Effect of fat loss on functional and cardiovascular benefits of aerobic exercise

减脂对有氧运动功能和心血管益处的影响

• 批准号: 8319564
• 负责人: Barbara J Nicklas
• 金额: $ 69.5万
• 依托单位: WAKE FOREST UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-04 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8319564
• 关键词: Abdomen; Adult; Advocate; Aerobic; Aerobic Exercise; Affect; Aging; Blood Pressure; Body Weight decreased; Body fat; Caloric Restriction; Cardiovascular system; Clinical; Data; Dose; Educational Intervention; Elderly; Energy Intake; Exercise; Exercise Tolerance; Fatty acid glycerol esters; Goals; Health; High Prevalence; Individual; Intervention; Knowledge; Lead; Lipids; Location; Muscle; Myocardium; Obesity; Organ; Outcome; Participant; Pericardial body location; Physiological Adaptation; Population; Public Health; Randomized; Randomized Clinical Trials; Randomized Controlled Trials; Recommendation; Risk; Risk Factors; Sampling; Skeletal Muscle; Stimulus; Testing; Training; Training Programs; Uncertainty; Visceral; Walking; Weight; Woman; age related; arm; blood lipid; cardiovascular disorder risk; clinical practice; design; disability; experience; fitness; functional decline; glucose tolerance; high risk; improved; inflammatory marker; men; programs; prospective; randomized trial; response; sedentary

DESCRIPTION (provided by applicant): Aging is associated with declines in aerobic capacity, exercise tolerance, and functional endurance that lead to physical disability. To date, regular exercise is the only therapy to consistently improve aerobic function, and perhaps delay the onset of disability. However, some data show that the maximal efficacy of exercise for improving aerobic function is blunted by obesity. In addition, our preliminary data show a potential dose-response benefit of concomitant fat loss on exercise-induced improvements in aerobic function. Thus, combining an exercise intervention with caloric restriction resulting in fat loss may be more efficacious for improving aerobic function than exercise alone in obese elderly, a population at high risk for disability. This study is a 3-arm, 5-month randomized, clinical trial in 180 older (65-79 yrs), obese (BMI=30-34.9 kg/m2), sedentary men and women designed to determine whether the amount of fat loss (achieved through controlled underfeeding) affects the magnitude of improvement in aerobic function (maximal aerobic capacity and endurance) in response to a standardized exercise training stimulus that follows current recommendations. Participants will be randomized to an exercise training intervention (moderate-intensity treadmill walking, 4 d/wk) alone (EX Only), exercise with moderate caloric restriction (-250 kcal/d deficit) designed for low fat loss (EX+Low CR; ~3.4 kg fat loss), or exercise with intensive caloric restriction (-750 kcal/d deficit) designed for high fat loss (EX+High CR; ~10.2 kg fat loss). The Specific Aims are to determine the effects of adding moderate and intensive caloric restriction to a standardized aerobic exercise training intervention on: 1) maximal aerobic capacity and walking endurance (6-minute walking distance); 2) cardiovascular disease risk factors (inflammatory markers, blood lipids, blood pressure, glucose tolerance and endothelial function); and 3) inter- muscular, abdominal visceral and pericardial fat volumes. We will also determine whether improvements in aerobic function and CVD risk factors are related to the degree of total and regional fat loss. If our hypotheses are confirmed, this study will provide the first prospective and definitive evidence from a randomized, controlled trial that loss of fat mass augments exercise-induced improvements in aerobic function. These findings will provide persuasive evidence that addition of caloric restriction to an exercise intervention in older, obese adults may be more effective for improving aerobic function than exercise alone, and are likely to change traditional reluctance to recommend some caloric restriction during an exercise program in older adults for the purpose of maximizing their exercise efforts. In addition, by assessing lipid accumulation around visceral organs, and skeletal and cardiac muscle, before and after the interventions, we will also be able to determine the contribution of fat loss in these local depots to the magnitude of exercise-induced improvement in both functional and CVD risk factor outcomes. PUBLIC HEALTH RELEVANCE: This study will determine whether older, obese men and women who lose more fat during an exercise training program will experience greater improvements in fitness and endurance as a result of the exercise training than those who do not lose any fat, or very little fat. This knowledge could lead to a stronger clinical recommendation for inclusion of weight loss to benefit obese, older individuals who exercise. The results will also provide information on whether the location of fat loss is important for improving fitness and cardiovascular disease risk.

描述（由申请人提供）：衰老与有氧能力，运动耐受性和导致身体残疾的功能耐力的下降有关。迄今为止，定期运动是唯一一贯改善有氧功能并延迟残疾发作的疗法。但是，一些数据表明，改善有氧功能的运动的最大疗效被肥胖削弱了。此外，我们的初步数据表明，伴有脂肪损失对运动引起的有氧功能改善的潜在剂量反应益处。因此，将运动干预与热量限制结合起来，导致脂肪损失可能比单独的肥胖老年人的运动更有效地改善有氧运动，这是残疾人的高风险。这项研究是一项3臂，5个月的随机临床试验，年龄较大（65-79岁），肥胖（BMI = 30-34.9 kg/m2），久坐的男人和女性旨在确定降低脂肪量（通过喂养不足的情况下实现的脂肪量）是否会影响到促进能力的刺激量是否会影响Airobic Aerbic Aerbic Aerobic Aerobic Aerobic and Aribic and Alobic Aerobic and Alobic Aerobic and Aloobic anderobic and and Alobic Aerobic andirobic Aerobic and n e andir airbic and and nater的量当前的建议。参与者将单独进行运动训练干预（中等强度的跑步机步行，4 d/wk）（仅EX），具有中等热量限制的运动（-250 kcal/d赤字）设计用于低脂肪损失（EX+Low CR; 〜3.4 kg; 〜3.4 kg脂肪; 〜3.4 kg脂肪损失），或进行严格的热量限制（-750 kccal/d cr损失），高度损失（-750 kcal/d flow），高度易于损失（+after flow）+（+flow）+（+）高度损失（+）。具体目的是确定在标准的有氧运动训练干预措施中增加中等和密集的热量限制的影响：1）最大有氧运动能力和步行耐力（步行6分钟）； 2）心血管疾病危险因素（炎症标记，血脂，血压，葡萄糖耐受性和内皮功能）； 3）肌肉间，腹部内脏和心包脂肪体积。我们还将确定有氧功能和CVD风险因素的改善是否与总脂肪损失的程度有关。如果我们的假设得到了证实，则该研究将提供第一个前瞻性和确定性的证据，从一项随机，对照试验中，脂肪质量损失增加了运动引起的有氧功能的改善。这些发现将提供有说服力的证据，表明对年长的，肥胖的成年人进行运动干预的热量限制可能比单独锻炼更有效，并且很可能会改变传统的不愿意在老年人的运动计划中推荐一些热量限制，以最大程度地提高其运动努力。此外，通过评估干预措施之前和之后的内脏器官以及骨骼和心脏肌肉周围的脂质积累，我们还将能够确定这些局部仓库中脂肪损失对功能性和CVD风险因素的改善的幅度的贡献。 公共卫生相关性：这项研究将确定在运动训练计划中失去更多脂肪的年长，肥胖的男人是否会因运动训练而在健身和耐力方面的改善比没有失去任何脂肪或很少脂肪的人会得到更大的改善。这些知识可能会导致更强有力的临床建议，以包括减肥以使肥胖的年龄较大的人受益。结果还将提供有关脂肪损失位置是否对改善健身和心血管疾病风险重要的信息。