Guest blogger Erin Kurdyla: I am a 31-year-old mother of four boys -- ages 5, 4, 2 1/2 and 6 months -- and yes(!!!) I'm back in my "skinny jeans." Moms out there: don't hate me.

I don't live on lettuce, I don't have a nanny, and although I wish I had a personal chef, I don't. Good genes may have a little something do to with it (thanks, mom and dad), but the real secret to my success is plain old HARD WORK. I refuse to let sleep deprivation, a crazy hectic schedule, my boys, the weather, etc. serve as an excuse to skip a workout. Instead, I fit in fitness somehow, in some way, every single day. Why? Exercise makes me feel good. And when I feel good, I'm nicer, funnier, more confident, and most importantly, a better mom.

Now let's get down to the nitty-gritty. Here are a few of my stay-fit secrets...

IMPROVISE: I tone my tush while waiting in the carpool line at nursery school. (Try it: Squeeze and release your cheeks 10 to 12 times; repeat.) I rock out around the kitchen while making dinner. You'd be surprised how random acts of fitness add up!

MAKE A DATE Wednesday night is ladies' night! My mom, aunt, cousin, sister-in-law and I have a standing "appointment" to dance our pants off at Zumba class. Knowing my workout buddies will be there makes me more accountable.

JOIN A TEAM My sister and I relive our high school glory by playing on an over-30 soccer team on Sunday mornings. (Let's go, United!) We burn serious calories without setting foot in a gym and have made great new friends in the process.

INVOLVE THE KIDS Twice a week, I teach stroller aerobics with the whole gang in tow. (Thank goodness for double strollers and scooter attachments). The boys have a blast and I don't need a babysitter. Find a class near you at: Strollerstrides.com.

THINK BIG picture, that is. At the end of the day, my no-excuses policy and all of my hard work is really about my kids. I want to be around for them, keep up with them, and hopefully watch them grow up to be healthy, happy men.

Visit Erin Kurdyla's blog at Self.com.