Aerobic exercise and submaximal functional capacity in overweight pregnant women: a randomized trial.
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.
Santos
Iracema Athayde
IA
Postgraduate Studies Program in Epidemiology, School of Medicine, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil. cemitta@uol.com.br
Stein
Ricardo
R
Fuchs
Sandra Costa
SC
Duncan
Bruce Bartholow
BB
Ribeiro
Jorge Pinto
JP
Kroeff
Locimara Ramos
LR
Carballo
Mariana Teixeira
MT
Schmidt
Maria Inês
MI
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*