Dietary Nitrate and Muscle Power With Aging
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 47
- 试验地点
- 2
- 主要终点
- Maximal Knee Extension Velocity
研究概览
简要总结
The purpose of this study is to see if drinking beetroot juice (BRJ) is beneficial for aging patients. We hope to determine the effect of BRJ on exercise performance. BRJ improves exercise performance in athletes and normal people. We are trying to determine if BRJ improves exercise performance in aging patients. We will be comparing the effects of BRJ versus the effects of a placebo (BRJ without the nitrates that are naturally occurring in beets and other similar foods). It is thought that the benefits of BRJ may come from its natural nitrate content. Although BRJ is available for purchase in grocery stores, for the purposes of this study it is considered investigational, which means that it has not been approved as a medical therapy.
详细描述
This study consists of two parts separated by a 14 day wash-out. Subjects will be randomly assigned to receive either the BRJ or placebo during the first part. During the second part they will receive the opposite of what they had during the first part. This is considered a double-blind study, which means neither the subjects nor the investigators will know what form (BRJ or placebo) a subject is receives.
Study Visit One (Screening) 1-2 hours
The purpose of the screening visit is to explain all aspects of the study. It will also determine if subjects can participate in the study. Subjects will provide a complete medical history and undergo a physical exam. They will have their blood drawn (about 1.5 teaspoons) and provide a urine sample. They will also practice the entire neuromuscular function exercise test. During this test, the strength of their muscles will be determined by having them kick, push and/or pull back as hard as you can while their leg is strapped to an exercise device. A vital signs monitor will measure your blood pressure, heart rate, and rhythm.
During the remainder of the study subjects will be instructed to consume their normal diet. However, they will be asked to avoid eating foods high in nitrate such as beets, spinach, and collard greens the evening before each visit. They will be asked to refrain from the use of antibacterial mouthwash, such as Listerine or Cepacol, during the study. Chewing gum, alcohol, and food and drinks containing caffeine (coffee, tea, chocolate, and soft drinks) should be avoided 24 hours prior to each visit. They will be asked to fast for 12 hour prior to each study visit.
Study Visit Two - Approximately 5 hours
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Triple (Participant, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 65 Years 至 79 Years（Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •In good health, as determined by the investigator's review of history (provided by subject at screening visit), physical examination, and routine blood and urine tests (done at screening visit)
排除标准
- •Men and women <65 or >79 years of age
- •Unable to provide informed consent
- •Currently pregnant or lactating (given the age range for the study, verbal confirmation by subject is believed to be sufficient)
- •Current smokers
- •Significant orthopedic limitations or other contraindications to strenuous exercise
- •Those taking phosphodiesterase inhibitors (e.g., Viagra)
- •Those taking proton pump inhibitors, antacids, xanthine oxidase inhibitors, or on hormone replacement therapy
- •Those taking anti-coagulants (e.g., Coumadin) or on anti-platelet therapy
- •History of neuromuscular disease (e.g., cervical spondylotic radiculomyelpathy, lumbar spondylosis, amyotrophic lateral sclerosis, Guillain-Barré syndrome, and acquired demyelinating polyneuropathies), cardiovascular disease (e.g., > stage I hypertension, heart failure, myocardial infarction/ischemia, significant myocardial or pericardial diseases (e.g. amyloidosis, constriction), moderate or severe valvular disease, renal disease, liver disease, or anemia
研究组 & 干预措施
nitrate
干预措施: nitrate (Dietary Supplement)
结局指标
主要结局
Maximal Knee Extension Velocity
时间窗: 14 days
\*Maximal\* knee extension velocity was determined by having participants perform knee extensions at velocities of 0, 1.57, 3.14, 4.57, and 6.14 rad/s on an isokinetic dynamometer (device that controls velocity while measuring torque). Peak power at each velocity was calculated by multiplying the measured torque by that velocity, then \*maximal\* knee extensor velocity was determined by fitting a parabolic function to these data (\*maximal\* knee extension velocity = 2 x fitted velocity at which \*maximal\* power is developed). Higher values are better.
Muscle Knee Extensor Power
时间窗: 1 day
This outcome was determined by having participants perform knee extensions at velocities of 0, 1.57, 3.14, 4.57, and 6.14 radians per second on an isokinetic dynamometer (device that controls velocity while measuring torque). \*Peak\* power at each velocity was calculated by multiplying the measured torque by that velocity, then a parabolic function was fit to these calculated data to predict \*maximal\* knee extensor power. Higher values are better.
Maximal Knee Extension Power
时间窗: 14 days
\*Maximal\* knee extension power was determined by having participants perform knee extensions at velocities of 0, 1.57, 3.14, 4.57, and 6.14 rad/s on an isokinetic dynamometer (device that controls velocity while measuring torque). \*Peak\* power at each velocity was calculated by multiplying the measured torque by that velocity, then \*maximal\* power was determined by fitting a parabolic function to these data. Higher values are better.
次要结局
未报告次要终点
研究者
Andrew Coggan
Associate Professor
Indiana University