Evan Agostini / Invision/AP 1 / 10
Evan Agostini / Invision/AP 1 / 10

Not so romantic! Reese Witherspoon revealed to Us Weekly at the premiere of her new, buzzed-about film "Wild" at the Toronto International Film Festival on Sept. 8 that her date nights with husband Jim Toth consist of calculators and pencils.

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"Our date nights are mainly helping our kids with homework," the blond mom to Ava, 15, Deacon, 10, and Tennessee, nearly 2, told Us. "And then, going to sleep," she added, laughing.

Despite a not-so-hot date regimen, the Oscar winner was regardless confident to get naked for an intense sex scene in her new adventure-drama.

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When asked about the scene in "Wild," Witherspoon told Us, "I think it's a really brave film in that ... it tells women not to be embarrassed or ashamed about their bodies."

Witherspoon has been generating early Oscar buzz for her portrayal of author Cheryl Strayed in the flick, which follows her real-life 1,100-mile solo hike she takes in hopes of a fresh start after her mother's death and failed marriage.

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"I definitely was strong after [filming] and it was great to be outside and experiencing nature," Witherspoon told Us of the challenging role. "There's no makeup in the movie and there was no looking at yourself while filming [either], all the mirrors were painted black in the trailers."

As for that backpack she totes around the whole time, the actress told Us, they couldn't fake it! "The backpack really had to be very heavy," she said. "You could tell if I was cheating so we made it very heavy."