Parenthood puts a damper on workouts

ATLANTA, Georgia (CNN) -- They might be the apple of your eye, but chances are, they're the reason the apple pie is sticking to your thighs! That's right, our kids are making us fatter. Well, actually, less fit. Researchers at the University of Pittsburgh studied 525 adults and found that although marriage has almost no effect on how much time men or women exercised, having children does.

New moms lost about a third of their pre-pregnancy workout time; new dads lost about half. Men worked out about two hours more per week than women did before becoming parents, so in the end it all pretty much evened out. Male or female, having kids equals less working out.

But what's the reason for this fitness phaseout? According to Dr. Andrea Sharma, an epidemiologist at the U.S. Centers for Disease Control and Prevention, the answers won't surprise anyone. The usual suspects are at work: "The barriers [new parents] usually cite are fatigue, limited time and [lack] of social support."

Sharma, whose work at the CDC includes identifying and breaking down barriers that prevent us from getting enough physical activity in our daily lives, says the biggest exercise obstacle that new parents face is time. But it's not what you might be thinking.

It's not just the actual tick-tock thing; it's also our own perception of time. That perception is especially prevalent in an "all or nothing" standoff many of us have with that magic number, 30: 30 minutes of exercise, that is.

"The recommendations for adults is to take in 30 minutes of moderate-intensity physical activity most days of the week," Sharma said. "And I think the most important thing for parents to realize is that you don't have to engage in that all at the same time. You can break it out through out the day in 10- to 15-minute intervals." Watch new moms exercise with babes in arms »

So instead of just throwing up your hands and saying "Fuggedaboutit" if you can't hop on the treadmill for a half an hour or do an entire Pilates class, instead grab 10 minutes here or there just three times a day, and you'll hit that physical activity mark.

The University of Pittsburgh study looked only at new parents, so things might ease up as the children grow. But Sharma encourages young moms and dads to look for ways to incorporate fitness into their families' lives whenever they can.

"Make time in life to exercise by cutting back on other things, like television time or computer time, or even use the time when you're taking your kids to their activities, time where you might just be sitting and waiting, to get active," she said. "Go for a run or a walk."

And should you feel guilty about taking time away from your young child by working out, you might want to keep a few things in mind. First, being a healthy role model for your children is probably the best way to show them how to get and keep exercise in their lives. Also, working out will increase new parents' stamina, which will come in handy for those many hours of sleep you end up missing when the kids are young,

It'll be even more important as those young toddlers grow into teenagers and you end up losing sleep for a whole lot of different reasons. E-mail to a friend

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