NCT00622310

Brief Summary

This project is aimed at determining whether an exercise-based weight loss intervention causes a compensation in some component of energy expenditure such that the increase in measured energy expenditure is less than the added exercise. The study will compare two separate exercise interventions to determine if this is influenced by exercise intensity.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
30

participants targeted

Target at below P25 for not_applicable obesity

Timeline
Completed

Started Sep 2007

Shorter than P25 for not_applicable obesity

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

September 1, 2007

Completed
6 months until next milestone

First Submitted

Initial submission to the registry

February 21, 2008

Completed
4 days until next milestone

First Posted

Study publicly available on registry

February 25, 2008

Completed
3 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 1, 2008

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

June 1, 2008

Completed
Last Updated

July 12, 2021

Status Verified

July 1, 2021

Enrollment Period

9 months

First QC Date

February 21, 2008

Last Update Submit

July 6, 2021

Conditions

Outcome Measures

Primary Outcomes (1)

  • Total daily energy expenditure, assessed using doubly labeled water

    Prior to exercise intervention, and 6 months

Secondary Outcomes (2)

  • Total daily activity thermogenesis

    Prior to exercise intervention, and 6 months

  • Body weight and composition

    Prior to exercise intervention, and 6 months

Study Arms (2)

1 Exercise

EXPERIMENTAL

Subjects in the EX group will perform supervised exercise 5 d/wk. Exercise will consist primarily of walking on an inclined motor-driven treadmill, but alternate activities will be permitted for 20% of the total exercise sessions (1 of 5 days). Exercise sessions will be preceded by a 5 min warm-up performed at a HR corresponding to 40% of VO2max. The initial exercise duration and intensity at baseline will be 20 minutes at an intensity that elicits a heart rate (HR) corresponding to 60% of VO2max. The target EE will be achieved by a gradual progression of exercise duration and intensity over the first 8 weeks of the exercise program. The target exercise intensity will be the workload corresponding to 75% of VO2max.

Behavioral: Walking exercise

2 Walk

EXPERIMENTAL

Subjects in the WALK group will also perform exercise 5 d/wk. Exercise will consist exclusively of walking on level grades, and will be prescribed in two equal duration bouts each day. Subjects in the WALK group will be individually prescribed a walking program based on the EE during moderate intensity walking. The target exercise intensity will be walking speeds corresponding 45% of VO2max.

Behavioral: Walking exercise

Interventions

Subjects will be randomly assigned to either a structured, vigorous-intensity endurance exercise training program or an intermittent, low-intensity exercise program. Individualized exercise prescriptions will be designed to target an increase of 2500 kcal/wk, and the theoretical weight loss will be approximately 15 pounds (\~6.8 kg) during the 6 month intervention.

1 Exercise2 Walk

Eligibility Criteria

Age18 Years - 55 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • Body mass index (BMI) 30-35.0 kg/m2
  • Age 18-45 years
  • Weight stable (\<2 kg weight fluctuation during previous 6 months)
  • No regular exercise (\> 1 bout of exercise/wk or participation in any sporting activities \> 1 hr/wk)
  • No self-report of acute or chronic disease (diabetes, heart diseases, and joint problems in particular)
  • No current use of prescribed medications
  • No plans to relocate within the next year
  • No plans for extended travel (\> 1 week) within the next 6 months
  • No tobacco use
  • For Females:
  • No evidence of amenorrhea (Regular menstrual cycles of 21-35 days)
  • Pre-menopausal status (self-report, to be confirmed during screening)
  • Pregnancy or lactating within the past year
  • No pregnancy or planned pregnancies; sexually active women of childbearing potential may be enrolled if they have had a tubal ligation or use one of the following means of contraception: condom, diaphragm, oral or implanted contraceptives, or intrauterine device. Women in exclusive relationships with male partners who have had a successful vasectomy will not be required to use any additional means of birth control.

You may not qualify if:

  • Claustrphobia;
  • Any contraindication(s) to \> MRI, e.g. aneurysm, cochlear implant, cardiac pacemaker, or implantable cardiac defibrillator, artificial heart valve, metallic stents, any implantable devices or shunt, weight less than 300 lbs;
  • Left Handed.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Colorado, School of Medicine

Aurora, Colorado, 80045, United States

Location

MeSH Terms

Conditions

Obesity

Condition Hierarchy (Ancestors)

OverweightOvernutritionNutrition DisordersNutritional and Metabolic DiseasesBody WeightSigns and SymptomsPathological Conditions, Signs and Symptoms

Study Officials

  • Edward Melanson, PhD

    University of Colorado Division of Endocrinology, Metabolism, and Diabetes/Division of Geriatrics

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
OTHER
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

February 21, 2008

First Posted

February 25, 2008

Study Start

September 1, 2007

Primary Completion

June 1, 2008

Study Completion

June 1, 2008

Last Updated

July 12, 2021

Record last verified: 2021-07

Locations