Feasibility of a Campaign Intervention Compared to a Standard Behavioral Weight Loss Intervention in Overweight and Obese Adults

Feasibility of a Campaign Intervention Compared to a Standard Behavioral Weight Loss Intervention in Overweight and Obese Adults

Feasibility of a Campaign Intervention Compared to a Standard Behavioral Weight Loss Intervention in Overweight and Obese Adults

The purpose of this study is to examine the feasibility of a campaign intervention for weight management compared to a standard behavioral weight loss intervention in overweight and obese adults.

The feasibility of solely using a campaign intervention (CI) to promote healthy eating and physical activity behaviors for weight loss and weight maintenance has not been examined in a systematic manner. Thus, the primary aim of this study will be to examine whether a stand-alone CI results in similar weight loss compared to a standard behavioral weight loss intervention (SBWL). It is hypothesized that the CI will achieve a similar weight loss when compared to the SBWL. Additional aims include the examination of the CI on changes in moderate to vigorous intensity physical activity, dietary intake, self-monitoring of dietary intake and physical activity, weight loss self-efficacy, and motivation compared to a SBWL. This study will recruit forty-eight sedentary, overweight and obese adult men and women, to participate in a behavioral weight loss intervention at the University of Pittsburgh Physical Activity and Weight Management Research Center (PAWMRC). To be considered eligible for this study, participants must be 18-55 years of age, with a Body Mass Index (BMI) ranging from ≥25.0 kg/m² to 45.0 kg/m². Assessments will be conducted at week 0 and 12 of the intervention. Each assessment will take approximately 30 minutes to complete and include height, body weight, and assessment of physical activity, dietary intake, weight loss self-efficacy, and motivation. Upon successful completion of baseline assessments, eligible subjects will be randomly assigned to one of two groups using a stratified randomized block design: 1) standard behavioral weight loss intervention (SBWL) or 2) campaign intervention (CI). The CI will target specific diet and physical activity behaviors to improve weight loss efforts within a thematic framework based on the professional auto racing point system concept. CI session content and targeted behavior goals will tie into this overall theme and throughout the campaign participants will have the opportunity to earn incentives to reinforce positive behavior changes. This study is a necessary first step to examine the feasibility of a stand-alone campaign as an alternative strategy for weight management when compared to a standard behavioral weight loss intervention. Furthermore, this study will provide variance estimates on the effectiveness of a campaign intervention compared to a standard behavioral weight loss program that can be used to determine appropriate sample sizes for a future full-scale clinical study of this alternative strategy.

Included changing eating behaviors, increasing physical activity, and attending regular group weight loss meetings.

Included changing eating behaviors and increasing physical activity, however participants will not attend regular meetings. Instead they will attend two weekly meetings at weeks 0 and 12. During the weeks they are not scheduled to attend in-person weekly meetings (weeks 1-11), they will receive education materials via e-mail. They will also have the opportunity to earn points towards prizes by reporting diet and physical activity behaviors, and body weight via e-mail.

Included changing eating behaviors, increasing physical activity, and attending regular group weight loss meetings.

Included changing eating behaviors and increasing physical activity, however participants will not attend regular meetings. Instead they will attend two weekly meetings at weeks 0 and 12. During the weeks they are not scheduled to attend in-person weekly meetings (weeks 1-11), they will receive education materials via e-mail. They will also have the opportunity to earn points towards prizes by reporting diet and physical activity behaviors, and body weight via e-mail.

Body weight will be measured on a digital scale to assess change in body weight over the 12-week intervention period.

A questionnaire will be used to assess self-reported food intake. This will be used to estimate calories, dietary fat, protein, and carbohydrates consumed.

A questionnaire will be used to assess self-reported food intake. This will be used to estimate calories, dietary fat, protein, and carbohydrates consumed.

A questionnaire will be used to assess self-reported food intake. This will be used to estimate calories, dietary fat, protein, and carbohydrates consumed.

A questionnaire will be used to assess self-reported food intake. This will be used to estimate calories, dietary fat, protein, and carbohydrates consumed.

The frequency that participants engaged in the self-monitoring of dietary intake and physical activity was assessed at week 12. The diaries were completed weekly throughout the study.

Self-efficacy for weight loss was assessed at week 0 and 12 using a 20-item Weight Efficacy Lifestyle Questionnaire (WEL). The total score ranges from 0-180. Higher values represent greater beliefs toward the completion of weight management behaviors.

At week 12, participants completed the 13-item TSRQ to assess motivation to continue to participate in the program if given the opportunity. The TSRQ represents participants' reasons for continuing participation in a weight loss program via participants' endorsement of statements of autonomous and controlled motivation. Responses were given using a 7-point Likert scale (1 = not at all true to 7 = very true). The responses on the autonomous items (5) and controlled items (8) were averaged.

Inclusion Criteria: 18-55 years of age Body mass index (BMI) ranging from ≥25.0 kg/m² to 45.0 kg/m² Ability to provide informed consent Exclusion Criteria: Regular exercise participation of at least 20 minutes per day on at least 3 days per week during the previous six months. Participation in a previous physical activity or weight management research project in the previous 6 months. Weight loss of ≥5% of current body weight in the previous 6 months. For women, those currently pregnant, pregnant during the previous 6 months, or plan on becoming pregnant in the next 6 months. History of myocardial infarction, coronary bypass surgery, angioplasty, or other heart-related surgeries. History of orthopedic or physical complications that would prevent participation in exercise. Currently taking any prescription medication that may affect metabolism and/or body weight (e.g., synthroid). Currently being treated for any condition that could affect body weight, such as coronary heart disease, diabetes mellitus, uncontrolled hypertension, cancer, depression, and anxiety. Currently being treated for any psychological issues or problems, taking any psychotropic medications, or receiving treatment with psychotropic medications within the previous 6 months. Resting systolic blood pressure ≥150mmHg or diastolic blood pressure ≥100mmHg. Subjects with controlled hypertension will be allowed to participate if they obtain a medical doctor's written consent to ensure that it is safe to participate in a weight loss intervention. Currently do not have access to a computer and the Internet.

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