Gwyneth Paltrow stuffed her face while shooting drama Love Don't Let Me Down.
"She loves to eat. She pigged out," her trainer, Tracy Anderson, told UsMagazine.com at the Bent on Learning benefit in New York City Wednesday.
"She did gain weight. We took her training down from six days down to three days a week and she just ate whatever the hell she wanted," says Anderson of the formerly macrobiotic actress, 37, who blogged about downing fried chicken and ice cream sundaes on the Nashville set.
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"She ate all of the weight-gain culprits," admitted Anderson, who adds, "She loves bread and she loves cheese."
Now she's regained her sleek physique.
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"It's all off," Anderson says of the weight. "To get her back to shape, we bumped [her workout] back to six days a week."
The two do 45 minutes of dance aerobics and 45 minutes of Anderson's muscular design program (which includes swinging from bars on the ceiling). Anderson says her routine is intense enough for Paltrow to keep eating "fried chicken, cheese and bread."
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Another body change could be coming up for Paltrow, who said on the Ellen DeGeneres Show that she wants more kids. (She is mom to Apple, 6, and Moses, 4, with husband Chris Martin.)
"She is the most amazing mother ever," says Anderson. "She is the most beautiful person inside and out. She gets what life is really about. She gets the little special moments. She's the most charming and attentive mother. Anything could be going around and she's right there -- around her kids."