After getting upstaged by her sister in the sexiness department [1], Kim Kardashian [2] decided to take her sibling, Khloé Kardashian, on a mud run [3]. The pair, along with a female friend, donned black workout clothes and pink bandanas as they ran the obstacle course, which included a giant yellow slide that landed participants in a huge pile of mud. Kim clearly isn't taking it too easy as she prepares for her upcoming nuptials to Kanye West [4]. The pair are set to wed in May near Paris.

Source: Instagram user khloekardashian [5]

Source: Instagram user kimkardashian [6]

Source: Instagram user kimkardashian [7]

Source: Instagram user khloekardashian [8]