Jewel and Nancy O'Dell Withdraw from Dancing

Photo: Kevin Mazur/WireImage; Jon Kopaloff/FilmMagic

Singer Jewel and Access Hollywood host Nancy O’Dell are withdrawing from participating in Dancing with the Stars, ABC announced Thursday.

Both women have suffered knee injuries during rehearsals in recent weeks. Jewel, who originally was told she had tendonitis, was actually diagnosed with a fractured tibia in both legs. O’Dell has a torn meniscus that will require surgery.

“Both Nancy and Jewel were training hard. They just threw themselves into it,” Dancing executive producer Conrad Green tells PEOPLE. “It’s rather unfortunate that the most committed to the show were doing harm to their bodies. I believe both injuries came from overtraining, particularly in the early stages.” Green says he’s convinced that the women’s fitness levels (both are avid fitness enthusiasts) may have ultimately done them in.

“This is now three fit women, if you include Misty May-Treanor from last season, who had to withdraw from the show,” Green says. “Perhaps who are fitter throw themselves into it with more wild abandon. I really feel for them and we may need to take a look at how hard train in the future.”

In a press release issued by the network, both women expressed their regret in having to pull out of the competition days before the season was about to begin.

“When the doctors told me my injuries were so severe that I couldn’t walk, let alone compete, I was devastated that I couldn’t continue the show,” Jewel said. “I have every intention of being at Dancing with the Stars this season supporting my husband, Ty Murray, and his partner, Chelsie Hightower. I hope to be back on the show in the future.”

“Beyond disappointment doesn’t even being to describe how I feel about not being able to continue on Dancing with the Stars,” O’Dell says. “It has been one of my favorite shows since Season one! But I have torn the meniscus in my knee in two places, which requires surgery. Dancing with the Stars was a great experience. I’ll miss working with my partner, Tony Dovolani, and all the other wonderful on the amazing production that is Dancing with the Stars.”

Green says both women hope to come back to the show and give the ballroom another try. Meantime, Green confirms that “casting changes” will be announced live on the season eight premiere on Monday, March 9. –Monica Rizzo

Kevin Mazur/WireImage; Jon Kopaloff/FilmMagic