Laboratory Model for Relapse to Sedentary Behavior
Condition: Exercise
MeSH terms: Recurrence
Study type: Interventional

Summary: 
      Physical inactivity is a key risk factor for noncommunicable illnesses such as cancer and
      cardiovascular disease-the two leading causes of death in West Virginia. The World Health
      Organization recommends muscle-strengthening activities 2 or more days per week and a minimum
      of either 150 minutes of moderate-intensity activity or 75 minutes of vigorous-intensity
      activity per week. Yet, only one in five adults in the United States meets these
      recommendations. Even more alarming is that 33.2% of West Virginians report that they did not
      engage in any physical activity in the past month. Incentive-based interventions increase
      physical activity in the short term, but incentives for healthy behavior are generally
      discontinued after some period of time, and relapse of unhealthy behavior is common. Thus,
      there is a critical need to develop interventions that result in both immediate and lasting
      engagement in activity. The overall objective and specific aim of the proposed project is to
      evaluate a brief laboratory model of relapse into sedentary behavior following
      incentive-based interventions that is based on Behavioral Momentum Theory. The central
      hypothesis is that incentives will increase activity, but relapse will occur in the brief
      model, like what occurs in extended clinical treatment. Development of a laboratory model of
      relapse into sedentary behavior (the expected outcome of the proposed project) will inform
      future translational research, eventually leading to clinical applications of large-scale
      physical-activity interventions that result in significant and immediate behavior change and
      that minimize relapse.
    

Detailed description: 
      Physical inactivity is a key risk factor for noncommunicable illnesses such as cancer and
      cardiovascular disease (CVD)-the two leading causes of death in West Virginia. Physical
      inactivity is fundamentally a behavior problem, and there is a growing body of research
      supporting the use of incentive-based interventions to increase physical activity. In such
      interventions, participants earn incentives such as money, tokens or points, entries into
      prize drawings, or fitness-related commodities (e.g., gym memberships) by meeting defined
      goals (e.g., daily steps, energy expenditure, fitness classes).

      A crucial feature of any successful intervention is sustained behavior-change following the
      removal or decrease in supports. However, most evaluations of incentive-based interventions
      are completed on a short-term scale (4 to 12 weeks) and often fail to provide data on
      follow-up. The studies that follow participants after the discontinuation of incentives often
      show relapse to sedentary behavior following intervention. Similar relapse is common
      following incentive-based interventions for other health-related behavior. Laboratory models
      of relapse prevention have informed treatment for these other forms of health-related
      behavior, but they have yet to be extended to interventions addressing sedentary behavior.

      The investigators' long-term goal is to develop practical interventions that sustain
      increases in physical activity and thereby decrease a significant risk factor for disease
      (e.g., cancer, diabetes). The overall objective of the proposed project is to evaluate a
      brief laboratory model of relapse that is based on basic behavioral research grounded in
      Behavioral Momentum Theory. The central hypothesis is that incentives in the brief model will
      produce the expected increases in physical activity relative to no-incentive controls, but
      that these gains will be rapidly lost when the incentives are discontinued. This hypothesis
      is based other laboratory-based models of relapse (e.g., illicit drug use and challenging
      behavior), which mirrored outcomes of, and led to advances in clinical, treatment. The
      rationale for this project is that a laboratory model of relapse of sedentary behavior will
      inform future translational research and lead to large-scale clinical trials of incentives to
      improve physical activity that result in large, immediate behavioral change and that minimize
      subsequent relapse.

      The central hypothesis is that incentives in the brief model will produce the expected
      increases in physical activity relative to no-incentive controls, but that these gains will
      be rapidly lost when the incentives are discontinued. These outcomes would suggest that the
      brief model produces outcomes similar to those obtained in more extended clinical treatment.

      Approach The anticipated number of participants is 30 individuals (age 18-74). Participants
      will attend a single 90-min laboratory appointment. The laboratory space will be equipped
      with a treadmill, comfortable seating, and leisure activities. A licensed nurse will screen
      participants to ensure they are healthy enough to engage in physical activity and will remain
      present for the duration of participation to provide medical assistance in the unlikely event
      that it is needed. Block randomization will be used to assign participants to one of three
      groups (one experimental and two control groups). All groups will experience three phases of
      the study. Opportunities for sedentary leisure and physical activities will be continuously
      available throughout all phases. The first phase will mimic pre-intervention conditions;
      there will be a variety of activities available. No incentives for engaging in physical
      activity will be provided, although such activities will be available. For the Relapse
      (experimental) Group, the second phase will mimic an incentive-based intervention in which
      participants can earn monetary incentives for engaging in physical activity. Then, during the
      third phase, the incentives will be discontinued the Fatigue Control group will experience
      the same conditions for Phase 1 and 2, but they will continue to earn incentives during Phase
      3. The No-Incentive Control group will not earn incentives during any phase to control for
      the possibility that participants will engage in some physical activity in the absence of
      incentives.

      Participants will wear a heart rate monitor throughout the study to provide real-time data on
      activity level and trained research assistants will use software to score time-stamped
      duration of engagement in available activities (e.g., walking, sitting). A one-way ANOVA will
      be used to compare mean durations of physical activity across groups. A power analysis[23]
      shows that including 30 participants (10 in each group) will provide sufficient power to
      detect an effect size of 0.8 at an alpha of 0.05. Additionally, the investigators will use
      the heart rate data for preliminary analyses of mediation and moderation effects.
    

Intervention name(s): Performance-based incentives
Intervention type(s): Behavioral
Intervention description(s): Participants will earn $1 per minute of engagement in physical activity.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Block randomization will be used to assign participants to one of three groups (one experimental and two control groups). All groups will experience three phases of the study. Opportunities for sedentary leisure and physical activities will be continuously available throughout all phases.
Masking: Single (Participant)
Primary purpose: Other
Keywords: Relapse; Physical Activity; Sedentary Behavior; Behavioral Momentum Theory; Incentives