The Potential of a Low Oxygen Environmental Chamber as an Aid to Exercise Training to Improve Metabolic Health
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 14
- 试验地点
- 2
- 主要终点
- Fasting and postprandial plasma glucose concentration
研究概览
简要总结
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 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.
Nonetheless, findings from studies investigating the potential for a hypoxic environment to augment the exercise training response and subsequent metabolic health are equivocal. Notably, there is a paucity of information regarding the optimal combination of exercise variables and hypoxic load (i.e. level of hypoxia) 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 exercise under normoxia (FiO2, 20.9%), moderate (FiO2, 16.5%) and high normobaric hypoxic conditions (FiO2, 14.8%) (60-min cycling session at 90% LT) on 2h OGTT and 24h-glucose level in individuals with overweight. The investigators hypothesize that exercise in combination with hypoxia improves glucose homeostasis in individuals with overweight.
详细描述
In the present randomized, single-blind, cross-over study, participants will be exposed to normobaric 1) normoxia (oxygen level 20.9%), 2) moderate hypoxia (oxygen level 16.5%) and 3) high hypoxia (oxygen level 14.8%) 1) during exercise (60 minutes on a cycle ergometer) at 90% LT. Participants will be randomly assigned to each 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 will cycle for 60 minutes at a 90% lactate threshold (LT), determined by an LT test.
Visit 1 (Screening and consent):
Introduction to the research team and tour of the facility. Complete and sign the Adult Pre-Exercise Screening System form. Complete and sign the consent information form.
Visit 2:
Body composition screening using bioimpedance analysis (Inbody 770, Cerritos, CA, USA) Blood pressure screening. Lactate threshold test-participants will be riding a Velotron cycle ergometer (Racermate, Seattle, USA) with an initial load of 50 Watts. The load increased progressively in 15 Watts increments every 4 minutes, with participants maintaining a constant pedal frequency (cadence ~90 rpm) until reaching LT.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Single (Participant)
入排标准
- 年龄范围
- 20 Years 至 40 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •BMI is between 25-29 kg/m²
- •Sedentary (physical activity <150 min/week)
- •No known heart or metabolic diseases (such as Type 2 diabetes)
- •Not currently taking any prescribed medication
- •No reported musculoskeletal injuries recently
- •Not exposed to hypoxia >1000 m prior to the study
排除标准
- •Impaired glucose tolerance (2 hour glucose: >7.8 - 11.1 mmol/L)
- •Type 2 diabetes mellitus
- •Obstructive sleep apnea
- •Chronic obstructive pulmonary disease
结局指标
主要结局
Fasting and postprandial plasma glucose concentration
时间窗: Change of fasting and postprandial plasma glucose concentrations (mmol/L) compared to moderate intensity exercise under normoxia (20.9% oxygen) at immediately after exercise (2 hour oral glucose tolerance test).
Change of plasma glucose concentration immediately post-exercise under hypoxia (14.8-16.5% oxygen) compared to normoxia.
Fasting and postprandial plasma insulin concentration
时间窗: Change of fasting and postprandial plasma insulin concentrations (mU/L) compared to moderate intensity exercise under normoxia (20.9% oxygen) at immediately after exercise (2 hour oral glucose tolerance test).
Change of plasma insulin concentration immediately post-exercise under hypoxia (14.8-16.5% oxygen) compared to normoxia.
次要结局
- Average 24 hours glucose concentration(Change of average glucose concentration compared to moderate intensity exercise under normoxia (20.9% oxygen) up to 24 hour after exercise.)
- Circulating concentration of fibroblast growth factor 21 (FGF-21)(Change of concentrations of FGF-21 compared to moderate intensity exercise under normoxia (20.9% oxygen) immediately after exercise and at 24 hours after exercise.)
- Circulating concentration of apelin(Change of concentrations of apelin compared to moderate intensity exercise under normoxia (20.9% oxygen)immediately after exercise and at 24 hours after exercise.)