title: A randomized comparative trial of the efficacy and safety of exercise during pregnancy: design and methods.
abstract: Use of an exercise intervention for high-risk and vulnerable populations, such as pregnant women at risk for gestational hypertension or preeclampsia, requires special consideration. A comparative trial testing the effects of two types of physical exercises - stretching (a comparator) and walking (a testing intervention) - for sedentary pregnant women at risk for preeclampsia - is presented in this paper. The study was designed to reduce post-randomization bias and dropout rates from both groups, and closely to monitor safety of subjects. The strengths of the study design and methods include use of a run-in phase; use of a stretching exercise as a comparator; multiple ways to measure daily physical activities and the exercise intervention; and tailored support to remove barriers to exercise for subjects. The intervention consists of 40 min of walking at moderate intensity (i.e., 55-69% of maximum heart rate and rating of perceived exhaustion 12-13) five times a week from 18 weeks gestation until birth. The comparator exercise consists of 40 min of stretching exercise without increasing heart rate to more than 10% of resting heart rate, five times a week from 18 weeks gestation until birth. The primary outcome is the incidence of preeclampsia. Secondary outcomes include the physiologic effects of the intervention and birth outcomes.
authors.affiliation: University of Michigan School of Nursing, Division of Health Promotion and Risk Reduction, 400 North Ingalls, Ann Arbor, Michigan 48109, United States. seonaeyo@umich.edu
authors.forename: SeonAe
authors.initials: S
authors.lastname: Yeo
mesh_terms: D000328:Adult; D016640:Diabetes, Gestational / Q000628:therapy*; D015444:Exercise; D005260:Female; D006801:Humans; D046110:Hypertension, Pregnancy-Induced / Q000628:therapy*; D052580:Muscle Stretching Exercises; D011225:Pre-Eclampsia / Q000628:therapy*; D011247:Pregnancy; D012107:Research Design; D016896:Treatment Outcome; D016138:Walking