Kettlebell instructor Jessica Huthmaker, center, leads a class at Kettlebell Konnection, in Colorado Springs, Colorado. Huthmaker is in her seventh month of pregnancy.

COLORADO SPRINGS, Colo. — Pregnancy and pumping iron don't typically go together, but Jessica Huthmaker wants to change that.

Seven months pregnant with her first child, the owner of Kettlebell Konnection hasn't slowed down yet.

"The only thing I've changed is I've gone a little lighter, and I make sure my heart rate doesn't go above 140," Huthmaker said. "I've kind of used myself as an experiment and I really feel great physically. So far, pregnancy has been a breeze."

At a recent group class with a handful of women, she was easily swinging the heavy kettlebells past her burgeoning belly.

A longtime weightlifter and kettlebell aficionado, Huthmaker began her business in Colorado Springs about a year ago, as kettlebells were gaining popularity among celebrities and fashion-forward gyms.

Since that time, the Kettlebell Konnection studio has developed a strong female power atmosphere. And as Huthmaker moves into the motherhood 'hood,' it's also become an incubator for mommy power.

The five women gathered at the recent group session all happened to be mothers. And new mom Amanda Hawkins brought 2-month-old Jack, who watched calmly from his car seat as the ladies worked out. She started using kettlebells six weeks after Jack was born, to firm up after her pregnancy.

The women are a sorority, offering support or clapping after a friend completes a hard set. They chatted with first-time mom Huthmaker about Braxton Hicks contractions while they were all on the floor doing a move called a Russian twist.

And when little Jack began to fuss, Mom handed him off to Huthmaker, who fed him a bottle while she instructed her pupils.

The women want to look good and feel good and be ready for the tasks of motherhood.

"As a mom, you spend all day lifting odd-shaped objects — kids, groceries," said fellow kettlebell trainer Autum Romano. "That's exactly what kettlebell training is."

Strength training for moms is one thing, but Huthmaker is confronting an old taboo by doing strength training during pregnancy. Won't she hurt the baby?

Her midwife, Dotti Kirkpatrick, said that while every woman should consult her own doctor or midwife, the conventional wisdom has shifted for healthy, low-risk pregnant women. Strength training is fine, with a few caveats: Listen to your body, don't start anything new during pregnancy, and don't exceed a temperature of 100 degrees or heart rate of 140 during exercise.

"If you're already accustomed and used to putting your body through those things, you don't have to stop," said Kirkpatrick, who has delivered about 300 babies during the past 10 years. "We do have them cut back a little (on weight). Because of some of the hormones in pregnancy, they can injure their ligaments."

Hormones during pregnancy make ligaments more pliable for the birthing process. Which means having a hard body could have its drawbacks, too, if well-toned core muscles slow down the birth. Kirkpatrick said she hasn't seen studies correlating birth-process duration to high levels of fitness, and every birth is different. But anecdotally, she's noticed that some of her most fit patients have had very long births.

So, Huthmaker's experiment with her own fitness during pregnancy is far from over.