Promotion of Exercise and Health in Obesity

Obesity Clinical Trial

— PESO  

Official title:

Moderators and Mediators of Physical Activity, Body Weight, and Body Composition Change During Obesity Treatment in Women

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT00513084
• Other study ID #: FCT-POCI/DES/57705/2004
• Status: Active, not recruiting
• Phase: N/A
• First received: August 7, 2007
• Last updated: August 7, 2007
• Start date: July 2004
• Est. completion date: July 2009

Study information

• Verified date: July 2007
• Source: Technical University of Lisbon
• Contact: n/a
• Is FDA regulated: No
• Health authority: Portugal: Health Ethic Committee
• Study type: Interventional

Clinical Trial Summary

The primary objectives of this randomized clinical trial are a) to implement and test the impact of a 1-year lifestyle obesity treatment program based on Self-Determination Theory on 3-year change in physical activity and motivation for exercise/physical activity, body weight and fat, and selected eating variables, b) to identify behavioral and psychosocial theory-based moderators or mediators of primary outcomes, especially physical activity and body weight.

Description:

Obesity and sedentary lifestyles are worldwide threats to public health but feasible and effective strategies to tackle these problems are scarce. The identification of variables that explain why only a sub-group of overweight persons succeeds at increasing physical activity and achieving long-term weight control is a key research topic in exercise and sports sciences. Subjects are 260 healthy women (BMI, 25 to 40 kg/m2), aged between 25 and 50 years, premenopausal, of whom half receive the treatment intervention, the remaining being randomly assigned to a control group at baseline. This RCT consists of a 1-year intervention plus a 2-year no contact follow-up period. The intervention group attended 30 weekly group sessions, designed to follow SDT basic tenets, covering PA, eating/nutrition, body image, and other cognitive and behavioral contents. Central to the intervention model are autonomy, intrinsic motivation, and self-regulation of behavior change. Autonomy-supportive treatment climate and internal causality orientations are predicted to enhance autonomous regulation, perceived competence, and intrinsic motivation for the targeted behaviors, resulting in lasting behavioral and body weight changes. The intervention was designed to follow SDT, with an emphasis on promoting intrinsic, self-regulated motivation for exercise and weight control. The control group received a general health education curriculum based on several 3- to 6-week long educational topics (e.g. food safety, stress management, self-care, body image, and others). Results are expected to contribute to a better understanding of how individual characteristics, particularly those related to physical activity and exercise influence success, better screening/readiness testing procedures, improved matching of interventions to participants, and lower rates of attrition and unsuccessful weight loss attempts.

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 259
• Est. completion date: July 2009
• Accepts healthy volunteers: No
• Gender: Female
• Age group: 25 Years to 50 Years

Eligibility

Inclusion Criteria:

• female (25-50 years old)

• pre-menopausal

• BMI between 25 and 40 kg/m2

• willing to attend weekly meetings (during 1 year)

• willing to not participate in other formal or informal weight loss program during the first year of the study (intervention group only).

Exclusion Criteria:

• major/chronic illness

• taking (or having taken in the previous year) medication known to interfere with body weight regulation, including anti-depressive medication

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Obesity

Intervention

Behavioral:
• SDT and Motivational Interviewing in Obesity Treatment
Thirty group sessions, designed to follow SDT, covering PA, eating/nutrition, body image, and other cognitive-behavioral contents. Central to the intervention are improving autonomy, intrinsic motivation, and self-regulation of behavior change. Accepting ambivalence for change, rolling with resistance, and developing discrepancy were used throughout the program, with an emphasis on promoting intrinsic, self-regulated motivation for exercise and weight control.

Locations

Country	Name	City	State
Portugal	Faculty of Human Movement, Technical University of Lisbon	Lisbon	Estrada da Costa

Sponsors (1)

Lead Sponsor	Collaborator
Technical University of Lisbon

Country where clinical trial is conducted

Portugal, 

References & Publications (2)

Minderico CS, Silva AM, Fields DA, Branco TL, Martins SS, Teixeira PJ, Sardinha LB. Changes in thoracic gas volume with air-displacement plethysmography after a weight loss program in overweight and obese women. Eur J Clin Nutr. 2008 Mar;62(3):444-50. Epu — View Citation

Teixeira PJ, Going SB, Houtkooper LB, Cussler EC, Metcalfe LL, Blew RM, Sardinha LB, Lohman TG. Exercise motivation, eating, and body image variables as predictors of weight control. Med Sci Sports Exerc. 2006 Jan;38(1):179-88. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Primary outcomes are physical activity/exercise and body weight/ composition. Physical activity is assessed by accelerometry and standardized interview/questionnaire methods. Body composition is assessed by DXA		baseline, 4, 12, 16, 24 and 36 months
Secondary	Dietary Intake, psychosocial SDT-based mediators		baseline, 4, 12,16, 24 and 36 months