NURSE-GUIDED EXERCISE PROTOCOL FOR MINORITY WOMEN

久坐不动和肥胖威胁着近三分之一美国女性的心血管健康。少数族裔女性患肥胖症的风险特别大，与白人女性相比，她们的体力活动往往较少。社区治疗计划中的护士认识到体育锻炼在体重管理中的重要性，但必须依靠实验室试验和跑步机数据来准确指导体育锻炼的建议。对体力活动的剂量-反应效应的研究表明，当久坐不动的人开始锻炼时，冠心病的发病率下降最显著。超重久坐女性在社区人行道或田径跑道上进行的低强度运动的剂量反应和可取性尚未确定。问题是制定一种运动方案，强度足够低，少数族裔妇女在该水平上坚持运动的可能性很高，但强度足够大，对冠心病的有益影响是有效的。具体目的是：1：比较墨西哥裔美国女性和非裔美国女性低强度和中等强度运动对血脂、脂肪细胞大小和功能、低密度脂蛋白颗粒大小、体脂和脂肪分布以及运动耐量的影响。2：确定低强度和中等强度运动对久坐不动的肥胖少数民族女性运动维持的影响。3.探讨运动量与血清总胆固醇、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、体脂、脂肪细胞大小、脂肪分解、低密度脂蛋白颗粒大小、运动耐量之间的剂量-反应关系。将采用两个试验组。两个随机分组每周步行4天，每天30分钟。第一组将以目标心率的40%步行；第二组将以目标心率的65%步行。这项研究的独特之处在于，它提出了一种跨学科的方法来理解支持运动的生物行为机制及其与脂肪代谢的关系。这项研究完成后，将回答某些问题：在低于已知的降低冠心病风险的水平下进行48周的锻炼是否会在这些风险因素中产生显著变化？而且，锻炼的剂量(频率)是否会对身体成分、血脂、脂肪细胞大小和功能所衡量的危险因素产生分级影响？

Sedentary activity and obesity threaten the cardiovascular health of nearly one third of U.S. women. Minority women are at particular risk for obesity and tend to engage in less physical activity than their white counterparts. Nurses in community- based treatment programs recognize the importance of physical exercise in weight management, but must rely on laboratory trials and treadmill data to accurately guide recommendations of physical activity. Examinations of the dose-response effect of physical activity have demonstrated that the most significant reductions in rates of CHD are found when sedentary individuals begin to exercise. The dose-response and desirability of low intensity exercise, performed on community sidewalks or field tracks by overweight sedentary women, have not been established. The problem is to develop an exercise protocol that is of low enough intensity that the probability of minority women sustaining exercise at that level is high, yet is of sufficient intensity to be effective with respect to beneficial effects of CHD. The Specific Aims are to: 1: Compare the effects of low and moderate intensity of exercise in Mexican American and African American women on blood lipids, fat cell size and function, LDL particle size, body fatness and fat distribution, and exercise tolerance. 2: Determine the effects of low and moderate intensity of exercise on exercise maintenance in sedentary, obese minority women. 3; Explore the dose-response relationship of exercise volume, where volume is an interaction term of intensity X maintenance, to total serum cholesterol, triglycerides, HDL-C, LDL-C, body fatness, fat cell size, lipolysis, LDL particle size, and exercise endurance. Two experimental groups will be employed. Both randomized groups will walk 4 days a week, for 30 minutes a day. Group 1 will walk at 40 percent of target heart rate; Group 2 will walk at 65 percent of their target heart rate. This study is unique in that is proposes an interdisciplinary approach to the understanding of the biobehavioral mechanism underpinning exercise and its relationship to fat metabolism. This study, when completed, will answer certain questions: can exercise of a 48 week duration at levels below those known to decrease CHD risk produce significant changes in those risk factors? and, will the dose (frequency) of exercise produce a graded effect on the risk factors as measured by body composition, blood lipids, and fat cell size and function?