Physical Activity in the Treatment of Obesity
Condition: Obesity
MeSH terms: Obesity
Study type: Interventional

Summary: 
      Although exercise is widely regarded as a key component in obesity treatment, few individuals
      seem able to adhere to exercise programs over time. In response, efforts have focused on
      developing new approaches to physical activity that may appeal to sedentary overweight
      persons. For instance, is has been shown that accumulating multiple short bouts of vigorous
      exercise may enhance both exercise adherence and weight loss in overweight persons.
      Accumulating moderate-intensity activity throughout the day may offer comparable health and
      weight benefits as a traditional exercise program. Public health recommendations now include
      the option of accumulating 30 minutes of moderate-intensity lifestyle activity for health and
      well-being. While these two options offer a viable alternative to those who dislike or cannot
      sustain continuous vigorous exercise programs, it is unclear whether the flexibility of
      accumulating physical activity or the vigorous intensity of the exercise is responsible for
      improved weight loss and long-term adherence.

      The goal of this research is to extend our preliminary findings suggesting that moderate
      intensity lifestyle activity is an important and viable alternative to traditional structured
      vigorous exercise for obese dieting individuals. The primary specific aim of this project is
      to compare the effects of three modes of exercise on long-term weight regain. Participants
      will be 165 overweight men and women who are sedentary, but otherwise healthy. All
      participants will receive the same 16-week behavioral weight loss program and will be
      randomized to one of three exercise study conditions: 1) diet-plus-continuous bouts of
      vigorous aerobic exercise; 2) diet-plus-short bouts of vigorous aerobic exercise accumulated
      throughout the day; or 3) diet-plus-moderate intensity lifestyle activity accumulated
      throughout the day. By varying both the intensity and duration of exercise bouts, we can
      determine which type of exercise is associated with optimal outcomes one year later.
      Additional questions of interest include:

        1. Does mode of exercise influence exercise adherence?

        2. Does mode of exercise improve cardiovascular risk profiles similarly in all three
           conditions?

        3. Does mode of exercise influence changes in body composition?

        4. Does mode of exercise influence exercise enjoyment and exercise self-efficacy?
    


Intervention name(s): Diet plus continuous bouts; Diet plus short bouts; Diet plus moderate lifestyle activity
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): Patients consumed a 1200 kcal/d diet and were instructed to perform 4 30-60 minute aerobic workouts per week; Patients consumed a 1200 kcal/d diet and were instructed to perform short 10 minutes bouts of aerobic exercise 4 times per week; Patients consumed a 1200 kcal/d diet and were instructed to accumulate moderate intensity physical activity on most days of the week.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: overweight, physical activity, body composition, metabolic syndrome