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

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

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.

Study Overview

• Status: Completed
• Conditions: Cardiovascular Diseases; Hypertension; Postmenopausal; Overweight or Obese
• Intervention / Treatment: Behavioral: Exercise

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.

• Study Type: Observational
• Enrollment (Actual): 464

Contacts and Locations

Study Locations

• United States
  • Texas
    • Dallas, Texas, United States, 75230
      • The Cooper Institute
    • Dallas, Texas, United States, 75201
      • Oak Cliff-South Dallas

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 45 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

• Sampling Method: Non-Probability Sample

Study Population

Postmenopausal women aged 45 to 75 years who are overweight

Description

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.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
VO2max and resting systolic blood pressure	at 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fasting blood lipids and lipoproteins (total, HDL-, and LDL-cholesterol, triglycerides		at 6 months
High sensitive C-reactive protein		at 6 months
Fasting glucose		at 6 months
Anthropometry (body composition and regional fat distribution)		at 6 months
Blood pressure response to exercise		at 6 months
Heart rate variability		at 6 months
Health-related quality of life and other psychosocial variables		at 6 months
Cardiovascular disease risk determined by a multiple logistic risk function		at 6 months
Tertiary Outcomes	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.	at 6 months

Collaborators and Investigators

• Sponsor: Pennington Biomedical Research Center
• Collaborators: National Heart, Lung, and Blood Institute (NHLBI)
• 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

Publications and helpful links

General Publications

• Morss GM, Jordan AN, Skinner JS, Dunn AL, Church TS, Earnest CP, Kampert JB, Jurca R, Blair SN. Dose Response to Exercise in Women aged 45-75 yr (DREW): design and rationale. Med Sci Sports Exerc. 2004 Feb;36(2):336-44. doi: 10.1249/01.MSS.0000113738.06267.E5.
• Jurca R, Church TS, Morss GM, Jordan AN, Earnest CP. Eight weeks of moderate-intensity exercise training increases heart rate variability in sedentary postmenopausal women. Am Heart J. 2004 May;147(5):e21. doi: 10.1016/j.ahj.2003.10.024.
• Jordan AN, Jurca GM, Locke CT, Church TS, Blair SN. Pedometer indices for weekly physical activity recommendations in postmenopausal women. Med Sci Sports Exerc. 2005 Sep;37(9):1627-32. doi: 10.1249/01.mss.0000177455.58960.aa.
• Kline CE, Sui X, Hall MH, Youngstedt SD, Blair SN, Earnest CP, Church TS. Dose-response effects of exercise training on the subjective sleep quality of postmenopausal women: exploratory analyses of a randomised controlled trial. BMJ Open. 2012 Jul 12;2(4):e001044. doi: 10.1136/bmjopen-2012-001044. Print 2012.
• Johannsen NM, Swift DL, Johnson WD, Dixit VD, Earnest CP, Blair SN, Church TS. Effect of different doses of aerobic exercise on total white blood cell (WBC) and WBC subfraction number in postmenopausal women: results from DREW. PLoS One. 2012;7(2):e31319. doi: 10.1371/journal.pone.0031319. Epub 2012 Feb 17.
• Stewart LK, Earnest CP, Blair SN, Church TS. Effects of different doses of physical activity on C-reactive protein among women. Med Sci Sports Exerc. 2010 Apr;42(4):701-7. doi: 10.1249/MSS.0b013e3181c03a2b.
• Church TS, Martin CK, Thompson AM, Earnest CP, Mikus CR, Blair SN. Changes in weight, waist circumference and compensatory responses with different doses of exercise among sedentary, overweight postmenopausal women. PLoS One. 2009;4(2):e4515. doi: 10.1371/journal.pone.0004515. Epub 2009 Feb 18.
• Martin CK, Church TS, Thompson AM, Earnest CP, Blair SN. Exercise dose and quality of life: a randomized controlled trial. Arch Intern Med. 2009 Feb 9;169(3):269-78. doi: 10.1001/archinternmed.2008.545.
• Earnest CP, Lavie CJ, Blair SN, Church TS. Heart rate variability characteristics in sedentary postmenopausal women following six months of exercise training: the DREW study. PLoS One. 2008 Jun 4;3(6):e2288. doi: 10.1371/journal.pone.0002288.
• Church TS, Earnest CP, Skinner JS, Blair SN. Effects of different doses of physical activity on cardiorespiratory fitness among sedentary, overweight or obese postmenopausal women with elevated blood pressure: a randomized controlled trial. JAMA. 2007 May 16;297(19):2081-91. doi: 10.1001/jama.297.19.2081.

Study record dates

Study Major Dates

• Study Start: January 1, 2001
• Primary Completion (Actual): December 1, 2006
• Study Completion (Actual): December 1, 2006

Study Registration Dates

• First Submitted: February 13, 2001
• First Submitted That Met QC Criteria: February 12, 2001
• First Posted (Estimate): February 13, 2001

Study Record Updates

• Last Update Posted (Actual): September 15, 2022
• Last Update Submitted That Met QC Criteria: September 13, 2022
• Last Verified: September 1, 2022

More Information

Terms related to this study

• Keywords: Cardiovascular Diseases; Hypertension; Women; Sedentary; Postmenopausal; Overweight or Obese
• Additional Relevant MeSH Terms: Vascular Diseases; Body Weight; Hypertension; Cardiovascular Diseases; Overweight
• Other Study ID Numbers: PBRC 26043; R01HL066262 (U.S. NIH Grant/Contract)