Dose-Response to Exercise in Women Aged 45-75 Years (DREW)

This study has been completed.
Sponsor:
Collaborator:
Information provided by (Responsible Party):
Timothy Church, Pennington Biomedical Research Center
ClinicalTrials.gov Identifier:
NCT00011193
First received: February 13, 2001
Last updated: May 25, 2012
Last verified: May 2012
  Purpose

To investigate the effects of different amounts of exercise on both cardiorespiratory fitness and risk factors for cardiovascular disease in sedentary, overweight, mildly hypertensive, but healthy, postmenopausal women aged 45 to 75 years.


Condition Intervention
Cardiovascular Diseases
Hypertension
Postmenopausal
Overweight or Obese
Behavioral: Exercise

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Dose-response to Exercise in Women Aged 45-75 Years (DREW)

Resource links provided by NLM:


Further study details as provided by Pennington Biomedical Research Center:

Primary Outcome Measures:
  • VO2max and resting systolic blood pressure [ Time Frame: at 6 months ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Fasting blood lipids and lipoproteins (total, HDL-, and LDL-cholesterol, triglycerides [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
  • High sensitive C-reactive protein [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
  • Fasting glucose [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
  • Anthropometry (body composition and regional fat distribution) [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
  • Blood pressure response to exercise [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
  • Heart rate variability [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
  • Health-related quality of life and other psychosocial variables [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
  • Cardiovascular disease risk determined by a multiple logistic risk function [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
  • Tertiary Outcomes [ Time Frame: at 6 months ] [ Designated as safety issue: No ]
    Other variables of interest include dietary habits, physical activity history, smoking, alcohol intake, sleep habits, medication use (including HRT), demographic characteristics, unstructured physical activity, menstrual history, and personal and family medical history.


Biospecimen Retention:   Samples With DNA

whole blood


Enrollment: 464
Study Start Date: January 2001
Study Completion Date: December 2006
Primary Completion Date: December 2006 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Non-Exercise Control Group
We randomly assigned 102 women in the non-exercise control group and were asked to maintain their level of activity for the 6-month study period.
Behavioral: Exercise
Compared the effect of 50%, 100%, and 150% of the NIH Consensus Development Panel recommended physical activity dose on fitness in women.
4-kcal/kg Energy Expenditure per week
We randomly assigned 155 women to the 4-kcal/kg per week group for 6 months.
Behavioral: Exercise
Compared the effect of 50%, 100%, and 150% of the NIH Consensus Development Panel recommended physical activity dose on fitness in women.
8-kcal/kg Energy Expenditure per week
We randomly assigned 104 women to the 8-kcal/kg per week group for 6 months.
Behavioral: Exercise
Compared the effect of 50%, 100%, and 150% of the NIH Consensus Development Panel recommended physical activity dose on fitness in women.
12-kcal/kg Energy Expenditure per week
We randomly assigned 103 women to the 12-kcal/kg per week group for 6 months.
Behavioral: Exercise
Compared the effect of 50%, 100%, and 150% of the NIH Consensus Development Panel recommended physical activity dose on fitness in women.

Detailed Description:

BACKGROUND:

The primary goal of the Dose-Response to Exercise in Women aged 45-75 Years (DREW) was to investigate the effects of different amounts of exercise on both cardiorespiratory fitness and risk factors for cardiovascular disease. Participants were sedentary, overweight or obese, postmenopausal women who had high normal blood pressure or Stage I hypertension, and thus are at moderately high risk for cardiovascular disease. A total of 464 women (about 35% were recruited from minority groups) were randomly assigned to a control group (N = 102) or to 1 of 3 exercise groups (N = 155 for the lowest exercise dose and 104 in the 8-kcal/kg group and 103 in the 12-kcal/kg exercise group). Women assigned to the exercise groups exercised for 6 months at energy expenditures of 4, 8, or 12 kcal ·kg-1 · week-1. These exercise doses represent the consensus public health recommendation for physical activity from recently published guidelines from the U.S. Public Health Service, American Heart Association, and American College of Sports Medicine (8 kcal ·kg-1 · week-1) and at doses 50% below (4 kcal ·kg-1 · week-1) and 50% above (12 kcal ·kg-1 · week-1) the consensus dose. All women exercised at 50% of V02 max. The exercise sessions took place in the exercise laboratory, with individual supervision of each session and strict control of frequency, duration, and intensity. This was provided thorough documentation of the exact amount of exercise completed. Primary outcome measures are VO2 max and resting systolic blood pressure. Other cardiovascular disease risk factors, psychosocial variables, health-related quality of life, body composition, and fat distribution are secondary outcomes. Other secondary analyses included a focus on the extent to which observed dose-response effects are modified by baseline levels of fitness, ethnicity, risk factors, or age. Assessments will take place at baseline and 6 months. The research provided information about (1) patterns of change in outcomes produced by each of several exercise doses, (2) whether performing exercise at less than the current consensus dose has any benefit, (3) whether performing more exercise than the consensus dose has greater (or proportionally greater) health benefits, and (4) the characteristics of sedentary women who are most likely to benefit from various exercise doses.

DESIGN NARRATIVE:

A total of 464 sedentary, postmenopausal women at moderate risk for cardiovascular disease was randomly assigned to receive exercise training at one of three doses (4, 8, or 12 kcal/kg/wk) or no exercise for six months duration. The specific aims were be to determine: (a) if women in the exercise groups have increased aerobic power (VO2max) over the six months compared to the no exercise group; (b) if women in the exercise groups have a greater reduction in resting systolic blood pressure than those in the no exercise group; and, (c) if there will be a dose-response gradient across the three exercise groups for changes in aerobic power and systolic blood pressure. Secondary aims include evaluating the effects of exercise dose on fasting blood lipids and lipoproteins, glucose, insulin, anthropometry, self-reported quality of life, and cardiovascular risk as determined by a multiple logistic risk function. Covariates to be controlled included dietary intake, physical activity (outside of the exercise program), smoking, alcohol intake, sleep habits, medication use (including hormone replacement therapy), demographics, menstrual history, personal and family medical history.

  Eligibility

Ages Eligible for Study:   45 Years to 75 Years
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Postmenopausal women aged 45 to 75 years who are overweight

Criteria

Postmenopausal women aged 45 to 75 years who are overweight or obese (body mass index of 25 to 40 kg/m2) and have normal or mildly elevated BP.

  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00011193

Locations
United States, Texas
The Cooper Institute
Dallas, Texas, United States, 75230
Oak Cliff-South Dallas
Dallas, Texas, United States, 75201
Sponsors and Collaborators
Pennington Biomedical Research Center
Investigators
Principal Investigator: Steven N. Blair, PED University of South Carolina
Principal Investigator: Timothy S. Church, MD, PhD, MPH Pennnington Biomedical Research Center
Study Director: Conrad P. Earnest, PhD University of Bath
Study Director: James S. Skinner, hD Indiana University
  More Information

Publications:
Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Timothy Church, Principal Investigator, Pennington Biomedical Research Center
ClinicalTrials.gov Identifier: NCT00011193     History of Changes
Other Study ID Numbers: HL66262, R01HL066262
Study First Received: February 13, 2001
Last Updated: May 25, 2012
Health Authority: United States: Federal Government

Keywords provided by Pennington Biomedical Research Center:
Cardiovascular Diseases
Hypertension
Postmenopausal
Overweight or Obese
Women
Sedentary

Additional relevant MeSH terms:
Cardiovascular Diseases
Hypertension
Overweight
Vascular Diseases
Body Weight
Signs and Symptoms

ClinicalTrials.gov processed this record on April 16, 2014