(Cover) - EN Star Style - Kim Kardashian has been going "crazy" at the gym in order to pull off an "epic" wedding day, according to sources.

The stunning reality television star is due to marry Kris Humphries this summer in a lavish ceremony, and has worked with top bridal wear designer Vera Wang to create her gown for the big day.

The 30-year-old star, who is famed for her enviable figure, is said to be intensifying her exercise routine ahead of the nuptials.

"She's been going crazy at the gym, working out at least twice a day, and with both of her trainers, as often as she can," a source told more! magazine.

"It's going to be epic. Not that we'd expect anything less. She only wants the best, or she has a fit."

It was reported last week that Kim had chosen her highly-anticipated wedding gown. The star is known for her stylish and elegant wardrobe choices, and the source added that Kim will be putting her eye for fashion to good use throughout the day.

"I think Kim's wearing three dresses on the day a Vera Wang to wear down the aisle, another to receive guests at the reception, and a sexier number for the evening," the source added.

Kim and Kris are reportedly taking dance lessons with a professional in order to perfect their first dance on the evening. According to the source, the pair are working with a TV dancer in order to impress their star-studded guest list.

"And the dancing will be perfect, because she and hubby-to-be Kris Humphries are taking lessons from Dancing With the Stars' Mark Ballas," the source revealed.

"It'll be a full A-list turn out too, with the likes of Justin Bieber, Beyonc and Jay-Z all expected to attend." (C) Cover Media