Low-intensity Resistance Exercise and Diet on Arterial Function and Blood Pressure

Effects of Low-intensity Resistance Exercise Training and Diet on Central Hemodynamics and Arterial Stiffness in Obese Middle-aged Women With High Blood Pressure

• 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. Low-intensity resistance exercise training (LIRET) results in similar increases in muscle mass and strength than those observed after high-intensity resistance exercise.
• The investigators hypothesis is that weight loss via diet combined with LIRET would additively reduce arterial stiffness and blood pressure (BP) 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: Resistance exercise training; Other: Resistance exercise training & diet

Detailed Description

The purpose of the study is to examine the effects of 12 weeks of low-intensity resistance exercise training (LIRET) and diet on arterial function, autonomic function, and body composition in obese women with high blood pressure (BP). Specific aims of the study are to:

• To evaluate the extent to which diet and LIRET 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 LIRET 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). Circulating levels of adipocytokines (adiponectin and leptin) and endothelial-derived vasodilators (NO metabolites [NOx] and prostacyclin) and vasoconstrictors (endothelin-1 and prostaglandin F2α) will be assessed as secondary outcome variables.

• Study Type: Interventional
• Enrollment (Actual): 41
• 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: 40 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Female
• 40 to 65 years of age
• Body mass index of 27-39.9
• Sedentary or low active (less than 2 hr per wk)

Exclusion Criteria:

• Younger than 40 or older than 65 years of age
• Body mass index lower than 27, or 40 or higher
• Physically active or competitively active
• Smoker
• Systolic blood pressure higher than 140 mmHg
• Use of hormone replacement therapy of less than 1 yr
• Use of calcium channel blocker or beta blockers
• Type 1 diabetes
• Uncontrolled type 2 diabetes

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

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: Resistance exercise training; Lower-body exercises 3 times per wk for 12 wk	Other: Resistance exercise training; The low intensity resistance exercise training intervention consists of lower-body resistance exercise (machines) 3 times per wk for 12 wk. Two sets the first 2 wk and 3 sets the rest of the intervention, at 40% of the estimated 1 repetition maximum, for 17 to 23 repetitions, with 1 minute of rest in between sets.
Experimental: Resistance exercise training & diet; Lower-body exercise training and diet	Other: Resistance exercise training & diet; Combination of low intensity resistance exercise training and hypocaloric diet

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood pressure	Non-invasive measures of brachial and aortic blood pressure	12 weeks

Secondary 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
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
Endothelial Function	By measuring circulating levels of adipocytokines (adiponectin and leptin) and endothelial-derived vasodilators (NO metabolites [NOx] and prostacyclin) and vasoconstrictors (endothelin-1 and prostaglandin F2α)	12 weeks

Collaborators and Investigators

• Sponsor: Florida State University
• Collaborators: Nutrisystem, Inc.
• Investigators: Principal Investigator: Arturo Figueroa, M.D., Ph.D., Florida State University

Publications and helpful links

General Publications

• Figueroa A, Vicil F, Sanchez-Gonzalez MA, Wong A, Ormsbee MJ, Hooshmand S, Daggy B. Effects of diet and/or low-intensity resistance exercise training on arterial stiffness, adiposity, and lean mass in obese postmenopausal women. Am J Hypertens. 2013 Mar;26(3):416-23. doi: 10.1093/ajh/hps050. Epub 2013 Jan 7.

Study record dates

Study Major Dates

• Study Start: December 1, 2010
• Primary Completion (Actual): December 1, 2011
• Study Completion (Actual): June 1, 2012

Study Registration Dates

• First Submitted: June 9, 2011
• First Submitted That Met QC Criteria: June 9, 2011
• First Posted (Estimate): June 10, 2011

Study Record Updates

• Last Update Posted (Estimate): August 5, 2014
• Last Update Submitted That Met QC Criteria: August 4, 2014
• Last Verified: August 1, 2014

More Information

Terms related to this study

• Keywords: obesity; hypertension; autonomic function; pulse wave velocity; endothelial function; arterial stiffness; hypocaloric diet; prehypertension; arterial function; adipocytokines; low intensity resistance exercise training
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypertension; Prehypertension
• Other Study ID Numbers: 2011.5485