20 YEAR CHANGES IN FITNESS & CARDIOVASCULAR DISEASE RISK

描述（由申请人提供）：尽管与年龄相关的有氧能力下降有很好的文献记载，但体育活动、体脂和遗传变异对变化率的影响尚不清楚。此外，关于成年早期和中期有氧能力变化率如何影响心血管疾病危险因素的发展或亚临床和临床心血管疾病（CVD）相关终点的发生率，我们知之甚少。为了解决这些问题，我们建议在2005年6月开始进行一项辅助研究，同时进行20岁的CARDIA（年轻人冠状动脉风险发展）检查。我们预计，大约有3650名（75%）的非裔美国人和白人男性和女性的幸存成员将返回20年级考试，届时他们将在38-50岁之间。这项拟议的辅助研究的总体目标是了解身体健康、身体活动、体重和组成、脂肪分布、遗传因素之间复杂的纵向关系，以及它们对肥胖、代谢综合征和亚临床心血管疾病发展的独立或相互作用。为了实现这一目标，我们建议对所有20年级的CARDIA参与者进行测量：

DESCRIPTION (provided by applicant): Although an age-related decline in aerobic capacity is well documented, the impact of physical activity, body fat, and genetic variation on the rate of change is not well understood. In addition, little is known about how rate of change in aerobic capacity during early and middle adulthood affects the development of cardiovascular disease risk factors or the incidence of subclinical and clinical cardiovascular disease (CVD) related end-points. We propose to address these issues by conducting an ancillary study in conjunction with the Year 20 CARDIA (Coronary Artery Risk Development in Young Adults) examination, which is scheduled to take place beginning in June, 2005. We anticipate that approximately 3,650 (75%) of the surviving members of the initial cohort of African American and white men and women will return for the Year 20 exam, at which point they will be 38-50 years old. The overall goal of the proposed ancillary study is to understand the complex, longitudinal relations between physical fitness, physical activity, body mass and composition and fat distribution, and genetic factors and their independent or interactive effects on the development of obesity, the metabolic syndrome, and sub-clinical CVD. To accomplish this goal, we propose to measure, on all Year 20 CARDIA participants: 1. Aerobic capacity, by means of a symptom-limited graded exercise treadmill test, using the same protocol as that used in CARDIA at the Year 0 and Year 7 exams; 2. Body composition and fat distribution, using a whole body dual energy x-ray absorptiometery (DEXA) scan; 3. Physical activity, using 7 days of accelerometer recordings; and 4. DNA sequence variants in selected candidate genes associated with cardiorespiratory fitness, components of the metabolic syndrome, and response to regular exercise, using stored DNA. Data from this ancillary study will be combined with core CARDIA examination data to address the following aims: a. Examination of the contribution of body mass and composition, fat distribution, objectively measured physical activity and specific genetic polymorphisms to the variance in Year 20 aerobic capacity and in age-related decline in aerobic capacity over a 20-year time period from young adulthood to mid-life, stratifying by race and gender. b. Longitudinal examination of the effect of aerobic capacity on changes in cardiovascular disease risk factors and on the incidence of CVD-related endpoints (e.g. hypertension, metabolic syndrome, subclinical disease [e.g. coronary artery calcium]). Data from this study should provide information that will help us more deeply understand the interrelationships of cardiorespiratory fitness, body composition, and CVD-related risk factors and endpoints, and may provide the basis for more extensive evidence-based recommendations on the role of fitness in cardiovascular health.