Though the abdominals do not tend to look toned during pregnancy, they can still stay strong. In fact, it is often advised that they be worked out in some way over the nine months of pregnancy, though it is a good idea for women to mention her intentions to their doctor first. One of the safest pregnancy ab exercises is a modified version of the crunch, using either pillows or an exercise ball to support the back. The reverse crunch is usually a good ab exercise during pregnancy, as well. Pelvic tilts are another ab exercise that is usually considered gentle enough for pregnant women to safely perform.
It may be difficult to complete a regular crunch while pregnant, but it is possible to get the benefits of this exercise through a modified version. The woman should start by either lying on an exercise ball, or leaning her back against a stack of pillows so that she is not lying flat on her back. Once the woman is leaning back with knees bent and hands behind her head, she should contract the abdominals while lifting the head and torso forward. Once she has lifted the torso as far forward as possible, she should hold the position for one second, and then return to the starting point. It is advised that she perform these pregnancy ab exercises about 20 times per workout session, though she should stop if the movement becomes uncomfortable.
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Another alternative to the typical crunch is the reverse crunch. Like many pregnancy ab exercises, it requires the woman to start out leaning against a soft surface to support the back, such as a pile of pillows. She should lean back into the pillows, with the palms on the floor and legs bent. The next step is to contract the abdominals in order to tilt the pelvis forward, using the arms for help if necessary. She should hold for one second before releasing and starting over, with the goal being about 20 repetitions.
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One of the gentlest pregnancy ab exercises is the pelvic tilt. The pregnant woman is advised to start by lying on her back with legs bent, feet flat on the ground. The next step is to lift the pelvis up as far as possible, while still keeping the upper body on the ground. The woman should then slowly return the pelvis to the ground, repeating the move about 45 times in a workout session. It should be noted that after 16 weeks of pregnancy, women should avoid performing pregnancy ab exercises that require them to lie flat on their back, since this can cut off oxygen to the uterus, which means that the other exercises would be best after first trimester; a woman should never hesitate to consult her obstetrician if she has any doubts.