Mackenzie Douthit is in great shape.

'Teen Mom 3' Star Mackenzie Douthit Shares Photo Of Post-Baby Body

Since giving birth to her second child nearly one year ago, the Teen Mom 3 star has been hitting the gym regularly and eating right, and according to a new Instagram photo, her hard work has paid off.

"Fitness model in the work," Douthit wrote on Instagram on Saturday. "Excuse me looking like a mess I just got back from a long run. check out my latest YouTube cardio video and get fit with me. Less than six minutes long you can do it!!!!"

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Douthit, who is married to Josh McKee, the father of her two children, was featured on MTV's 16 & Pregnant in 2013, and Teen Mom 3 months later. However, unlike the stars of Teen Mom and Teen Mom 2, Douthit and the rest of the cast, which also included Katie Yeager, Briana Dejesus and Alexandria Sekella, failed to gain the viewers needed to move on to a second season.

Now that she has more time on her hands, Douthit has been focused on becoming a fitness model, and keeping fans in the loop with her progress. Douthit was always an athlete, so living healthy is nothing new, but these days, she's going extra hard in hopes of accomplishing her dream.

She's even been making her own videos, in which she gives fans a look into her workout routines.

Below is Douthit's latest cardio video.

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