Fit for fatherhood! That’s Rob Kardashian's aim. The reality TV star told his Instagram fans late on Tuesday, October 18, that he’s determined to get back in shape after the birth of his first child with Blac Chyna.

The couple are due to welcome their daughter next month and Kardashian insists they’ll then be battling the bulge together.

“Oh yeah we snapping back lol,,, baby will be here in 4 weeks and I'm done with carrying this pregnancy weight,” he captioned a throwback picture of them at their slimmest. “Me and my baby gonna be righttttttt ,,, MOTIVATION TIME! we almost there Chy.”

He then complimented his fiancée’s bikini-clad photo: “FAAAAACK Chy looks so bomb here aghhhh.”

The 29-year-old Arthur George sock designer recently got candid about his insecurities on his E! show Rob & Chyna.

During a frustrating and unsuccessful shopping trip to buy a pair of jeans. he said: “Even when I was in the best shape of my entire life, I still had an insecurity with my weight,” he confessed. “On top of that, there’s paparazzi people [who] follow me and get pictures of me and that shuts me down too, like, not wanting to go out.”

He added: "I’m not feeling my best. I’m not comfortable with my skin. I’m not comfortable with this weight, so I feel like I’m not happy with anything I do right now."

The dad-to-be has struggled with his weight for years, but has branded Chyna his “motivation” to shed the pounds.

In April he happily revealed he had already dropped 50 pounds from his 298-pound frame, but said he had a “goal weight” of 200 to 205 pounds.

On Tuesday, October 11, Chyna revealed she had gained 50 pounds during her pregnancy so far.

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