title: Aerobic exercise and submaximal functional capacity in overweight pregnant women: a randomized trial.
abstract: OBJECTIVE
  To evaluate the effects of aerobic training on submaximal cardiorespiratory capacity in overweight pregnant women.
  
  
  METHODS
  We conducted a randomized clinical trial in a referral center prenatal clinic during the period 2000-2002. Of 132 overweight (body mass index 26-31 kg/m2) but otherwise healthy volunteers, at 20 years of age or older, with gestational age of 20 weeks or less, and without diabetes or hypertension, 92 consented to participate and were randomized. Intervention consisted of 3 one-hour aerobic exercise sessions per week; the control group received weekly relaxation and focus group discussions. The main outcome measure was submaximal exercise capacity evaluated by oxygen uptake at the anaerobic (first ventilatory) threshold during cardiopulmonary treadmill testing 12 weeks after randomization.
  
  
  RESULTS
  Oxygen uptake at the anaerobic threshold increased 18% (15.9 +/- 2.6 to 18.1 +/- 3.1 mL . min(-1) . kg(-1)) in the exercise group but decreased 16% (16.9 +/- 3.0 to 15.8 +/- 2.6 mL . min(-1) . kg(-1)) among the control group. Oxygen consumption at the anaerobic threshold, adjusted through analysis of covariance for baseline oxygen uptake, was 2.68 (95% confidence interval 1.23 to 4.12) mL . min(-1) . kg(-1) greater in the exercise group. Women in the exercise group were approximately 5 times more likely than those in the control group to have regular or good cardiorespiratory capacity (12/38 versus 2/38; relative risk 5.2, 95% confidence interval 1.2 to 22.0, number needed to treat 5).
  
  
  CONCLUSIONS
  Aerobic training in overweight pregnant women substantially increases submaximal exercise capacity, overcoming the otherwise negative effects of pregnancy in this regard. Additional studies are required to evaluate its effect on major clinical outcomes.
authors.affiliation: Postgraduate Studies Program in Epidemiology, School of Medicine, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil. cemitta@uol.com.br
authors.forename: Iracema Athayde
authors.initials: IA
authors.lastname: Santos
authors.forename: Ricardo
authors.initials: R
authors.lastname: Stein
authors.forename: Sandra Costa
authors.initials: SC
authors.lastname: Fuchs
authors.forename: Bruce Bartholow
authors.initials: BB
authors.lastname: Duncan
authors.forename: Jorge Pinto
authors.initials: JP
authors.lastname: Ribeiro
authors.forename: Locimara Ramos
authors.initials: LR
authors.lastname: Kroeff
authors.forename: Mariana Teixeira
authors.initials: MT
authors.lastname: Carballo
authors.forename: Maria Inês
authors.initials: MI
authors.lastname: Schmidt
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold; D015444:Exercise; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D006801:Humans; D009765:Obesity / Q000503:physiopathology* / Q000628:therapy*; D010101:Oxygen Consumption / Q000502:physiology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology* / Q000628:therapy*