Some job applicants are fudging key details and even their recreational activities on their résumés. 

Résumé puffery is about as old as the résumé itself. However, a new survey shows job applicants are stooping to a new low--they're lying about their hobbies. In an effort to curry favor with hiring managers, applicants are making up fake hobbies and exaggerating their language abilities on their résumés and LinkedIn pages, according to a new survey from the language-learning platform Babbel.

Fourteen percent of Americans admitted to including on their resumes hobbies or interests that they don't actually have, according to the January survey of more than 1,000 Americans. The most common fake pastimes included: volunteering or charity work; running or staying fit; yoga or meditation; interest in photography, painting, or art; and playing an instrument. Similarly, one in eight Americans copped to lying about their fluency in a foreign language.

While making up hobbies may not be a deal breaker for some employers, it does present as less than ethical, which might be a red flag. Overstating language abilities may have even more acute consequences. 

"Language fraud could lead to problems in the workplace if a candidate is hired for a role in part (or entirely) because of their foreign language proficiency--which soon proves to be false," says Esteban Touma, a teacher at Babbel. "When a company relies on foreign language proficiency in a meeting or new business pitch, the failure to be able to speak fluently could prove humiliating--and result in lost business."

So how do you spot a faker?

Start with doing your due diligence. If a candidate claims proficiency in a language, set up an interview and assess his or her purported abilities. Touma points out that when someone is put on the spot during an interview, "it becomes quite clear if someone is fluent or not."

Online background checks and conducting reference checks also go a long way. It won't make much of a difference if candidates exaggerate their ability in playing the piano--so long as it's not integral to their role--but if their proficiency in a skill is paramount to their success, it can't hurt to verify it.