Personal trainer Jenna Foster has been running for the last decade, so when it was time for her yearly 5K, she didn’t hesitate to sign up — despite having just given birth.

“I exercised throughout my recent pregnancy, as well as my pregnancy with my daughter 11 years ago,” the Maryland native tells PEOPLE. “I had a short, speedy natural delivery in July. I pushed for 13 minutes and gave birth to a healthy boy!”

With all that in mind, she floated the idea by her obstetrician-gynecologist and “was given the okay” to “walk or jog” the race with her son. Her daughter and husband also joined the race.

Foster, 33, began the race running with her stroller, but then her son started crying and wouldn’t stop.

“I knew he needed to eat. There’s a distinct cry when he’s hungry, and I didn’t want to make him wait that long,” she shares. “I also knew I had to stay with my daughter, and she really wanted to finish the race. She pushed the stroller while I nursed my son, and we walked together towards

“Since my husband finished about 20 minutes ahead of us, he was able to run back to us and help out,” Foster adds.

With her husband pushing the stroller, the family crossed the finish line together.

“I had a lot of emotion getting to cross the finish line with my family,” Foster says. “This was my daughter’s first 5K, and now my son’s as well.”

Making the race even more emotional was the fact that the course went down the street where she grew up with her grandmother.

Foster notes that she made sure that her newborn son was safe and walked during the race when she had to nurse, never running with him in her arms.

“I really didn’t think I was going to have to nurse him, but when you’re exclusively breastfeeding, you never really know what to expect,” she says.

The mother of two later shared a snippet of the experience on her Instagram account, showing her nursing while walking toward the finish line.

“We set out to finish the race, so that’s what we did. With a fed baby,” she wrote. “48 minutes, carrying my son half of the time. Not my fastest finish, but I’m calling this a PR for sure.”

Foster felt like it was funny and relatable story for other moms, showing the unpredictability of motherhood.

“You just can’t have expectations, and even when you try to make time for yourself, your children come first,” she tells PEOPLE. “You just have to adapt in the moment. I really didn’t have time to think about what to do in the race. We just kept moving forward.”

She hopes that other parents know that “you can still take care of yourself and move your body when you have children; it might just look different for a while.”

The mother of two later shared a snippet of the experience on her Instagram account, showing her nursing while walking toward the finish line.

“We set out to finish the race, so that’s what we did. With a fed baby,” she wrote. “48 minutes, carrying my son half of the time. Not my fastest finish, but I’m calling this a PR for sure.”

Foster felt like it was funny and relatable story for other moms, showing the unpredictability of motherhood.

“You just can’t have expectations, and even when you try to make time for yourself, your children come first,” she tells PEOPLE. “You just have to adapt in the moment. I really didn’t have time to think about what to do in the race. We just kept moving forward.”

She hopes that other parents know that “you can still take care of yourself and move your body when you have children; it might just look different for a while.”