Exercise-Induced Metabolic Compensation; a Physiological Adaptive Response to Exercise Training

The primary aim of this proposal is to identify changes in the volume of highly metabolic organs (liver, kidneys, and brain) that occur as a physiological adaptation to exercise training and lower the resting energy expenditure. Secondary aims are to identify changes in the metabolic efficiency of muscle in low levels of physical activity and evaluate the effects on components of total daily energy expenditure including the sleeping metabolic rate (SMR) and diet induced thermogenesis (DIT).

Study Overview

• Status: Active, not recruiting
• Conditions: Exercise Training
• Intervention / Treatment: Behavioral: Exercise training

Detailed Description

Using a clinical trial type protocol, 16 overweight (body mass index: 25-30 kg/m2) men (n=8) and women (n=8) aged 21 to 45 years will exercise for 3 months in a moderate intensity regimen of 20 kcal/week/kg body weight that reflects current recommendations for weight management. The volume of various organs will be measured pre- and post-exercise intervention using magnetic resonance imaging (MRI). A cycling ergometer with a varied workload will be used to assess muscle metabolic efficiency. Changes in overnight SMR and 4 hours post breakfast DIT will be evaluated by whole human room indirect calorimetry ("metabolic chamber"). In addition, free-living Total Energy Expenditure (TEE) will be measured for ten days pre- and post-intervention by doubly labeled water.

• Study Type: Interventional
• Enrollment (Estimated): 16
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Israel
  • Other
    • Tel Aviv, Other, Israel, 6997801
      • Tel Aviv University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Overweight [body mass index (BMI) 25-30

Exclusion Criteria:

• Participation in another exercise or weight loss program in the last 6 months
• Non-stable weight (>±5%) over the past 6 months
• Current regular exercise > 1 hour per week
• Smoking within the past 6 months
• Being post-menopausal, breastfeeding, pregnancy, or having been pregnant within the past 6 months
• Previous bariatric surgery
• Cardiopulmonary disease (e.g., recent myocardial infarction or unstable angina)
• Musculoskeletal or neuromuscular impairments that preclude exercise training
• Having other health issues include cancer, diabetes, thyroid disease, hypertension, chronic renal failure, cognitive impairments
• Use of drugs that potentially impact body metabolism.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Intervention; Exercise in moderate intensity tailored individually to 20 kcal/kg/week (range 1500-2000 kcal/week) with a free choice to exercise at home/gym on a treadmill or outdoors.

Behavioral: Exercise training; The first phase of the study will comprise two weeks of control phase when participants will not engage in any exercise training but will be monitored for total daily energy expenditure and its components (REE, SMR, and DIT) and assessed volume of metabolic organs and skeletal muscle efficiency. Next, participants will start the active phase. In the first two weeks, participants will perform 150 - 200 min/week of a moderate intensity exercise so that they can adapt to the new regime and avoid injury. All exercise training will be monitored using heart rate sensor (HR) to track exercise adherence and HR range goals. Changes in daily non-exercise physical activity and sedentary behavior will be assessed for 10 days pre- and post-intervention by a tri-axial accelerometer. All study participants will be instructed to consume their habitual diet and to maintain the same caloric intake.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To examine long-term changes in the volume of highly metabolic organs (brain, liver, and kidneys) as an adaptive metabolic response to exercise training	The volume of various organs will be measured using magnetic resonance imaging (MRI).	Pre- and post 12 weeks of exercise intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To evaluate the changes in skeletal muscle metabolic efficiency during non- exercise physical activity as an adaptive response to long-term exercise training	A cycling ergometer with a varied workload will be used to assess muscle metabolic efficiency	Pre- and post 12 weeks of exercise intervention
To determine the effect of long-term exercise training on changes in sleeping metabolic rate as an adaptive response .	Changes in overnight sleeping metabolic rate will be evaluated by whole human room indirect calorimetry ("metabolic chamber")	Pre- and post 12 weeks of exercise intervention
To assess the effect of long-term exercise training on changes in diet induced thermogenesis as an adaptive response.	Changes in diet induced thermogenesis will be evaluated 4 hours post breakfast by whole human room indirect calorimetry ("metabolic chamber")	Pre- and post 12 weeks of exercise intervention

Collaborators and Investigators

• Sponsor: Tel Aviv University
• Collaborators: University of Colorado, Denver
• Investigators: Principal Investigator: Yftach Gepner, PhD, Tel Aviv University

Study record dates

Study Major Dates

• Study Start (Actual): March 27, 2021
• Primary Completion (Estimated): August 1, 2024
• Study Completion (Estimated): November 1, 2024

Study Registration Dates

• First Submitted: June 29, 2020
• First Submitted That Met QC Criteria: July 5, 2020
• First Posted (Actual): July 7, 2020

Study Record Updates

• Last Update Posted (Actual): February 22, 2024
• Last Update Submitted That Met QC Criteria: February 21, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Keywords: Energy expenditure; Exercise; Muscle; Metabolic adaptation
• Other Study ID Numbers: Metabolism

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No