Ben Affleck and Jennifer Lopez are having the best time of their lives after deciding to give their relationship another chance, more than ten years after calling off their engagement.

But as their romance continues to rev up, the A-listers have reportedly hit a speed bump along the way.

A source revealed to OK! Magazine that the "Batman v. Superman" actor loves his girlfriend but refuses to do one thing for her - and that is in joining her on grueling morning workouts.

Jennifer Lopez is known to get up at 5 in the morning every day and work out for 90 minutes.

The source said, "Ben is a certified bedhead and not a morning person at all."

But there is one exception to the 48-year-old getting up early, and that's when he has to take his kids, Violet, 15, Seraphina, 12, and Samuel, 9, to school.

Early this month, the outlet further reported that the "Hustlers" actress alternates between dance workouts and core exercises in addition to weight training.

"Jen and Ben have a lot in common, but she's a fitness freak, and he sees working out as a necessary evil for when he's got to get in shape for a movie, like 'Justice League.'"

The source added, "Ben refuses to be dragged to the gym, and Jen's going to have a hell of a time getting him to change that!"

However, it doesn't mean that the mom-of-two wouldn't try.

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As the outlet also previously reported, the "Maid in Manhattan" star is determined to turn her boyfriend back into the hunky man he was before.

Per the source, while most couples' idea of a romantic date is going out to dinner and having movies, Jennifer Lopez's ideal date is hitting the gym with her beau.

"She works out every single day for at least two hours, which is what she had in common with Alex Rodriguez."

The source now thinks that with JLo also enforcing strict rules in her house, she might help get back Ben's six-pack in no time.

She already doesn't allow smoking in her home, so it's only a matter of time the "Gone Girl" actor would give it up and help the dad-of-three "be in the best shape of his life."

On April 15, Jennifer Lopez and Alex Rodriguez announced they have split officially, over a month after their initial split, and have gotten back together. A few days later, the Latin pop star was spotted with Ben Affleck.

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