intervention at week 12.
Concentrations of Fasting glucose	Plasma glucose measured after an overnight fast	From enrolment to the end of the exercise intervention at week 12.
Concentrations of Fasting insulin	Plasma insulin measured after an overnight fast	From enrolment to the end of the exercise intervention at week 12.
Concentrations of Fasting lipids	Plasma total cholesterol, HDL-Cholesterol, LDL-Cholesterol and Triglycerides measured after an overnight fast	From enrolment to the end of the exercise intervention at week 12.
Aerobic fitness	Exercise test to determine ventilatory threshold	From enrolment to the end of the exercise intervention at week 12.
Body weight (kilograms)	Weight will be measured in kilograms	From enrolment to the end of the exercise intervention at week 12.
Height (centimeters)	Standing height	From enrolment to the end of the exercise intervention at week 12.
Waist circumference (centimeters)	Waist circumference (between 12 rib and iliac crest) measures in centimeters	From enrolment to the end of the exercise intervention at week 12.
Hip circumference (centimeters)	Hip circumference (between 12 rib and iliac crest) measures in centimeters	From enrolment to the end of the exercise intervention at week 12.
Physical Activity in minutes per day	Accelerometer measured active time (min/day), sedentary time (min/day)	From enrolment to the end of the exercise intervention at week 12.
Food logs (kilocalories)	Food logs will be completed for three days (two weekday and one weekend) for estimation of macronutrient intake and total energy intake. Each of these will be expressed as kilocalories (i.e., kcal).	From enrolment to the end of the exercise intervention at week 12.
Feasibility (rates expressed as percentage of the total sample)	Feasibility will include recruitment rate, and dropout rate. Each rate will be reported as the percentage of the total sample.	From enrolment to the end of the exercise intervention at week 12.
Feasibility (rates expressed as percentage of the total number of sessions)	Feasibility will also include exercise adherence. Adherence will be reported as the percentage of the prescribed exercise sessions that were completed).	From enrolment to the end of the exercise intervention at week 12.
Feasibility (barriers)	Barriers will bve assessed using the "Barriers to Physical Activity in Type 1 Diabetes" (BAPAD-1) scale. This is a 11-item scale with 7-point Likert-type questions (i.e., each question has a minimum of 1 and a maximum of 7). The maximum score is therefore 77 and minimum score 11. A higher score indicates greater barriers.	From enrolment to the end of the exercise intervention at week 12.

Collaborators and Investigators

• Sponsor: University of Alberta
• Collaborators: Alberta Diabetes Institute
• Investigators: Principal Investigator: Normand G Boule, PhD, University of Alberta

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2025
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): April 1, 2027

Study Registration Dates

• First Submitted: November 13, 2024
• First Submitted That Met QC Criteria: December 23, 2024
• First Posted (Actual): December 27, 2024

Study Record Updates

• Last Update Posted (Actual): May 8, 2026
• Last Update Submitted That Met QC Criteria: May 7, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Exercise; Continuous glucose monitoring; Liver fat; Muscle fat; total daily insulin dose
• Additional Relevant MeSH Terms: Endocrine System Diseases; Metabolic Diseases; Autoimmune Diseases; Immune System Diseases; Digestive System Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Liver Diseases; Behavior; Nutritional and Metabolic Diseases; Fatty Liver; Diabetes Mellitus, Type 1; Motor Activity
• Other Study ID Numbers: Pro00140125; RES0067483 (Other Identifier: University of Alberta)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: We plan to share all of the data related to study outcomes pm am open access website through the University of Alberta "Education and Research Archive" (ERA). Individual participant characteristics that could be used to identify participants (age, sex, height, weight) will not be be placed on ERA.
• IPD Sharing Time Frame: The data will become available one year after the completion of the trial.
• IPD Sharing Access Criteria: The outcome data will be open access through the University of Alberta "Education and Research Archive" (ERA) website. Other participant characteristics will be available as meta-data.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No