Effects of a partially home-based exercise program for women with gestational diabetes. Effect of exercise on blood pressure in pregnant women with a high risk of gestational hypertensive disorders.
To examine the effectiveness of a partially home-based, moderate-intensity aerobic exercise program for women with gestational diabetes.
                This was a randomized experimental design. Thirty-three women with gestational diabetes were randomly assigned to the exercise or the no-exercise group. Subjects underwent hemoglobin A1C assay and submaximal cycle ergometer fitness tests at baseline and at study conclusion. Subjects kept diaries of home fasting and 2-hour postprandial blood glucose determinations. Exercise subjects were asked to exercise for 30 minutes three to four times weekly at 70% of estimated maximal heart rate for the weeks of study participation. Two exercise sessions weekly were supervised by the investigator, and two were unsupervised at home. Control-group subjects were asked to maintain their current activity level.
                Daily fasting and postprandial blood glucose levels, hemoglobin A1C, incidence of exogenous insulin therapy, and incidence of newborn hypoglycemia were not different between the groups. There was a training effect in the exercise group (P = .005) but not in the control group (P = .25). A significant decline in daily grams of carbohydrate consumed was observed in the control group (P = .03), but not in the exercise group (P = .97). No complications were found in the subjects who exercised.
                A partially home-based exercise program did not reduce blood glucose levels, but did result in a modest increase in cardiorespiratory fitness. The intervention appeared safe. To prospectively determine whether moderate exercise during pregnancy lowers blood pressure.
                A randomized, controlled trial with one test group and one control group. All subjects have a history of mild hypertension, gestational hypertensive disorders or a family history of hypertensive disorders. Subjects were recruited before 14 weeks' gestation. After four weeks of observation, the subjects were randomly assigned to either the exercise or control group. The exercise group visited the laboratory three times a week for 10 weeks (18-28 gestation weeks) to perform 30 minutes of exercise at Rating of Perceived Exertion level 13.
                A total of 16 pregnant women (mean age, 30 years) participated. The mean metabolic equivalent during exercise sessions was 4.7 (SD = 0.8). Blood pressure measurements were compared before and after the 10-week exercise period in the two groups. Systolic blood pressures did not change significantly, but diastolic blood pressure (DBP) in the exercise group decreased by 3.5 mm Hg, while that in the control group increased by 1.1 mm Hg. Thus, the pre-post change in DBP differed by 4.6 mm Hg between groups. Exercise treatment reduced the diastolic blood pressure to a near-significant level in the exercise group (t = 2.34, df = 7, P = .052). Percent body fat did not differ between the exercise and control groups either before or after exercise treatment. ANOVA revealed that pregnancy had a significant effect (F(1, 14) = 5.7, P = .03) on increasing the percentage of fat, but exercise treatment did not (F(1, 14) = .18, P = .68). Estimated energy expenditure in overall daily physical activities during the intervention did not differ between the two groups despite the inclusion of exercise.
                This study detected a strong trend that 10 weeks of moderate exercise lowered the diastolic blood pressure among pregnant women at risk of hypertensive disorders. The reductions were probably due to the effect of exercise itself, not to weight or overall daily physical activity levels.
There is insufficient evidence for reliable conclusions about the effects of exercise on prevention of pre-eclampsia and its complications.
[Note: The four citations in the awaiting classification section of the review may alter the conclusions of the review once assessed.]