Influence of Exercise Therapy on Insulin Resistance in Patients With Heart Failure

What does the study involve?

A randomized controlled study (n=30) will be performed over a period of 12 weeks. Following study inclusion, baseline measurements will be performed in 1 week. They include:

• a maximal exercise test on a bicycle ergometer to assess exercise tolerance,
• two oral glucose tolerance tests to assess fasting and post-exercise insulin resistance,
• a venous blood sample to determine HbA1c, blood lipids, BNP,
• a muscle strength measurement on a isokinetic dynamometer,
• assessment of body composition via dual energy x-ray absorptiometry,
• cardiac echography,
• questionnaires to assess health-related quality of life,
• a questionnaire (IPAQ) and a pedometer (3 days) to assess physical activity. Following baseline measurements, subjects will be randomized to a control group (CON, n=10) and an exercise intervention group (EX, n=20), matching for gender and reduced/preserved ejection fraction and glucose tolerance. Hereafter, CON will receive usual care and will be advised to maintain their normal lifestyle, EX subjects will be enrolled in a 12-week training program. Following 6 (MID) and 12 (POST) weeks of exercise training including progressive training load adaptations, baseline measurements will be repeated in all patients.

What are the possible benefits and risks of participating?

• Benefits: patients receive a free training program with personal and professional supervision. After completing the study, they receive a report with personal results and evaluation of training effects.
• Risks: the usual risks of exercise tolerance testing and exercise training in a CHF population are limited because training sessions are held in the supervised conditions of the Jessa hospital and because training characteristics are according to guidelines of the European Society of Cardiology. Exposure to x-rays during body composition assessment is very low, almost negligible.