Clinical Trials Logo

Clinical Trial Summary

The obesity epidemic calls for new therapeutic opportunities to prevent and treat obesity and its comorbidities amongst which are insulin resistance and cardiovascular diseases. Recent evidence suggests that tissue oxygenation plays an important role in cardiometabolic health. Remarkably, individuals residing at high altitude (hypobaric hypoxia) are less prone to develop type 2 diabetes mellitus as compared to individuals living at sea-level (normobaric normoxia). Furthermore, there is evidence to suggest that normobaric hypoxia exposure may improve glucose homeostasis and insulin sensitivity in both rodents and humans. The level of physical activity is an important determinant of insulin sensitivity and glucose homeostasis. It is well established that performing physical activity improves glucose uptake in the short term, and glycemic control in the long term. Interestingly, recent studies have demonstrated that an acute bout of exercise under hypoxic conditions (inhalation of air containing less oxygen) may lead to a more pronounced improvement in plasma glucose concentrations and/or insulin sensitivity as compared to normoxic exercise. However, the effects of repeated hypoxic exercise bouts on glucose profile throughout the day (i.e. 24h continuous glucose monitoring) remain elusive. In the present randomized, placebo-controlled, single-blind, cross-over study study, the investigators will investigate the effects of exercise under mild normobaric hypoxic conditions (FiO2, 15%) for 4 consecutive days (2 x 30-min cycling session at 50% WMAX) on postprandial substrate metabolism and 24h-glucose level in overweight/obese subjects with impaired glucose tolerance. The investigators hypothesize that 4 consecutive days of exposure to mild hypoxia while performing moderate intensity exercise improves glucose homeostasis in overweight and obese individuals with impaired glucose homeostasis.


Clinical Trial Description

In the present randomized, single-blind, placebo-controlled cross-over study, subjects will be exposed to normobaric 1) mild hypoxia (oxygen level: 15%) and 2) normoxia (oxygen level: 21%) during exercise (2 x 30min/day on a cycle ergometer) of the same relative exercise intensity (equal to 50%WMAX under normoxic conditions) for 4 consecutive days. Subjects will be randomly assigned to each condition (computer-generated randomization plan; block size, n=4), separated by a washout period (3-6 weeks). To accomplish this, subjects will exercise in an oxygen chamber in which oxygen concentration of the ambient air and, as such, oxygen levels can be tightly controlled and monitored. Subjects will cycle two times a day for 30 minutes at 50% WMAX, determined by an incremental workload test. Since we will allow 5-10 min for subjects to get ready to start the 30-min exercise session, and take into account a 5-min cooling down period before leaving the hypoxic room again, subjects will be in the room for 45 min for each session. After initial screening, subjects are asked to visit the university for two periods of 5 consecutive days each with a washout period of 3-6 weeks. During the first 4 days (time investment: 4.5 hours/day), subjects will be undergoing the exercise regimen, as described above. - At day 1, on the first morning of each regimen, a glucose sensor (Enlite Glucose Sensor MiniMed; Medtronic). The sensor will be inserted subcutaneously, will be inserted subcutaneously, at 5 cm from the umbilicus, on the right side of the abdomen, and will be connected to a continuous glucose monitor (iPro2 Professional CGM MiniMed; Medtronic, Northridge, CA, USA). The sensor will remain inserted throughout the study (days 1-5). Furthermore, a physical activity monitor (ActivPAL3 micro monitor) will be applied at the same moment, to monitor physical activity of participants. At the end of day 5, the glucose sensor, and the physical activity monitor will be removed. - At days 1-5 (time investment: 4.5 hours), fasting blood samples will be collected to determine plasma metabolites and inflammatory markers, and blood pressure and body weight will be monitored. - At day 5 (time investment: 8 hours), a mixed liquid meal challenge will be performed to determine fasting and postprandial metabolite concentrations, and substrate oxidation (using indirect calorimetry). A skeletal muscle biopsy (m. vastus lateralis) will be collected under fasting conditions. Moreover, HOMA-IR will be used to estimate insulin resistance, using fasting plasma glucose and insulin values measured on the day after completion of the 4 day regimen. After initial screening, the assessment of basal metabolic rate (BMR) and the incremental workload test (to determine the maximal workload, WMAX), subjects will have to invest approximately 52 hours. ;


Study Design


Related Conditions & MeSH terms


NCT number NCT04280991
Study type Interventional
Source Maastricht University Medical Center
Contact
Status Completed
Phase N/A
Start date July 22, 2019
Completion date December 18, 2020

See also
  Status Clinical Trial Phase
Recruiting NCT04101669 - EndoBarrier System Pivotal Trial(Rev E v2) N/A
Recruiting NCT04243317 - Feasibility of a Sleep Improvement Intervention for Weight Loss and Its Maintenance in Sleep Impaired Obese Adults N/A
Terminated NCT03772886 - Reducing Cesarean Delivery Rate in Obese Patients Using the Peanut Ball N/A
Completed NCT03640442 - Modified Ramped Position for Intubation of Obese Females. N/A
Completed NCT04506996 - Monday-Focused Tailored Rapid Interactive Mobile Messaging for Weight Management 2 N/A
Recruiting NCT06019832 - Analysis of Stem and Non-Stem Tibial Component N/A
Active, not recruiting NCT05891834 - Study of INV-202 in Patients With Obesity and Metabolic Syndrome Phase 2
Active, not recruiting NCT05275959 - Beijing (Peking)---Myopia and Obesity Comorbidity Intervention (BMOCI) N/A
Recruiting NCT04575194 - Study of the Cardiometabolic Effects of Obesity Pharmacotherapy Phase 4
Completed NCT04513769 - Nutritious Eating With Soul at Rare Variety Cafe N/A
Withdrawn NCT03042897 - Exercise and Diet Intervention in Promoting Weight Loss in Obese Patients With Stage I Endometrial Cancer N/A
Completed NCT03644524 - Heat Therapy and Cardiometabolic Health in Obese Women N/A
Recruiting NCT05917873 - Metabolic Effects of Four-week Lactate-ketone Ester Supplementation N/A
Active, not recruiting NCT04353258 - Research Intervention to Support Healthy Eating and Exercise N/A
Completed NCT04507867 - Effect of a NSS to Reduce Complications in Patients With Covid-19 and Comorbidities in Stage III N/A
Recruiting NCT03227575 - Effects of Brisk Walking and Regular Intensity Exercise Interventions on Glycemic Control N/A
Completed NCT01870947 - Assisted Exercise in Obese Endometrial Cancer Patients N/A
Recruiting NCT05972564 - The Effect of SGLT2 Inhibition on Adipose Inflammation and Endothelial Function Phase 1/Phase 2
Recruiting NCT06007404 - Understanding Metabolism and Inflammation Risks for Diabetes in Adolescents
Recruiting NCT05371496 - Cardiac and Metabolic Effects of Semaglutide in Heart Failure With Preserved Ejection Fraction Phase 2