Diet and Whole-body Vibration Training on Cardiovascular and Autonomic Function

The Effect of Diet and Whole-body Vibration Training on Cardiovascular and Autonomic Function in Obese Postmenopausal Women

Obesity is a major risk factor for premature arterial abnormalities including high blood pressure and increased stiffness. Previous studies have shown that weight loss via lifestyle modifications is associated with a decrease in large artery (aorta) stiffness. However, along with decreases in fat mass, hypocaloric diet reduces muscle mass. Whole body vibration results in similar increases in muscle mass and strength than those observed after resistance exercise and is feasible for special populations such as the obese and the elderly.

The investigators hypothesis is that weight loss via diet combined with whole body vibration training would additively reduce arterial stiffness and blood pressure in obese women. The investigators also hypothesize that the improved arterial function with weight loss would be associated with beneficial changes in the main mechanisms involved in BP regulation.

Study Overview

• Status: Completed
• Conditions: Hypertension; Obesity; Pre-hypertension
• Intervention / Treatment: Other: Hypocaloric diet; Other: Whole body vibration training & diet; Other: Whole Body Vibration Training

Detailed Description

The purpose of the study is to examine the effects of 12 weeks of whole body vibration training (WBVT) and diet on arterial function, autonomic function, and body composition in obese women. Specific aims of the study are to:

To evaluate the extent to which diet and (WBVT) will improve body composition assessed by changes in fat mass and lean mass using dual-energy x-ray absorptiometry and waist circumference.

To investigate that combined diet and (WBVT) are more efficacious than either treatment alone in ameliorating cardiovascular disease risk factors by assessing arterial stiffness (aortic, systemic, and leg), aortic BP and wave reflection, and autonomic function (heart rate variability, vascular sympathetic activity [low-frequency power of systolic BP variability], and baroreflex sensitivity). Flow mediated dilation and circulating levels of adipocytokines (adiponectin and leptin) and endothelial-derived vasodilators (NO metabolites [NOx], 6-keto PGFIa, insulin, and ghrelin) and vasoconstrictors (endothelin-1 [ET-1],8-iso PGF2a,vascular endothelium growth factor [VGEF]) will be assessed as secondary outcome variables.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Florida
    • Tallahassee, Florida, United States, 32306
      • Florida State University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 45 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Female
• 45 to 65 years of age
• At least 1 year after menopause
• Body mass index of 27-39.9
• Sedentary or low active (less than 2 hr per wk)

Exclusion Criteria:

• Younger than 45 or older than 65 years of age
• Body mass index lower than 27, or 40 or higher
• Physically active or competitively active
• Smoker
• Use of hormone replacement therapy of less than 1 yr
• Use of calcium channel blocker or beta blockers
• Use dietary supplementations (e.g.,L-arginine,L-citrulline,antioxidants)
• Uncontrolled diabetes
• Any restriction that would significantly interfere with compliance with the diet (e.g., allergy to nuts or dairy, or need to avoid soy)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Hypocaloric diet; This arm involves 12 wk of the standard Nutrisystem foods plan complemented by fresh produce and dairy. Subjects consume breakfast, lunch, dinner, and one (women) or two (men) snacks per day.	Other: Hypocaloric diet; The hypocaloric diet intervention consists of 12 wk of the standard Nutrisystem foods plan complemented by fresh produce and dairy. Subjects consume breakfast, lunch, dinner, and one (women) or two (men) snacks per day.
No Intervention: Control; This arm involves not making any change to the subject's lifestyle at the moment of the start of the intervention and for 12 wk.
Experimental: Whole body vibration training & diet; Lower-body exercise training on a vibration platform and diet	Other: Whole body vibration training & diet; Combination of whole body vibration training and hypocaloric diet
Experimental: Whole body vibration training; Lower-body exercises 3 times per wk for 12 wk in a vibration platform	Other: Whole Body Vibration Training; The Whole body vibration training intervention consists of lower-body exercise in a vibration platform 3 times per wk for 12 wk. The subjects will perform static and dynamic exercises for the legs on the vibration platform. Dynamic exercises will be performed with slow controlled movements starting from an upright position into a 60 degree knee flexion (squat) and maximal heel elevation (toestand). Static exercises will be performed without movement in the joint angles described previously. The training volume will increase progressively over the 12-week training period by increasing the intensity of vibration, duration of the exercise set (30-60 sec), number of sets per exercise, and total duration of the training session, and decreasing the duration of rest periods (30-60 sec).The intensity of vibration and amplitude will also be increased progressively (25-30 Hz of frequency and from low to high amplitude).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body Composition	By measuring fat mass and lean soft tissue mass from dual-energy x-ray absorptiometry and waist circumference	12 weeks
Blood pressure	Non-invasive measures of brachial and aortic blood pressure	12 weeks
Arterial Stiffness	Using pulse wave velocity of the aorta, systemic, and legs	12 weeks
Pressure Wave Reflection	Using the augmentation index from radial tonometry	12 weeks
Autonomic Function	Heart rate variability, vascular sympathetic activity [low-frequency power of systolic BP variability], and spontaneous baroreflex sensitivity will be assessed from electrocardiogram and beat-by-beat digital blood pressure	12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Endothelial Function	By measuring circulating levels of adipocytokines (adiponectin and leptin) and endothelial-derived vasodilators (NOx, 6-keto PGFIa, insulin, and ghrelin)and vasoconstrictors (ET-1 and 8-iso PGF2a, VEGF)	12 weeks

Collaborators and Investigators

• Sponsor: Florida State University
• Collaborators: Nutrisystem, Inc.

Study record dates

Study Major Dates

• Study Start: September 1, 2011
• Primary Completion (Actual): April 1, 2012
• Study Completion (Actual): April 1, 2012

Study Registration Dates

• First Submitted: December 3, 2012
• First Submitted That Met QC Criteria: December 3, 2012
• First Posted (Estimate): December 5, 2012

Study Record Updates

• Last Update Posted (Estimate): December 5, 2012
• Last Update Submitted That Met QC Criteria: December 3, 2012
• Last Verified: December 1, 2012

More Information

Terms related to this study

• Keywords: obesity; hypertension; autonomic function; pulse wave velocity; endothelial function; arterial stiffness; whole body vibration training; hypocaloric diet; prehypertension; arterial function; adipocytokines
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypertension; Prehypertension
• Other Study ID Numbers: HSC2011.6728

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No