A Randomized Trial of Recommendations for Exercise to Prevent Weight Regain (POWeR)

The investigators will conduct a randomized trial to evaluate the effectiveness of 3 levels of recommended exercise in initially overweight and obese sedentary men and women on the prevention of weight regain. Participants will complete a 3 mo. weight loss intervention of decreased energy intake (EI) and increased energy expenditure (100 minutes of physical activity per week). Participants achieving clinically significant weight loss (> 5% of initial weight), will be randomly assigned to 12 mos. of exercise at levels of energy expenditure of exercise (EEEx) recommended by Health and Human Services (HHS), American College of Sports Medicine(ACSM), Institute of Medicine (IOM): 150, 225, or 300 minutes per week. Major outcome assessments will occur prior to weight loss (-3 mos.), at completion of weight loss (0 mos.), at the midpoint (6 mos.), and completion of weight maintenance (12 mos.).

Study Overview

• Status: Completed
• Conditions: Obesity; Overweight; Weight Loss
• Intervention / Treatment: Behavioral: 150 Min/Week; Behavioral: 225 Min/Week; Behavioral: 300 Min/Week

Detailed Description

The investigators propose a randomized trial in 287 overweight and obese, sedentary adults (at least 50% women). Participants achieving clinically significant weight loss (≥5%) following a 3 mo. reduced energy diet and a program of PA (100 min/wk) will be randomly assigned to either maintain exercise at 150 min/wk. or increase exercise to 225 min/wk or 300 min/wk. while consuming a weight gain prevention diet over a 12 mo. period. Exercise will be verified (combination of on-site and HR monitor) and EEEx will be measured at 5 mo. intervals beginning at mo. 5. In-person behaviorally based clinic meetings will be conducted weekly during the 3 mo. weight loss period (-3 to 0 mos.) and during the first 3 mos. of the weight regain prevention period. During the final 9 mos. of weight regain prevention, clinics will be held bi-monthly using group conference calls. We have not proposed to randomize participants to a true control group (i.e. no exercise or diet) following the 3 mo. weight loss program as published data indicates significant weight regain in individuals receiving no follow-up treatment after weight loss.

• Study Type: Interventional
• Enrollment (Actual): 287
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Kansas
    • Lawrence, Kansas, United States, 66045
      • University of Kansas - Robinson Hall

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 55 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age 21 to 55 years.
• BMI of 25 to 45.0.
• Clearance for participation from their Primary Care Physician (PCP)

Exclusion Criteria:

• Participation in a research project involving weight loss or exercise in the previous 6 mos., as these proximal experiences may impact the results of this study.
• Participation in a regular exercise program (i.e., > 500 kcal/wk. of planned activity as estimated by questionnaire)
• Not weight stable (+ or - 4.5 kg) for 3 mos. prior to intake.
• Unwilling to be randomized to 1 of 3 exercise groups subsequent to weight loss.
• Pregnant during the previous 6 mos., lactating, or planned pregnancy in the following 15 mos.
• Serious medical risk such as type 1 diabetes, cancer, recent cardiac event (i.e., heart attack, angioplasty, etc.). This is determined by the individual's physician via the clearance to participate in the investigation and the health history (Appendix) interpreted by the staff physician.
• Eating disorders as determined by the Eating Attitudes Test using a score of 20 or greater
• Current treatment for psychological problems, or taking psychotropic medications
• Medications known to significantly affect weight (gain or loss).
• Adherence to specialized diet regimens, i.e., multiple food allergies, vegetarian, macrobiotic, etc.
• Do not have access to grocery shopping and meal preparation (i.e. those in military, college with cafeteria plan, etc.).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: 150 Minutes per Week; Performs 150 minutes of physical activity per week.	Behavioral: 150 Min/Week; Performs 150 min/wk of planned moderate intensity aerobic exercise.
Active Comparator: 225 Minutes per Week; Performs 225 minutes of physical activity per week.	Behavioral: 225 Min/Week; Performs 225 min/wk of planned moderate intensity aerobic exercise.
Active Comparator: 300 Minutes per Week; Performs 300 minutes of physical activity per week.	Behavioral: 300 Min/Week; Performs 300 min/wk of planned moderate intensity aerobic exercise.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevention of Weight Regain	To compare the effectiveness of 3 exercise recommendations on the prevention of weight regain over 12 mos. subsequent to clinically significant weight loss (> 5%). We expect participants will regain weight in a dose-response manner, i.e. greatest, intermediate and least weight regain for the 150, 225, and 300 minute. groups, respectively.	12 Months
Gender Differences in Weight Regain	To evaluate gender differences in weight regain over 12 months in response to 3 exercise recommendations. Based on available preliminary data we expect men will regain less weight than women.	12 Months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Compensatory Changes to three exercise levels	Evaluating the impact of potential compensatory changes in daily physical activity and energy intake on weight regain in response to 3 exercise recommendations. Any observed compensatory responses would inform the development of subsequent targeted interventions.	12 Months

Collaborators and Investigators

• Sponsor: University of Kansas
• Collaborators: National Heart, Lung, and Blood Institute (NHLBI)
• Investigators: Principal Investigator: Joseph Donnelly, EdD, University of Kansas

Publications and helpful links

General Publications

• Szabo AN, Washburn RA, Sullivan DK, Honas JJ, Mayo MS, Goetz J, Lee J, Donnelly JE. The Midwest Exercise Trial for the Prevention of Weight Regain: MET POWeR. Contemp Clin Trials. 2013 Nov;36(2):470-8. doi: 10.1016/j.cct.2013.08.011. Epub 2013 Sep 4.

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2012
• Primary Completion (Actual): April 1, 2018
• Study Completion (Actual): December 31, 2018

Study Registration Dates

• First Submitted: August 10, 2012
• First Submitted That Met QC Criteria: August 10, 2012
• First Posted (Estimate): August 14, 2012

Study Record Updates

• Last Update Posted (Actual): April 18, 2019
• Last Update Submitted That Met QC Criteria: April 16, 2019
• Last Verified: April 1, 2019

More Information

Terms related to this study

• Keywords: Exercise; Obesity; Overweight; Weight Loss
• Additional Relevant MeSH Terms: Body Weight Changes; Weight Loss; Overweight; Body Weight
• Other Study ID Numbers: HSCL19775; R01HL111842 (U.S. NIH Grant/Contract)