Effect of Exercise and Weight Loss on Cardiovascular Health
Condition: Cardiovascular Disease; Obesity
MeSH terms: Cardiovascular Diseases; Weight Loss
Study type: Interventional

Summary: 
      The primary aim of this study is to examine the effect of the consensus public health
      recommended level of physical activity [moderate physical activity (MOD-PA) = 150 min/wk]
      versus a higher dose of physical activity [high physical activity (HIGH-PA) = 250 min/wk] in
      the context of a comprehensive behavioral weight loss program that a includes a reduction in
      energy intake measures of cardiovascular function using cardiac MRI and biomarkers of
      vascular disease risk. Each of these exercise doses will be compared independently to a Diet
      Only group intervention on the proposed primary and secondary outcomes, with MOD-PA also
      compared to HIGH-PA. This study involves the recruitment of 390 overweight and obese adults
      who will be randomly assigned to one of the above conditions (Diet Only, MOD-PA, HIGH-PA) for
      a period of 12 months. The primary outcome is LVM measured by cardiac MRI. Secondary outcomes
      include additional cardiac MRI measures (aortic pulse wave velocity, end diastolic volume,
      aortic distensibility), inflammatory markers (CRP and TNFα) and selected adipocytokines
      (adiponectin) as biomarkers of risk related to vascular outcomes, body weight, body
      composition, and cardiorespiratory fitness, and traditional CVD risk factors (lipids,
      glucose, insulin, blood pressure). Additional secondary analyses will allow for examination
      of the effects of physical activity independent of weight change on the primary and secondary
      outcomes.
    

Detailed description: 
      Current estimates indicate that in excess of 65 percent of adults in the United States are
      overweight (BMI >25.0 kg/m2) with at least 30 percent of adults classified as obese (BMI >30
      kg/m2). Overweight and obesity have been linked to numerous chronic conditions including
      cardiovascular disease. The application of cardiac MRI (CMRI) allows for direct measurement
      of the cardiac structure, and left ventricular mass (LVM) assessed by CMRI has been shown to
      be predictive of cardiovascular disease. Recent studies have shown that LVM is decreased with
      weight loss; however, there is a lack of information on the added benefit of physical
      activity to weight loss on these direct measures of cardiovascular structure and function.
      Thus, consistent with PA-09-243, this study will examine the effect of two recommended doses
      of physical activity combined with a dietary intervention on changes in the proposed outcomes
      of cardiovascular disease risk in overweight adults.

      The primary aim of this study is to examine the effect of the consensus public health
      recommended level of physical activity [moderate physical activity (MOD-PA) = 150 min/wk]
      versus a higher dose of physical activity [high physical activity (HIGH-PA) = 250 min/wk] in
      the context of a comprehensive behavioral weight loss program that a includes a reduction in
      energy intake measures of cardiovascular function using cardiac MRI and biomarkers of
      vascular disease risk. Each of these exercise doses will be compared independently to a Diet
      Only group intervention on the proposed primary and secondary outcomes, with MOD-PA also
      compared to HIGH-PA. This study involves the recruitment of 390 overweight and obese adults
      who will be randomly assigned to one of the above conditions (Diet Only, MOD-PA, HIGH-PA) for
      a period of 12 months. The primary outcome is LVM measured by cardiac MRI. Secondary outcomes
      include additional cardiac MRI measures (aortic pulse wave velocity, end diastolic volume,
      aortic distensibility), inflammatory markers (CRP and TNFα) and selected adipocytokines
      (adiponectin) as biomarkers of risk related to vascular outcomes, body weight, body
      composition, and cardiorespiratory fitness, and traditional CVD risk factors (lipids,
      glucose, insulin, blood pressure). Additional secondary analyses will allow for examination
      of the effects of physical activity independent of weight change on the primary and secondary
      outcomes.
    

Intervention name(s): Behavioral weight loss intervention; Diet Plus Moderate Exercise; Diet Plus High Exercise
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): Weight loss intervention that focuses on reducing energy intake.; Weight loss intervention that involve an energy restricted diet (identical to the Diet Alone arm) plus the inclusion of 150 minutes per week of moderate-intensity exercise.; Weight loss intervention that involve an energy restricted diet (identical to the Diet Alone arm) plus the inclusion of 250-300 minutes per week of moderate-intensity exercise.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: cardiovascular disease; obesity; exercise