Maternal hemodynamic responses to two different types of moderate physical exercise during pregnancy: a randomized clinical trial

Background/Aim:  Maternal hemodynamic responses (heart rate, systolic and diastolic blood pressure) were compared during two types of moderate-intensity physical exercise. Methods:  A randomized clinical trial compared 120 pregnant women performing physical exercise on a treadmill (n=64) or stationary bicycle (n=56).  In 44 of these women (n=23 treadmill; n=21 bicycle), blood pressure was monitored for 24 hours following exercise.  Repeated-measures analysis compared maternal heart rate, systolic and diastolic blood pressure before, during and in the 24 hours following exercise in both groups.  Results:  Maternal heart rate increased significantly (p<0.001) with both types of exercise (from 84 at rest to 112 bpm on the treadmill and from 87 at rest to 107 bpm on the bicycle), without exceeding the limit of 140 bpm.  Systolic pressure increased from 110 at rest to 118 mmHg on the bicycle (p=0.06) and from 112 at rest to 120 mmHg on the treadmill (p=0.02).  Systolic pressure dropped steadily following exercise, reaching its lowest level (104 mmHg) after 14 hours, increasing thereafter and returning to pre-exercise levels by the 19th hour.  Diastolic pressure increased during exercise irrespective of the type of exercise (p=0.27), from 70 at rest to 75 mmHg on the bicycle (p=0.39) and from 70 at rest to 76 mmHg on the treadmill (p=0.18), with the lowest level (59 mmHg) being at the 13th hour. Conclusions:  A slight increase in blood pressure levels was found during exercise; however, this was not clinically significant and was followed by a substantial hypotensive effect that lasted around 19 hours. Register: Clinical Trials NCT01383889.