8 Weeks of L-Citrulline Supplementation to Improve Low-intensity Resistance Exercise Training Vascular Adaptations in Postmenopausal Women With Hypertension
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 29
- 试验地点
- 2
- 主要终点
- Changes in endothelial function via brachial artery flow-mediated dilation (effects of L-Citrulline only)
研究概览
简要总结
The overall objective of this project is to bring forth evidence that L-Citrulline (L-CIT) supplementation and low intensity resistance exercise training (LIRET) alone and combined will improve vascular function and muscle fitness (mass, strength, and exercise performance) in postmenopausal women with hypertension. The investigators' central hypothesis is that adjuvant L-CIT supplementation may synergistically enhance vascular (arterial stiffness, BP, muscle oxygenation, blood flow) and muscular (strength, exercise performance) responses to LIRET in postmenopausal women with hypertension by improving endothelial vasodilatory function.
详细描述
Individuals who are on medications will refrain from use the morning of all laboratory visits. Participants will be asked to bring medications with them, and will be allowed to ingest it after the vascular measurements have been obtained.
There will be a total of 7 laboratory visits. The 1st visit will be approximately 1 hr and 45 minutes. The 2nd and 3rd visit will be approximately 2 hrs. The 4th and 6th visit will total about 2 hrs and 15 minutes and finally, the 5th and 7th visit will total about 1hr and 15 minutes. This means the total participant time for laboratory visits will be approximately 12 hours. In addition to this, the second 4 weeks of the 8 week study period will involve coming to the Kinesiology and Sport Management building at Texas Tech University main campus 3 times per week to perform the low-intensity resistance training intervention. These visits should last no more than 30-45 minutes.
The first 3 visits will be separated by 48-72 hrs. Visits 3 and 4 will be separated by 4 weeks (first 4 weeks of LCIT or Placebo supplementation). Visits 4 and 5 will be separated by 48-72 hours. Visits 5 and 6 will again be separated by 4 weeks (Second 4 weeks of LCIT or Placebo supplementation with the addition of Low-intensity resistance exercise in both groups).
Approximately 12 hours total for each of the 7 laboratory visits, as well as 30-45 minutes 3 times per week during the last 4 weeks of the 8 week study.
Using a parallel placebo-controlled design, postmenopausal women with elevated blood pressure or hypertension will be randomized to receive L-CIT supplementation (10g/day) alone for 4 weeks, followed by 4 weeks of L-CIT supplementation in combination with low-intensity resistance training or placebo (maltodextrin) alone for 4 weeks, followed by 4 weeks of placebo in combination with low-intensity resistance training.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Double (Participant, Investigator)
盲法说明
Double-blind, randomized, parallel, placebo-controlled
入排标准
- 年龄范围
- 50 Years 至 75 Years（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Women aged 50-75 years
- •Resting systolic BP 120-159 mmHg
- •Sedentary (< 60 min of exercise/week)
- •Body mass index of 18.5-39.9 kg/m2)
- •Fasting glucose < 126 mg/dL
- •HbA1c < 6.4%.
排除标准
- •Body mass index ≥ 40 or < 18.5 kg/m2
- •Diagnosed with type 1 or 2 diabetes mellitus
- •Cardiovascular diseases
- •Systolic blood pressure > 170 mmHg or on more than two anti-hypertensive medication
- •Other chronic diseases such as cancer, asthma, glaucoma, thyroid, kidney, liver and pancreatic disease
- •Individuals incorporated in a weight loss program and aerobic or resistance training program
- •Heavy smokers (> 20 cigarettes per day)
- •Heavy drinkers (> 12 alcoholic drinks per week)
结局指标
主要结局
Changes in endothelial function via brachial artery flow-mediated dilation (effects of L-Citrulline only)
时间窗: 4 weeks
Endothelial function will be assessed at baseline and after 4 weeks of L-Citrulline supplementation alone using brachial artery flow-mediated dilation. All measurements will be performed using Doppler ultrasound.
Changes in arm exercise blood flow (effects of L-Citrulline only)
时间窗: 4 weeks
Blood flow will be measured in the brachial artery during low intensity arm exercise. All measurements will be performed using Doppler ultrasound.
Changes in arm exercise blood flow (effects of L-Citrulline combined with low-intensity resistance exercise training)
时间窗: 4 weeks
After the 4-week assessment, blood flow will be measured in the brachial artery during low intensity arm exercise. All measurements will be performed using Doppler ultrasound.
Changes in leg exercise blood flow (effects of L-Citrulline combined with low-intensity resistance exercise training)
时间窗: 4 weeks
After the 4-week assessment, blood flow will be measured in the superficial femoral artery during low intensity leg exercise. All measurements will be performed using Doppler ultrasound.
Changes in endothelial function via superficial femoral artery flow-mediated dilation (effects of L-Citrulline only)
时间窗: 4 weeks
Endothelial function will be assessed at baseline and after 4 weeks of L-Citrulline supplementation alone using superficial femoral artery flow-mediated dilation. All measurements will be performed using Doppler ultrasound.
Changes in endothelial function via brachial artery flow-mediated dilation (effects of L-Citrulline combined with low-intensity resistance exercise training)
时间窗: 4 weeks
After the 4-week assessment, endothelial function will be assessed after 4 additional weeks of L-Citrulline supplementation with combined low-intensity resistance exercise training with the legs using brachial artery flow-mediated dilation. All measurements will be performed using Doppler ultrasound.
Changes in endothelial function via superficial femoral artery flow-mediated dilation (effects of L-Citrulline combined with low-intensity resistance exercise training)
时间窗: 4 weeks
After the 4-week assessment, endothelial function will be assessed after 4 additional weeks of L-Citrulline supplementation with combined low-intensity resistance exercise training with the legs using superficial femoral artery flow-mediated dilation. All measurements will be performed using Doppler ultrasound.
Changes in leg exercise blood flow (effects of L-Citrulline only)
时间窗: 4 weeks
Blood flow will be measured in the superficial femoral arteries during low intensity leg exercise. All measurements will be performed using Doppler ultrasound.
次要结局
- Quantification of endothelin-1 (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Changes in arterial stiffness via arm, leg, and aortic pulse wave velocity (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Changes in aortic hemodynamics using pulse wave analysis (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Changes in brachial and aortic blood pressure via automated sphygmomanometry (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Changes in muscle strength (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Quantification of nitric oxide (effects of L-Citrulline only)(4 weeks)
- Quantification of Endothelin-1 (effects of L-Citrulline only)(4 weeks)
- Changes in aortic hemodynamics using pulse wave analysis (effects of L-Citrulline only)(4 weeks)
- Quantification of nitric oxide (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Quantification of L-Arginine (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Quantification of arginase (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Quantification of L-Ornithine (effects of L-Citrulline combined with low-intensity resistance exercise training)(4 weeks)
- Changes in arterial stiffness via arm, leg, and aortic pulse wave velocity (effects of L-Citrulline only)(4 weeks)
- Changes in muscle strength (effects of L-Citrulline only)(4 weeks)
- Quantification of L-Arginine (effects of L-Citrulline only)(4 weeks)
- Changes in brachial and aortic blood pressure via automated sphygmomanometry (effects of L-Citrulline only)(4 weeks)
- Quantification of Arginase (effects of L-Citrulline only)(4 weeks)
- Quantification of L-Ornithine (effects of L-Citrulline only)(4 weeks)
研究者
Arturo Figueroa
Arturo Figueroa, Principal Investigator
Texas Tech University