Acute and Chronic Metabolic Flexibility in Individuals Living With Obesity: The i-FLEX Study

Not Applicable

Completed

• Conditions: Exercise; Obesity; Endocrine; Insulin Sensitivity; Obesity
• Interventions: Behavioral: Sprint Interval Training

• Registration Number: NCT03527446
• Lead Sponsor: University of New Brunswick

Brief Summary

Regular exercise is a cornerstone in the prevention and the management of cardio-metabolic risk factors. Some of the beneficial effect of exercise training occurs through metabolic flexibility' enhancement. Metabolic flexibility is the ability to respond or adapt to conditional changes in metabolic demand, and previous literature has shown that individuals living with obesity have an impaired metabolic flexibility compared to lean individuals. However, there is a lack of empirical evidence on the impact of sprint interval training on metabolic flexibility and whether this translates into clinically meaningful outcomes.

This study will evaluate the impact of 4-week sprint interval training in normal weight individuals as well as individuals living with obesity on acute and chronic metabolic flexibility, irisin secretion and insulin sensitivity.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2018-05-03
• Study First Submitted QC: 2018-05-15
• Study First Posted: 2018-05-17
• Study Start: 2018-07-03
• Primary Completion: 2020-02-28
• Study Completion: 2020-02-28
• Status Verified: 2020-03
• Last Update Submitted: 2020-03-24
• Last Update Posted: 2020-03-25

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 34

Inclusion Criteria

• Adults (Ages 19-60)
• Physically inactive for individuals living with obesity (not meeting Canadian Physical Activity Guidelines)
• Normal Weight (BMI ≥ 18.5 < 25.0 km/m2)
• Obesity (BMI ≥ 30.0 km/m2)

Exclusion Criteria

• Individuals with Type 2 Diabetes.
• Individuals with impaired glucose tolerance.
• Individuals living with obesity that partake in regular exercise training / meet the Canadian Physical Activity Guidelines.
• Individuals with a condition or injury that may impact the ability to perform exercise or may be worsened by exercise.
• Individuals currently being treated with corticosteroids or atypical antipsychotics, as these agents significantly influence carbohydrate metabolism.
• have experienced >10% weight loss or enrolled in weight loss program within six months of enrolment.
• require use of medication(s) known to affect insulin sensitivity or secretion within the last 30 days.
• Medication(s) known to cause weight gain.
• weight loss medication(s).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Normal Weight	Sprint Interval Training	BMI ≥ 18.5 \< 25.0 km/m2 Sprint Interval Training
Individuals living with Obesity	Sprint Interval Training	BMI ≥ 30.0 km/m2 Sprint Interval Training

Primary Outcome Measures

Name	Time	Method
Change in Metabolic Flexibility	Baseline and post-intervention (4 weeks)	Chronic and acute metabolic flexibility will be quantified from the respiratory quotient (RQ) at rest and from the respiratory exchange ratio (RER) during a 4-6 minutes steady rate exercise bout.
Change in Insulin Sensitivity	Baseline and post-intervention (4 weeks)	Insulin sensitivity will be measure with the Matsuda Index

Secondary Outcome Measures

Name	Time	Method
Change in Irisin	Baseline and post-intervention (4 weeks)	This hormone will be quantified in the plasma during one acute session of exercise.

Trial Locations

Locations (1)

University of New Brunswick - Kinesiology; 🇨🇦 Fredericton, New Brunswick, Canada