High-Intensity Exercise and Endothelial Function in Type 1 Diabetes(HIIT-T1D)

Hospital de Clinicas de Porto Alegre

Status: Completed

Conditions: Type 1 Diabetes Mellitus; Endothelial Dysfunction

Treatments: Other: Non-exercise; Behavioral: Moderate Continuous Exercise Training; Behavioral: High Intensity Interval Training

Study type: Interventional

Funder types: Other

Identifiers

NCT03451201

150564

Details and patient eligibility

About

To study the effect of 8 week high-intensity interval training (HIIT) compared with moderate intensity (MCT) interval training and sedentary patients(CON) with type 1 diabetes. Adult T1DM patients without known complications are randomised in blocks into these 3 groups according to their baseline flow mediated dilation (FMD). After 8 week exercise training, the main outcome, FMD, is re-evaluated. Additional variables such as VO2 peak for cardiovascular fitness, oxidative stress and endothelial independent vasodilation to study vascular rigidity are also evaluated.

Full description

In a randomized controlled open trial, 36 adult type 1 diabetes mellitus (T1DM) patients without known complications were randomized into 3 groups: HIIT n=12; MCT n=12 and a sedentary control group (CON) n=12. Total sample size was calculated to a power of 80% alha 0.05 and a difference in mean FMD of 2%. Before randomisation, flow mediated dilation (FMD) and maximal exercise capacity (VO2 peak)is determined. Block Randomisation based on FMD rank values are done to equalize baseline FMD. Exercise sessions are performed in cycle ergometers during 40 minutes, 3 times a week, along 8 weeks. HIIT protocol, intensity vary from 50 to 85% of the maximum heart rate (HRmax), while in MCT, HR remained stable at 50% HRmax. Endothelial function was measured by flow mediated dilation (FMD) for endothelium-dependent vasodilation (EDVD) and smooth-muscle function was measured by nitroglycerine mediated dilation (endothelium independent vascular dilation) - (EIVD). Peak oxygen consumption (VO2peak) and oxidative stress markers were determined before and after the training period. ED was defined as an increase of less than 8% in vascular diameter after cuff release.

Enrollment: 36 patients

Sex: All

Ages: 18 to 40 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

T1DM

• Physically inactive or not involved in exercise training programs in the previous 6 months
• Interested in starting an exercise training program.

Exclusion criteria

• Smokers,
• Pregnancy
• Co-morbidities not related to diabetes
• Drugs other than insulin
• Loss of renal function (serum creatinine above 1.5 mg/dl),
• Moderate to severe retinopathy or blindness,
• Suspected or confirmed coronary artery disease,
• Severe peripheral neuropathy
• Foot ulcers or history of previous foot ulcer
• Suspected or confirmed clinical autonomic neuropathy.

Trial design

Primary purpose: Supportive Care

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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36 participants in 3 patient groups

High Intensity Interval Training

Experimental group

Description:

High Intensity Interval Exercise Training in cycle ergometer 3 times a week for 8 weeks

Treatment:

Behavioral: High Intensity Interval Training

Moderate Continuous Exercise Training

Active Comparator group

Description:

Moderate Continuous Interval Training

Treatment:

Behavioral: Moderate Continuous Exercise Training

Non-exercise

Other group

Description:

Sedentary Type 1 Diabetes Controls.

Treatment:

Other: Non-exercise