SHARE 4 COMMENTMORE

KUSA - Your memory-foam mattress might be great for your back, but if one study is any indication, the opposite might be true for your sex life.

Some memory-foam users told researchers that sex on memory foam mattresses was akin to being "stuck in quicksand," and that it was "uncomfortable," "difficult" and even "horrible."

"There's a lack of resistance for the knees and feet," New York sex therapist Sari Eckler Cooper told Barron's. "And whoever is on the bottom is sinking into the bed."

The study also found that memory-foam owners are intimate less frequently, and sometimes even resort to having sex at other household locations. Researchers say that when people buy mattresses, they often think about comfort before their sex lives.

"We believe the findings perfectly mirror a lack of awareness about the mattress physics necessary for comfort, support and the energy giveback needed for both intimate experiences and total restful sleep," said Mark Quinn, Segment VP Marketing at Leggett and Platt, in a news release.

The study was commissioned by traditional mattress giant Leggett and Platt. Consumers were asked to evaluate the performances of various mattresses, and then share their sexual experiences on those mattresses with various researchers.

The market share for memory foam mattresses jumped from 14 percent to 20 percent between 2004 and 2012, according to a 2012 Barron's article.

This increased market share, the article added, has led some traditional mattress companies to emphasize the intimate benefits of their products over memory-foam mattresses.