Biological Effects of Weight Loss Plus Exercise in Obese Older African-American Women: An Investigation of Aging-related Changes in Black and White Women
试验速览
- 阶段
- 2 期
- 状态
- 已完成
- 入组人数
- 34
- 试验地点
- 2
- 主要终点
- Performance on the 400 Meter Walk
研究概览
简要总结
Obesity and sedentary lifestyle are associated with physical impairments and biological changes in older adults. Weight loss combined with exercise may reduce inflammation and may improve physical functioning in older adults who are overweight or obese and sedentary. However, the mechanisms by which weight change and exercise influence physical functioning and sarcopenia remain largely understudied. ions). In the WL+E group, participants attended a group-based weight management session plus three supervised exercise sessions each week throughout the entire study. During each exercise session, participants engaged in both aerobic activities (i.e., walking) and lower body resistance training of moderate intensity. The participants in the educational control group attended monthly health education lectures on topics relevant to older adults. It was hypothesized that participants assigned to the WL+E intervention would 1) lose a larger amount of weight, 2) improve their physical function levels, and 3) reduce levels of oxidative stress and inflammation to a greater degree than participants assigned to the Educational Control group. Outcomes are: 1) body weight, 2) walking speed (assessed by 400 meter walk test), 3) the Short Physical Performance Battery [SPPB], and 4) knee extension isokinetic strength. The objectives of this pilot study are fourfold: 1) to demonstrate the feasibility, acceptability, and efficacy of the proposed WL+E intervention in a sample of 40 sedentary, obese older adults with impaired physical functioning; 2) to examine the biological effects of the intervention on inflammatory processes, oxidative stress, apoptosis, sarcopenia, muscle and body composition, muscle strength, and functional performance; 3) to determine whether the expected beneficial effects of the WL+E intervention on physical functioning are mediated by changes in inflammation, apoptosis, and sarcopenia; and 4) to determine the effect size of the WL+E intervention on key outcomes and provide the basis for sample size calculations in the planning of a larger RCT.
详细描述
SPECIFIC AIMS A.1. Overview Obesity is associated with a higher level of inflammation and oxidative stress, which in turn are important mediators of sarcopenia, declines in physical functioning, and physical limitations in older adults. Several observational studies and randomized controlled trials (RCTs) suggest that behavioral interventions targeting weight loss through caloric restriction plus exercise (CR +EX) may reduce inflammation and may improve function in obese older adults.3 The mechanisms by which CR +EX may influence physical functioning and sarcopenia (the involuntary loss of skeletal muscle with age) remain largely understudied. It is proposed that CR +EX may avert sarcopenia by reducing inflammation, oxidative damage, and consequent apoptosis of skeletal muscle myocytes.
A.2. Objective of the Pilot Study
The proposed pilot study will lay the groundwork for a RCT of the effects of CR +EX on inflammation, oxidative stress, apoptosis, body composition, intramuscular fat, sarcopenia, muscle strength, and physical functioning in obese older adults. The specific objectives of the proposed study are as follows:
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Demonstrate the feasibility, acceptability, and efficacy of the proposed intervention, including:
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Ability to recruit 40 sedentary, older obese adults with mild to moderate functional disability;
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High rate of attendance at treatment sessions (Mean > 75%); and
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Good response to treatment (Mean body weight loss > 7%).
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Evaluate the biological effects of the CR +EX intervention, including changes in:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Outcomes Assessor)
入排标准
- 年龄范围
- 55 Years 至 79 Years（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •African American or Caucasian Female
- •Age between 55 - 79 years
- •BMI > 28 kg/m2
- •sedentary lifestyle (defined as < 20 min/week of aerobic exercise)
- •mild to moderate physical impairments (score on the Short Physical
- •Performance Battery between 4 - 10).
排除标准
- •Weight >300 lbs.
- •Weight loss > 10 lbs. within the past 6 months
- •History of surgery for weight loss
- •Hospitalization with the past 6 months
- •Significant underlying disease likely to limit lifespan and/or increase risk of interventions (cancer or any condition with a life expectancy < 5 years with the exception of non-melanoma skin cancer; serious infectious diseases; myocardia infarction, cerebrovascular accident, or unstable angina within the past 6 months; NYHA Class 3 or 4 congestive heart failure; aortic stenosis; chronic hepatitis; cirrhosis; kidney disease; solid organ transplantation; chronic gastrointestinal disorders; fibromyalgia; chronic fatigue syndrome; major psychiatric disorder).
- •Metabolic exclusions (resting blood pressure > 160/90 mmHg, fasting blood glucose > 160 mg/dl, fasting triglycerides > 400 mg/dl; patients on medication for hypertension, diabetes, or hyperlipidemia will not be excluded unless their values suggest "poor control").
- •Medication exclusions (Antipsychotic agents; monoamine oxidase inhibitors; systemic corticosteroids; antibiotics for HIV or TB; chemotherapeutic drugs; or current use of prescription weight-loss drugs).
- •Physical limitations likely to prevent exercise participation (use of walker; breathing problems that limit physical activity).
- •Conditions or behaviors likely to affect the conduct of the trial (e.g., unwilling or unable to give informed consent; unwilling to accept random assignment; likely to move out of area within next 2 years; unable to attend weekly meetings; unwilling to complete paperwork; participation in another randomized research project; unwilling or unable to comply with study requirements or schedule)
- •Contraindications to MRI (MR-incompatible implants or severe claustrophobia).
- •Contraindications to muscle biopsy (i.e., lidocaine allergy)
- •Presence of any other medical condition, which in the opinion of the research staff, would be incompatible with participation in the weight loss plus exercise program.
结局指标
主要结局
Performance on the 400 Meter Walk
时间窗: 24 weeks
Walking speed was assessed at baseline and 24-week assessment by the 400 Meter Walk Test, during which participants were asked to complete a standard walking course at their usual pace. Participants were permitted to stop during the walk but were not allowed to sit or receive help from others and were required to complete the course in 15 minutes.
次要结局
- Body Weight(24 weeks)
- Short Physical Performance Battery(24 weeks)
- Knee Extension Maximum Isokinetic Strength (Weight Lifted in Kilograms).(24 weeks)
- Mitochondrial Function (Cox IV Subunit)(24 weeks)