During pregnancy, your body undergoes massive changes, both physical and hormonal, not to mention emotional changes. Pregnancy can cause your cartilage to become softer and loser, in preparation for the flexibility in your hips during birth.
Walking is an excellent exercise during pregnancy, and is especially good for women who can push other children in a stroller for their daily fresh air.
Swimming is not only fun but a great way to get in shape. It eases tension on your body from the extra weight you carry and you can exericse without places pressure on your feet. Just remember to skip the sauna and the hot tub which can raise your body temperature above what is considered safe for the baby.
Special pregnancy exercise classes are popping up in cities and towns everywhere. These exercise classes are specifically designed for pregnanct women, and are most often taught by a regular fitness instructor who happens to be pregnant at the time, or who has recently given birth. Some places even offer postpartum classes, where you can keep your baby in the carrier on the sidelines, or even wear a baby carrier. This is the only adult exercise class you will find where babies are allowed.
Always remember to consult your physician prior to beginning any new exercise program so she can make any recommendations based upon your pregnancy. Because each pregnancy is different, you might even have different recommendations from one pregnancy to the next.