I know nine expecting mothers right now. NINE. About half of them are running friends and/or buddies. Exercise and pregnancy, and running during pregnancy, are hot topics. How much is too much? How fast is too fast? How far is too far?

Exercise is very beneficial for pregnant women. I should know. Because I did the opposite. I didn’t do any exercise when I was pregnant, and I should have. I walked…every once in a while, but not consistently. Being inactive and sedentary (accompanied with indulging in too many ice cream sundaes) contributed to post-pregnancy back problems (and non-baby-related weight gain!).

An article “Exercise During Pregnancy,” on WebMD states that regular exercise during your pregnancy can help to improve posture, can reduce pain from backaches and even help you feel less fatigued. In fact, if you were working out before you were pregnant, you can continue in moderation. “Don’t try to exercise at your former level; instead, do what’s most comfortable for you now,” the article states. “Low impact aerobics are encouraged versus high impact,” for example.

If you weren’t exercising regularly, however, adding a strenous activity after you’ve become pregnant, is not advised. Walking regularly is, though.

The WebMD article also states that most exercises are safe. The safest? Swimming, brisk walking, indoor stationary cycling, a step machine or an elliptical machine, and low-impact aerobics. Click the link to see the exercises and activities not considered safe during pregnancy.

Most of the runners I know who are pregnant are continuing to run and exercise during their pregnancy, which goes right along with the advice of doctors, including Dr. Lanalee Sam, MD, medical director for Elite Obstetrical and Gynecology in Fort Lauderdale, Fla. In the article “Running for Two: Guidelines for Pregnant Runners,” featured on BabyZone.com, Dr. Sam says that a healthy, low-risk pregnancy allows women to continue their exercise routines without dramatic changes.

In the BabyZone.com article, New York-based Dr. Annette Perez-Delboy, MD, says there are things to watch out for when running while pregnant, such as a very fast heartbeat, shortness of breath and any bleeding. If you feel any of those symptoms, stop immediately. Dr. Sam adds that dizziness, fatigue, abdomen tightening (contractions) or any fluid leakage are all also signs you should stop.

Of course, you should always talk to your own doctor before exercising during pregnancy–just in case.

Did you run during your pregnancy? What were the pros? The cons? Let us (and other expectant moms) know in the comments below!