Adherence to Self-Paced vs Prescribed Intensity PA: Exploring Mechanisms via EMA

描述（由申请人提供）：大约60%的美国人口超重或肥胖，肥胖与许多健康问题有关。已经向超重和肥胖的成年人推荐身体活动以增强体重减轻和/或体重维持，并降低慢性疾病的风险，包括心脏病和乳腺癌和结肠癌。尽管运动有好处，但只有20%的超重或肥胖成年人符合最低国家建议（30分钟/天，5天/周），并且在运动计划的前几个月退出的比例高达50%。鉴于这些数据，有必要提高对运动计划的坚持性，特别是对于超重和肥胖的成年人。与流行的理论模型一致，运动促进干预通常侧重于认知（例如，自我效能）和社会（例如，社会支持）因素，但通常不针对情感过程。另一种观点是，享乐理论认为，一种行为的持续是由一个人对这种行为的感觉所引导的。与快乐理论相一致，我们最近表明，在运动促进计划的基线上享受身体活动可以预测干预的成功。此外，最近的研究检查了运动期间的情感反应，结果表明，单独的中等强度运动（例如，快步走）会导致超重和久坐的成年人产生严重的负面情绪反应，可能会使坚持锻炼变得更加困难。或者，当超重的成年人选择自己的步行速度时，它会导致比规定特定强度时更积极的情感反应。因此，在这项研究中，我们将检查与规定的中等强度步行相比，自行步速步行对超重或肥胖个体坚持其他相同的六个月步行计划的影响。我们假设，建议超重成年人进行自定步调的强度运动将导致更好地遵守该计划（即，更多分钟的运动），而不是像公共卫生指南中建议的那样，规定中等强度的运动。如果我们的假设得到证实，研究结果将为久坐、超重和肥胖的成年人提供未来的锻炼建议。此外，与享乐理论一致，我们将探索对运动的急性情感反应，作为使用生态瞬时评估（EMA;即，电子日记）。如果在参与者的自然环境中真实的时间评估的对运动的情感反应被证明可以预测对步行计划的坚持，这将表明需要更多地关注健康行为模型中的情感变量，并将其作为健康促进干预的目标。公共卫生相关性：对于超重和肥胖的成年人来说，自定步调的锻炼可能比规定的中等强度的锻炼更令人愉快，更容易维持（例如，快步走），从而导致更好的依从性，从而导致更好的健康结果。在这项研究中，我们将比较久坐、超重和肥胖的成年人对自定步调运动和规定的中等强度运动的坚持率。我们还将要求参与者在每次锻炼过程中使用手持电子日记来评估他们的感受，以确定这些感受是否与坚持步行计划有关。

DESCRIPTION (provided by applicant): Approximately 60 percent of the U.S. population is overweight or obese, and obesity has been linked to numerous health problems. Physical activity has been recommended for overweight and obese adults to enhance weight- loss and/or weight-maintenance, and to reduce risk of chronic disease, including heart disease and cancers of the breast and colon. Despite the benefits of exercise, only 20 percent of overweight or obese adults meet the minimum national recommendations (30 min/day, 5 days/week), and drop out in the first few months of exercise programs is as high as 50 percent. Given these data, there is a need to improve adherence to exercise programs, especially for overweight and obese adults. Consistent with prevailing theoretical models, exercise promotion interventions typically focus on cognitive (e.g., self-efficacy) and social (e.g., social support) factors, but do not typically target affective processes. Alternatively, Hedonic Theory posits that continuation of a behavior is guided by how one feels as a consequence of performing the behavior. Consistent with Hedonic Theory, we have recently shown that enjoyment of physical activity at baseline of an exercise promotion program predicted intervention success. Moreover, recent research examining affective responses during exercise has shown that individual bouts of moderate intensity exercise (e.g., a brisk walk) can lead to acute negative affective responses among overweight and sedentary adults, potentially making exercise adherence more difficult. Alternatively, when overweight adults choose their own walking pace, it results in a more positive affective response than when a specific intensity is prescribed. Therefore, in this study we will examine the effects of self-paced walking compared to prescribed moderate intensity walking on adherence to otherwise identical, six-month walking programs among overweight or obese individuals. We hypothesize that recommending self-paced intensity exercise for overweight adults will result in better adherence to the program (i.e., more minutes of exercise) than prescribing exercise at moderate intensity, as recommended in public health guidelines. If our hypothesis is confirmed, the results will inform future exercise recommendations among sedentary, overweight and obese adults. Additionally, consistent with Hedonic Theory, we will explore acute affective responses to exercise as a predictor of adherence to the exercise program using ecological momentary assessment (EMA; i.e., electronic diaries). If affective responses to exercise, assessed in real time in participants' natural environments, are shown to predict adherence to the walking program, this will signal the need for greater attention to affective variables in health behavior models and as targets of health promotion interventions. PUBLIC HEALTH RELEVANCE: For overweight and obese adults, self-paced exercise may be more pleasurable and easier to maintain than exercise prescribed at moderate intensity (e.g., brisk walking), thus leading to better adherence and thereby better health outcomes. In this study we will compare adherence rates to self-paced exercise versus prescribed moderate intensity exercise among sedentary, overweight and obese adults. We will also ask participants to rate their feelings during each exercise session, using handheld electronic diaries, to determine whether these feelings are related to adherence to the walking program.