DOSE RESPONSE TO EXERCISE AND CARDIOVASCULAR HEALTH

描述：（改编自研究者摘要）该项目是 旨在确定必要的最小体力活动剂量， 改善心血管健康。 更具体地说，这四年 本研究将对500名健康男女进行有氧训练和评价， 30-65岁。 最小和最佳的强度和频率 必要的运动，以引起心血管疾病的显着改善 健康将被确定。 这些计划还包括评估影响 特定剂量的运动对收缩压和舒张压的降低 血压和HDL-胆固醇升高（主要结局）， 除了身体活动水平的变化，有氧健身（VO 2 最大值）、身体成分（%脂肪和腰臀比）、甘油三酯，以及 LDL-胆固醇（次要结局）。 心理变量（抑郁， 焦虑，愤怒和感知压力）和健康相关的生活质量 也将被评估，坚持锻炼的重要问题 将检查运动剂量的影响。 科目 将被随机分配到5组之一，采用2x2析因设计加 常规护理对照组（5组，每组100例）。 受试者将接受 中度（45-55%）或高度（最大心率储备的65-75%） 强度，并且以3-4或5-7天/周的频率（即，第1组，65- 75%@ 5-7 d/wk;组2，65-75%，3-4 d/wk;组3，45-55%，5-7 d/wk;组4， 45- 55%@3 -4 d/wk;以及，第5组，常规护理对照）。 控件将接收 医生建议增加他们的体力活动。 受试者 第1-4组的受试者将参与使用步行作为 培训时间为24个月。 一种生活方式模式， 将使用体力活动，因为受试者可以积累锻炼 以10分钟为增量或更连续的时间（对于 总时长30分钟/天），并在 对受试者最方便（即在家、工作或某种组合 其中）。 测试将在基线（0）、12和24个月时进行。 干预 该应用程序假定组1-4将显示 收缩压和舒张压显著降低， 与常规护理对照组相比，HDL-胆固醇增加。 它 进一步表明，将有显着的主要影响， 频率和强度，每一个更高的水平产生更大的 与较低水平相比，主要结果变量有所改善 每个剂量。 该研究还计划确定最小剂量反应 进行必要的锻炼，以显著改善心血管疾病 和行为健康因素。 最后，该项目包括审查 年龄和初始测试值水平对结果变量的影响， 确定他们的相互作用是否影响干预的结果。 的 拟议研究的结果将提供有关 改善心血管健康所需的运动剂量，如NIH 关于身体活动和CV健康的共识会议，以及最近的 外科医生的报告。

DESCRIPTION: (Adapted from Investigator's Abstract) This project is designed to determine the minimal dose of physical activity necessary to improve cardiovascular (CV) health. More specifically, this 4-year investigation will evaluate and aerobically train 500 healthy men and women, 30-65 years of age. Both the minimal and optimal intensity and frequency of exercise necessary to elicit significant improvements in cardiovascular health will be determined. The plans also include assessment of the effect of specific doses of exercise on the reduction in systolic and diastolic blood pressure and increase in HDL-cholesterol (primary outcomes), in addition to changes in levels of physical activity, aerobic fitness (VO2 max), body composition (% fat and waist-to-hip ratio), triglycerides, and LDL-cholesterol (secondary outcomes). Psychological variables (depression, anxiety, anger, and perceived stress) and health-related quality of life will also be evaluated, and the important issue of adherence to exercise will be examined with respect to the effect of dose of exercise. Subjects will be randomized into one of 5 groups in a 2x2 factorial design plus a usual care control group (n=100 in each of 5 groups). Subjects will train at a moderate (45-55%) or high (65-75% of maximum heart rate reserve) intensity, and at a frequency of 3-4 or 5-7 days/wk (viz., Group 1, 65-75% @ 5-7 d/wk; Group 2, 65-75% @ 3-4 d/wk; Group 3, 45-55% @ 5-7 d/wk; Group 4, 45-55% @ 3-4 d/wk; and, Group 5, usual care control). Controls will receive advice from a physician to increase their physical activity. The subjects in Groups 1-4 will participate in an exercise intervention using walking as the mode of training for a total of 24 months. A lifestyle model of physical activity will be used, in that subjects can accumulate exercise minutes during the day in 10-min increments or more continuously (for a total duration of 30 min/day), and training will be conducted where it is most convenient for the subject (i.e. at home, work or some combination thereof). Tests will occur at baseline (0), 12, and 24 months of the intervention. The application posits that Groups 1-4 will show a significant reduction in systolic and diastolic blood pressure and an increase in HDL-cholesterol compared to the usual care control group. It further suggests that there will be significant main effects for both frequency and intensity, with the higher levels of each producing greater improvement on the major outcome variables compared to the lower levels of each dose. The study is also planned to determine the minimal dose response to exercise necessary to elicit significant improvement in cardiovascular and behavioral health factors. Finally, the project includes examination of the effects of age and level of initial test values on outcome variables to determine if their interactions affect the results of the intervention. The results from the proposed study will provide important data regarding the dose of exercise required to improve CV health, as described both by the NIH Consensus Conference on Physical Activity and CV Health and by the recent Report of the Surgeon General.