Effects of moderate intermittent hypoxia exposure on peripheral insulin sensitivity and substrate metabolism in humans

Recruitment & Eligibility

Status: Completed

Sex: Not specified

Target Recruitment: 15

Inclusion Criteria

Males with overweight/obesity (body mass index >= 28 kg/m2) - insulin resistant (HOMA>=2.2) - Age: 30-65 - Non smoking - A stable bodyweight for at least 3 months (no change in bodyweight: <3kg)

Exclusion Criteria

cardiovascular disease (determined by questionnaire, electrocardiogram (ECG), blood pressure (subjects with moderate to severe hypertension (grade 2 or 3 based on WHO criteria) will be excluded from participation in this study (SBP >160 mmHg, DBP > 100 mmHg)), type 2 diabetes mellitus, cancer, asthma or bronchitis, obstructive sleep apnea (OSAS), liver or kidney malfunction (determined based on ALAT and creatinine levels, respectively), disease with a life expectancy shorter then 5 years (subjects will be asked if they have a disease, which could lead to death within 5yr) diagnosis, abuse of products (alcohol consumption > 15 units/week), smoking, plans to lose weight (subjects will be asked if they have weight loss plans (e.g. to increase their physical activity level or change diet): a positive answer will lead to exclusion) or follow a hypocaloric diet, participation in organized sports activities more than three hours a week, use of high doses of anti-oxidant vitamins (A, C, E, β-carotene; a standard multi-vitamin capsule is permitted if less than 800µg/day Vit A, 60mg/day Vit C, 10mg/day Vit E and 400µg/day β-carotene) or use of any medication that influences glucose metabolism and inflammation

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>- peripheral insulin sensitivity</p><br>

Secondary Outcome Measures

Name	Time	Method
<p>- adipose tissue and skeletal muscle oxygen tension<br /><br>- hepatic insulin sensitivity<br /><br>- body weight<br /><br>- Body Mass Index (BMI)<br /><br>- body composition (DEXA)<br /><br>- adipose tissue blood flow<br /><br>- plasma glucose, insulin, free fatty acids, triacylglycerol, glycerol<br /><br>concentrations<br /><br>- blood pressure<br /><br>- blood oxygen saturation<br /><br>- hunger and satiety<br /><br>- energy expenditure and substrate oxidation<br /><br>- systemic inflammation (e.g. IL-6, leptin, adiponectin, TNFa)<br /><br>- gene expression in adipose tissue and skeletal muscle<br /><br>- fat cell size<br /><br>- adipose tissue and skeletal muscle oxidative capacity<br /><br>- Glucose uptake by adipocytes and myotubes</p><br>