Credit: Instagram

Hard work pays off, y'all! Just look at Teen Mom's Tyler Baltierra, who has been hitting the gym hard throughout the past few months. The 21-year-old reality star and fiancé to Catelynn Lowell posted a before and after picture of his progress on Instagram, and we have to say he's really looking great!

Credit: Instagram

"4 months of progress...feelin pretty good!" he wrote on June 16, along with a before and after picture of his abs. "#motivated #determined #HIHATERS."

No hate here, Ty! We're digging your new outlook on health and fitness, and admire your determination. We can already see more muscle definition since his last shirtless selfie, which he posted back in April. All those intense workouts are really paying off.   

Our best guess is that Tyler's getting in tip top shape for his upcoming wedding to Catelynn, which is scheduled for July 13, 2013, the 9th anniversary of the day they started dating. Be sure to keep your eyes peeled for updates on their pending nuptials (and more shirtless pics of Tyler, of course!).

What do you think of Tyler's new and improved physique? Tell us your thoughts!