A Placebo-controlled, Randomized, Double-masked, Cross-over Acute Intervention Study Investigating the Effects of Cocoa Flavanols on Peripheral Endothelial Function in the Context of Prolonged Sitting in Healthy Older Adults
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 20
- 试验地点
- 2
- 主要终点
- Flow-mediated dilatation of the superficial femoral artery
研究概览
简要总结
Sitting time is high in older adults and has been shown to temporarily impair endothelial function and blood pressure. Flavanols, plant-derived compounds, acutely enhance endothelial function and reduce Blood pressure in older adults. The aim of this study is to investigate whether acute ingestion of cocoa flavanols can improve peripheral endothelial function and blood pressure during prolonged sitting in healthy older adults.
In a randomised, double-blinded, cross-over, placebo-controlled human study, 20 healthy older adults will consume either a high-flavanol (695 mg) or low-flavanol (5.6 mg) cocoa beverage immediately before a 2-hour sitting bout. Flow-mediated dilation (FMD) of the superficial femoral (SFA; primary outcome) and brachial (BA) arteries, and blood pressure, were assessed before and after sitting. Microvasculature haemodynamics were assessed in the gastrocnemius before, during, and after sitting. It is hypothesized that the high flavanol cocoa will prevent declines in brachial and superficial femoral Flow-mediated dilatation post sitting.
详细描述
Older individuals are estimated to spend more than 10 hours in their waking day in sedentary activities , which can include sitting bouts lasting up to 5.4 hours/day . Greater sedentary time was found to be associated with a significantly increased risk of cardiovascular diseases and all-cause mortality. Several experimental studies have shown that even just one isolated episode of prolonged sitting (from 1 to 6 hours) has detrimental effects on human endothelial function, as measured by flow-mediated dilation (FMD).
Flavonoid-rich foods are typically consumed in high amounts in cardioprotective diets, with evidence from both observational and Randomised Controlled Trials showing flavonoids to improve biomarkers of cardiovascular health. Flavanols, a sub-group of flavonoids present in unprocessed cocoa, have been extensively shown to act quickly within the vasculature, improving both brachial Flow-mediated dilatation and lower-limb common femoral artery (CFA) Flow-mediated dilatation within 2 hours of intake in older adults.
The aim of the current study is to examine whether acute consumption of cocoa flavanols prior to a 2-hour bout of uninterrupted sitting can be beneficial in improving endothelial function (as measured by Flow mediated dilatation) in the upper-limb Brachial Artery (BA) and lower-limb Superficial Femoral Artery (SFA) in older adults, as well as downstream, muscle microvascular function. We will further investigate whether cocoa flavanols can prevent sitting-induced increases in blood pressure in older adults. We hypothesise that cocoa flavanols would be effective at rescuing upper- and lower-limb Flow-mediated dilatation and improve blood pressure during uninterrupted sitting in older age
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Prevention
- 盲法
- Triple (Participant, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 65 Years 至 —（Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Males and females
- •aged 65 or more
排除标准
- •history or symptoms of cardiovascular, renal, pulmonary, metabolic, or neurologic disease, hypertension (blood pressure higher than 140/90 mm Hg, based on recent guidelines), diabetes mellitus, anaemia, asthma, immune conditions, or high cholesterol.
- •individuals who were on weight-reducing diets
- •individuals taking anticoagulants,
- •had recently undergone prolonged bed-rest periods
- •have been on antibiotics in the previous 3 months
- •have an infection at present (e.g. cold) or viral infection
研究组 & 干预措施
High-flavanol cocoa powder
12 g of fat-reduced natural cocoa powder containing 695 mg of total flavanols, including 150 mg (-)-epicatechin
干预措施: High-flavanol cocoa powder (Dietary Supplement)
Low-flavanol cocoa powder
12 g of fat-reduced alkalized cocoa powder containing 5.6 mg of total flavanols
干预措施: Low-flavanol cocoa powder (Dietary Supplement)
结局指标
主要结局
Flow-mediated dilatation of the superficial femoral artery
时间窗: Change from pre-intervention baseline to 2 hours post intervention /2 hours post sitting
Flow-mediated dilatation (FMD) of the superficial femoral artery. Expressed as percent FMD: change in brachial diameter from baseline to peak dilation following 5 minutes of arterial occlusion. Brachial artery diameter and blood flow will be measured using Doppler ultrasonography (uSmart 3300, Terason).
Flow-mediated dilatation of the superficial femoral artery
时间窗: Change from pre-intervention baseline to 2 hours post intervention /2 hours post sitting
Flow-mediated dilatation (FMD) of the superficial femoral artery. Expressed as percent FMD: change in brachial diameter from baseline to peak dilation following 5 minutes of arterial occlusion. Brachial artery diameter and blood flow will be measured using Doppler ultrasonography (uSmart 3300, Terason).
次要结局
- Flow-mediated dilatation of the brachial artery(Change from pre-intervention baseline to 2 hours post-intervention/ 2hours post sitting)
- Tissue oxygenation index (TOI) of Gastrocnemius skeletal muscle(Change from pre-intervention baseline to 2 hours post-intervention / 2 hours of sitting)
- Normalized haemoglobin index (nTHI) of the gastrocnemius skeletal muscle(Change from pre-intervention baseline to 2 hours post-intervention/2 hours sitting)
- Tissue oxygenation index (TOI) of Gastrocnemius skeletal muscle during 2 hours of sitting(Post-intervention time points considered during sitting were 0 , 10 , 60 and 120 minutes.)
- Normalized haemoglobin index (nTHI) of Gastrocnemius skeletal muscle during 2 hours of sitting(Post-intervention time points considered during sitting were 0 min , 10 min, 60 min and 120 min.)
- Brachial Systolic Blood Pressure (SBP)(Change from pre-intervention baseline to 2 hours post-intervention / 2 hours of sitting)
- Flow-mediated dilatation of the brachial artery(Change from pre-intervention baseline to 2 hours post-intervention/ 2hours post sitting)
- Tissue oxygenation index (TOI) of Gastrocnemius skeletal muscle(Change from pre-intervention baseline to 2 hours post-intervention / 2 hours of sitting)
- Normalized haemoglobin index (nTHI) of the gastrocnemius skeletal muscle(Change from pre-intervention baseline to 2 hours post-intervention/2 hours sitting)
- Tissue oxygenation index (TOI) of Gastrocnemius skeletal muscle during 2 hours of sitting(Post-intervention time points considered during sitting were 0 , 10 , 60 and 120 minutes.)
- Normalized haemoglobin index (nTHI) of Gastrocnemius skeletal muscle during 2 hours of sitting(Post-intervention time points considered during sitting were 0 min , 10 min, 60 min and 120 min.)
- Brachial Systolic Blood Pressure (SBP)(Change from pre-intervention baseline to 2 hours post-intervention / 2 hours of sitting)
- Brachial Diastolic Blood Pressure (DBP)(Change from pre-intervention baseline to 2 hours post-intervention / 2 hours of sitting)
- Heart Rate(Change from pre-intervention baseline to 2 hours post-intervention/2 hours sitting)
- Resting Superficial Femoral Artery Blood Flow(Change from pre-intervention baseline to 2 hours post-intervention/2 hours sitting)
- Resting Brachial Artery Blood Flow(Change from pre-intervention baseline to 2 hours post-intervention/2 hours sitting)
- Superficial Femoral Artery Shear Rate(Change from pre-intervention baseline to 2 hours post-intervention/2 hours sitting)
- Brachial Artery Shear Rate(Change from pre-intervention baseline to 2 hours post-intervention/2 hours sitting)