Effects of Normobaric Hypoxia and Different Exercise Modes on Blood Glucose Regulation in Overweight Adults
Condition: Overweight; Healthy; Physical Inactivity
MeSH terms: Overweight; Hypoxia
Study type: Interventional

Summary: 
      Obesity is a major global health issue and a primary risk factor for metabolic-related
      disorders. While physical inactivity is one of the main contributors to obesity, it is a
      modifiable risk factor with exercise training as an established, non-pharmacological
      treatment to prevent the onset of metabolic-related disorders, including obesity. Exposure to
      low-oxygen availability (hypoxia) via normobaric hypoxia (simulated altitude via reduced
      inspired oxygen fraction), termed hypoxic conditioning, in combination with exercise has been
      increasingly shown in the last decade to enhance blood glucose regulation and decrease body
      mass index, providing a feasible strategy to treat obesity.

      However, findings from studies investigating the potential for hypoxia to augment the
      exercise training response and subsequent metabolic health are equivocal. Notably, there is a
      lack of information regarding the optimal combination of exercise variables and hypoxic
      severity to enable an individualized and safe practice of exercising in a hypoxic
      environment.

      In the present randomized, single-blind, cross-over study, the investigators will investigate
      the effects of single-bout of different exercise modes under moderate hypoxia (FiO2, 16.5%).

      The investigators hypothesize that all exercises combined with hypoxia improve glucose
      homeostasis in overweight individuals.
    

Detailed description: 
      In the present randomized, single-blind, cross-over study, participants will be exposed to
      moderate hypoxia (oxygen level 16.5%) during three different exercises (low-intensity
      cycling, sprint interval and functional exercises). Participants will be randomly assigned to
      each exercise condition (computer-generated randomization plan), separated by a washout
      period (5-7 days). To accomplish this, participants will exercise in an environmental chamber
      in which oxygen concentration of the ambient air and, as such, oxygen levels can be closely
      controlled and monitored.

      Participants are required to attend the laboratory 8 times. These visits are including
      pre-exercise screening, baseline blood sampling, body composition screening and exercise in
      altitude conditions.
    

Intervention name(s): Low-moderate intensity exercise; Sprint interval training; Functional exercise; Control
Intervention type(s): Other; Other; Other; Other
Intervention description(s): The participants will perform low-intensity cycling exercise at 90% lactate threshold under moderate hypoxia; The participants will perform sprint interval cycling exercise at a load of 7.5% bodyweight under moderate hypoxia.; The participants will perform bodyweight exercises under moderate hypoxia.; No exercise will be performed.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Other