Reese Witherspoon On Her 'Wild' Backpack & How Heavy It Really Was — VIDEO EXCLUSIVE

Reese Witherspoon hated the 70 pound backpack she wore as Cheryl Strayed in Wild . And who can blame her? The pack, nicknamed "Monster," was worn constantly, and left her back sore and body drained after the long days. She said of the luggage, "The first couple weeks were horrible and I hated Monster, and I’d kick it every time, and I would take it off my back every single time after he’d say cut. And then after five weeks I just got so used to it. It was like an appendage."

Based on Cheryl Strayed's Wild: From Lost to Found on the Pacific Crest Trail, the book and film detail the real life journey of a woman on a 1,100-mile hike on the Pacific Crest Trail in a journey of self-discovery after a divorce and the loss of her mother.

In an exclusive behind the scenes clip from the film, we see author Cheryl Strayed talk about the real Monster, and Reese Witherspoon describe exactly how it felt to be burdened with the prop — not to mention when director Jean Marc-Vallée decided her pack didn't look heavy enough, and added more weight. Take a look at the clip below.

Wild is on BluRay and DVD now.

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