Q: I had a baby via c-section two months ago. What kind of exercises can I do that won't put much pressure on the area that's healing, but that will help me to get rid of some—if not all—of the belly fat? Even before I was pregnant, I seemed to store more abdominal fat in the lower part of my torso. What exercises can target that?

A: Most women who have vaginal deliveries get the go-ahead to start exercising about six weeks after birth. But if you've had a c-section or a severe episiotomy, you may need to wait longer, and you should only start once your doctor has said that it's safe for you to do so. Once you start, the key is to ease into things gently and progress gradually.

Few moms lose all their baby weight right away, and if you're breast-feeding, you're likely to carry an extra reserve to help fuel the milk-making process. Nursing moms need an extra 500 calories a day. While that seems like a lot of calories, it's easy to eat much more than that amount, thwarting your plans to slim down.

Like many moms, you seem to be in a hurry to shed the excess fat. And most people mistakenly believe that abdominal exercises are the best way to accomplish that. No research has shown that abdominal exercises can decrease belly fat. Plus, many ab moves can increase the pressure on your belly, pelvic floor and back, and if your abdominal separation—or diastasis recti—is not fully healed, some exercises can impede its healing process. The book I wrote with Lisa Druxman, M.A., the founder of StrollerStrides, provides a full nine-month postpartum exercise plan. Lean Mommy  gives lots of specifics to lose fat and firm up all over, including several exercises that target your core belly and back muscles.

An exercise for postpartum bellies

After your doctor gives you the go-ahead to exercise, try this visualization exercise called "belly lacing": Imagine that you have a ribbon woven in and around your ribcage. Close your eyes and imagine pulling on the ends of the ribbon to compress the entire area so that your ribcage narrows. Hold the tightened torso for as long as you comfortably can while you breathe normally. Then relax and repeat.

This type of core-strengthening exercise will help firm up your midsection, but none of these moves will decrease your body fat. Lots of moms (and other people, too) incorrectly believe that stomach moves can reduce inches of fat from their waistline. Since very few calories are burned during these moves, and they only strengthen the musculature, this is just not possible. The way to reduce fat in your belly—and all over—is by moving more, and that means more walking and other types of cardio (swimming, cycling, using cardio machines, etc.). How much you should do depends what you have time for, but moving for at least 30 to 60 minutes per day on most days of the week is recommended. If that seems impossible, that's what strollers are good for—getting baby outside so mom can walk!

Snooze, baby, snooze

Other areas that play a role in body fat include how much sleep you get. A lack of sleep has been linked to adult obesity, and a recent study found an association with post-pregnancy weight retention as well. A 2007 study in the American Journal of Epidemiology compared how much sleep 940 moms were getting six months after birth to the amount of excess weight they still carried one year after birth. Moms that were getting fewer than five hours of sleep per 24-hour period six months after having a baby were 2.3 times more likely to still carry at least 11 extra pounds.

This finding held even after the researchers accounted for other factors that might influence weight gain, including how much weight had been gained during pregnancy; how heavy women were before they got pregnant; how many kids they had had; and certain behaviors like dieting, food intake, exercise, and amount of TV watching. Also, women who reported getting decreasing amounts of sleep from six months postpartum to one year were two times more likely to be holding on to excess weight.

While there's no proof that sleeping more aids weight loss, research has shown plausible mechanisms for insufficient sleep to contribute to weight gain. Sleep deprivation seems to cause imbalances in hormones such as leptin, which affects energy expenditure, and ghrelin, which affects how hungry you are. Cortisol, a stress hormone, may also be altered, leading to increased hunger—and, therefore, increased caloric intake.

Of course, getting enough sleep is a luxury for many moms, especially those who work outside the home, those who are juggling a baby along with other young children, or moms who have little or no outside support. But this study suggests that it's a good idea to brainstorm for ways to sneak in more ZZZs whenever possible.