Barriers to Physical Activity in People With Type 2 Diabetes
Condition: Type 2 Diabetes
MeSH terms: Diabetes Mellitus; Diabetes Mellitus, Type 2
Study type: Interventional

Summary: 
      The investigators plan to learn more about how different levels of exercise feel to people
      with Type 2 Diabetes and how it feels to people without Type 2 Diabetes. This study team will
      also look at what causes exercise to feel harder or easier to people with and without Type 2
      Diabetes. The investigators will also compare the potential benefits of supervised exercise
      training to that of diabetes education/blood sugar monitoring.
    

Detailed description: 
      Exercise is a potent therapy to reduce cardiovascular mortality in Type 2 Diabetes (T2D).
      Although exercise is a cornerstone of treatment for T2D, people with T2D are more sedentary
      than similarly obese people without diabetes, for reasons that are unclear. Interventions
      which combined behavioral support and physical activity prescriptions successfully increased
      physical activity levels for people with T2D and at-risk for T2D. However, the program
      components which mediated increased physical activity were combined and thus the individual
      benefits of each component remain unknown. Given the success of these combined programs, it
      appears behavioral support and other psychological factors may play an important role. The
      study investigators are interested in the predictors of physical activity adherence in T2D as
      key targets for future interventions.

      One likely factor which may influence physical activity adherence is perceived exercise
      effort. The study investigators reported, based on a small study, that perceived exercise
      effort is worse in people with T2D than in healthy obese controls, as measured by the Borg
      Rating of Perceived Exertion (RPE), even during low intensity exercise. Thus, one strategy to
      increase physical activity in T2D is to first identify the mediators of RPE in the proposed
      study and then to address them in future studies. The preliminary data suggest that likely
      mediators of RPE are both objective and subjective in nature. A key objective mediator of RPE
      is serum lactate level during exercise, which is a physiological marker of effort, and is
      disproportionately elevated in people with T2D vs. healthy controls. A key subjective
      mediator of RPE is self-efficacy, which influences the perception of exercise effort, and is
      disproportionately worse in people with T2D vs. healthy controls. To develop optimal physical
      activity interventions for people with T2D, the study investigators must understand whether
      RPE differences vary across the spectrum of exercise intensities (Aim 1), and the
      investigators must also determine the mediators of RPE across exercise intensities (Aim 2).
      Mediators of RPE in low-to-moderate intensity exercise are particularly important, because
      walking is a preferred physical activity for people with T2D.
    

Intervention name(s): Placebo Attention Control; Supervised Exercise Training
Intervention type(s): Behavioral; Other
Intervention description(s): The placebo attention control group will receive weekly phone calls to monitor their blood glucose levels.; The 20-week aerobic exercise training intervention provides supervised exercise training sessions 3 times weekly following the HERITAGE study training model that was feasible in prior studies with older, sedentary overweight adults (55%maximal oxygen uptake (VO2max) for 30 minutes per session at study entry with progressive titration to 70-80% VO2max for 50 minutes).
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Type 2 Diabetes; Exercise; Rate of Perceived Exertion