Impact of Obesity on Microvascular Insulin Action and Cardiorespiratory Fitness in Type 1 Diabetes
Impact of Obesity on Microvascular Insulin Action and Cardiorespiratory Fitness in Type 1 Diabetes (
Who can join
As published by the study on ClinicalTrials.gov. "Not stated" means the study hasn't said — ask the study team.
- Age
- 21 Years to 50 Years
- Sex
- All sexes
- Healthy volunteers
- Accepted
- Compensation
- Not stated
Other requirements are listed under Eligibility below. Only the study team can confirm whether you can join.
What to expect
No one can promise a trial will help you personally — that is what the research is trying to find out.
What participation involves
Not stated in the study description — ask the study team about visits and procedures.
- Compensation
- Not stated
- Study-related exams and procedures are typically provided at no cost. This is how many trials work in general — confirm the details for this study with the study team.
- Participants are monitored closely by the research team throughout the study.
- Some participants may receive access to an investigational treatment, which is still being studied.
- Your participation helps researchers learn whether this approach could help future patients.
About this study
In plain language
This study looks at whether insulin resistance—when muscles respond less well to insulin—and extra body weight are linked to lower heart and lung fitness in people with type 1 diabetes. It compares adults with type 1 diabetes with healthy adults, before and after an exercise program with short bursts of hard exercise.
The purpose of this study is: * To see if insulin resistance (how sensitive your muscle tissue is to insulin) is associated with lower cardio fitness in people with Type 1 diabetes compared to healthy controls, before and after a High Intensity Interval Training (HIIT) exercise program. * To see if being overweight and having Type 1 diabetes is associated with lower cardio fitness compared to overweight healthy controls, before and after a HIIT exercise program.
Compensation is read from the study's own description and may be missing — always confirm with the study team.
Eligibility
Who can join
- Adults ages 21 to 50.
- If you have type 1 diabetes, you must have had it for at least 5 years, use several daily insulin shots or an insulin pump, and have an HbA1c of 8.5% or less. HbA1c measures average blood sugar.
- BMI, a measure of weight compared to height, must be 19–27 for groups without obesity or 30–40 for groups with obesity. For Asian Americans in the obesity groups, the range is 27.5–37.5.
- Use of medicines other than insulin must be stable for more than 6 months. Medicines containing estrogen or progesterone must be stopped at least 3 months before the study. IUDs, birth control devices placed in the womb, may be continued.
Who can't join
- An illness other than type 1 diabetes or obesity; a history of serious disease or cancer; or gastroparesis, when the stomach empties too slowly.
- Diabetes-related blood vessel damage, diabetic ketoacidosis (dangerous acid buildup in the blood) in the past 24 months, or a history of not noticing low blood sugar.
- Recently doing more than 20 minutes of moderate or hard exercise twice a week.
- Smoking now or having quit less than 5 years ago.
- Triglycerides, a type of blood fat, above 400 mg/dL, or a blood oxygen reading below 90%.
- Current use of medicines that affect blood vessels, such as certain blood pressure medicines or water pills; or birth control pills in the past 3 months.
- Pregnant, based on a positive pregnancy test, or breastfeeding.
- A muscle, bone, or joint condition that prevents exercise testing or training.
Simplified for readability. The official criteria below are what the study team uses.
Official eligibility criteria
Inclusion Criteria: * • Male or female ≥21 and ≤50 years old * For persons with T1D: Disease duration ≥ 5 years and HbA1c ≤ 8.5% on multiple daily insulin injection or insulin pump * Body mass index: ≥19 and ≤27 kg/m2 for control and T1D, ≥30 and ≤40 kg/m2 (27.5 to 37.5 for Asian Americans) for obesity and T1D + obesity. BMI is limited to ≤40 kg/m2 (37.5 for Asian Americans) for easier vascular access and cardiac imaging. * Stable use of non-insulin medications for over 6 months other than estrogen/progesterone containing medications which must be discontinued at least 3 months prior to the study (intrauterine devices may be continued due to limited systemic absorption) Exclusion Criteria: * • Acute or chronic disease other than T1D or obesity * History of microvascular or macrovascular diabetes complications * History of diabetic ketoacidosis in the past 24 months * History of hypoglycemia unawareness * Recently active (\>20 min of moderate/high intensity exercise, 2 times/week) * Subjects who are smokers or who have quit smoking \<5 years * Subjects with hypertriglyceridemia (\>400 mg/dl) * Current use of vasoactive medications (i.e. calcium channel blockers, angiotensin-converting enzyme or renin inhibitors, angiotensin-receptor blockers, nitrates, alpha- or beta-blockers, or diuretics). * Females taking oral contraceptives in the past 3 months * Subjects with a history of significant metabolic, cardiac, cerebrovascular, hematological, pulmonary, gastrointestinal, liver, renal, or endocrine disease or malignancy * Pregnant (as evidenced by positive pregnancy test) or nursing women * Musculoskeletal condition preventing participation in exercise testing or exercise training * History of gastroparesis * Pulse oximetry \<90%
Study sites (1)
VA
- University of Virginia · Charlottesville, VA 22908Zhenqi Liu, MD · Study contact · 434-924-5247 · zl3e@UVAhealth.orgLee Hartline, MEd · Study contact · 434-924-5247 · lmh9d@virginia.eduZhenqi Liu, MD · Principal investigatorMore trials in Charlottesville