The Potential of a Low Oxygen Environmental Chamber as an Aid to Exercise Training to Improve Metabolic Health

NCT05577429 | Completed DMC

• 2 other identifiers: 20225950-9155ISNRG003/2020
• Study Type: interventional
• Target: 14
• Locations: 1 country
• Sites: 1

Brief 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 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.

Conditions

Overweight; Physical Inactivity; Healthy

Keywords

Hypoxia; Overweight; Glucose tolerance; Exercise

Outcome Measures

Primary Outcomes (2)

• Fasting and postprandial plasma glucose concentration

  Change of plasma glucose concentration immediately post-exercise under hypoxia (14.8-16.5% oxygen) compared to normoxia.

  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).

• Fasting and postprandial plasma insulin concentration

  Change of plasma insulin concentration immediately post-exercise under hypoxia (14.8-16.5% oxygen) compared to normoxia.

  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).

Secondary Outcomes (3)

• 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.

Study Arms (2)

Moderate intensity exercise under normoxia

PLACEBO COMPARATOR

The participants will perform low-moderate intensity cycling exercise at 90% lactate threshold (LT) (determined during LT test) under normoxia (FiO2: 20.9%) for 60 minutes on a cycle ergometer. Immediately after exercise oral glucose tolerance test (OGTT) will be determined with 24-hour glucose concentration will be monitored continuously. Circulatory factors will be determined pre, immediately after exercise and 24 hours after exercise.

Other: Low-moderate intensity exercise under normoxia

Moderate intensity exercise under hypoxia

EXPERIMENTAL

The participants will perform low-moderate intensity cycling exercise at 90% lactate threshold (LT) (determined during LT test) under hypoxia (FiO2: 16.5-14.8%) for 60 minutes on a cycle ergometer. Immediately after exercise oral glucose tolerance test (OGTT) will be determined with 24-hour glucose concentration will be monitored continuously. Circulatory factors will be determined pre, immediately after exercise and 24 hours after exercise.

Other: Low-moderate intensity exercise under moderate hypoxia; Other: Low-moderate intensity exercise under high hypoxia

Interventions

Low-moderate intensity exercise under normoxia OTHER

The participant will perform the exercise interventions consisting of cycling at the 90% lactate threshold at normoxia (fraction oxygen: 20.9%) for 60 minutes on separate days (5-7 days). Immediately after exercise oral glucose tolerance test (OGTT) and 24-hour glucose concentration will be monitored continuously. Pre, post and post-24 h circulatory markers will be determined.

Moderate intensity exercise under normoxia

Low-moderate intensity exercise under moderate hypoxia OTHER

The participant will perform the exercise interventions consisting of cycling at the 90% lactate threshold at normoxia (fraction oxygen: 16.5%) for 60 minutes on separate days (5-7 days). Immediately after exercise oral glucose tolerance test (OGTT) and 24-hour glucose concentration will be monitored continuously. Pre, post and post-24 h circulatory markers will be determined.

Moderate intensity exercise under hypoxia

Low-moderate intensity exercise under high hypoxia OTHER

The participant will perform the exercise interventions consisting of cycling at the 90% lactate threshold at normoxia (fraction oxygen: 14.8%) for 60 minutes on separate days (5-7 days). Immediately after exercise oral glucose tolerance test (OGTT) and 24-hour glucose concentration will be monitored continuously. Pre, post and post-24 h circulatory markers will be determined.

Moderate intensity exercise under hypoxia

Eligibility Criteria

• Age: 20 Years - 40 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• 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

You may not qualify if:

• Impaired glucose tolerance (2 hour glucose: \>7.8 - 11.1 mmol/L)
• Type 2 diabetes mellitus
• Obstructive sleep apnea
• Chronic obstructive pulmonary disease

Sponsors & Collaborators

• Swinburne University of Technology: lead
• National Sports Institute of Malaysia: collaborator

Study Sites (1)

National Sports Institute of Malaysia

Kuala Lumpur, 57000, Malaysia

Location

MeSH Terms

Conditions

Overweight; Sedentary Behavior; Hypoxia; Motor Activity

Condition Hierarchy (Ancestors)

Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Behavior; Signs and Symptoms, Respiratory

Study Officials

• Donny Camera, PhD

  Swinburne University of Technology

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Participants will be required to complete 3 exercise interventions.

Study Record Dates

• First Submitted: September 29, 2022
• First Posted: October 13, 2022
• Study Start: June 3, 2021
• Primary Completion: March 17, 2022
• Study Completion: March 17, 2022
• Last Updated: October 13, 2022

Record last verified: 2022-09

Data Sharing

• IPD Sharing: Will not share

Locations

MY (1)