Photo by Zachary Siebert / St. Joseph News-Press / Purchase this photo

Fitness enthusiasts Kaitlin Ericson, left, and Danielle Venable do sit-ups at Body Image Gym Wednesday, October 22nd. The two have engaged in serious competiton of feats of strength recently, even doing as many as 1500 sit-ups straight.

Training athletes is nothing new to Bob Boyles.

The certified strength and conditioning specialist, who owns Body Image Personal Training at 5521 Claremont St., for years was the strength and conditioning coach at Missouri Western State University. But even with all this experience, it wasn’t until a few weeks ago he witnessed someone do 1,500 sit-ups straight.

This someone isn’t a star athlete you’ll see on the football field or basketball court. Rather, she is Kaitlin Ericson, a soon-to-be freshman at Missouri Western — and she isn’t alone in her ability to demonstrate an unusual amount of endurance. Danielle Venable, another of Mr. Boyles’ clients, has totaled 1,082 sit-ups in a competition she and Ms. Ericson began several months ago and that has also come to include “events” such as hanging abdominal exercises and squats.

“It makes me tired just watching them,” Mr. Boyles says. “What they represent is willpower, and (acquiring this) is the struggle people face in sticking with a workout program. It’s easy to be a slacker when you’re not around people who aren’t.”

Although the women train on different days of the week and therefore don’t usually compete side by side, knowing they have each other’s records to keep pace with has been a big motivator — especially when in the middle of sit-up sessions that can last close to an hour and a half.

“It makes training more fun for us,” says Ms. Venable, who, when she’s not at the gym, works as a chemist and takes care of her daughter.

And although she trails behind Ms. Ericson in sit-ups, the two are tied at 45 for the squats they do while holding 35-pound weights and are also neck-in-neck in hanging leg-raise pull-ups: As of Wednesday, Ms. Venable’s record was 100, and Ms. Ericson’s record was 125.

For both, these feats of endurance have come after years of training with Mr. Boyles; Ms. Ericson began coming to him four years ago after sitting in on some of her boyfriend’s sessions, and Ms. Venable began coming eight years ago, when she was competing in the Miss Missouri pageant. Their competition began when Ms. Ericson decided to try to match the sit-up requirement her boyfriend had to meet in his training to be a police officer, and when Ms. Venable heard about this challenge from Mr. Boyles, she was up for it, too.

Now, although they don’t see each other often, the two consider themselves friends — bound by experiences such as the rug burns that result from their waist bands rubbing against their backs during hundreds and hundreds of sit-ups. But this pain is just one more test of how far they can push themselves and, maybe, one more example of endurance that will encourage others.

“Overall, this is just fun,” Ms. Ericson says. “But hopefully we’ll inspire other people to get out there and do something.”

Lifestyles reporter Erin Wisdom can be reached at ewisdom@npgco.com.