The former Mercy star told OK that she altered her lifestyle in order to get into optimum physical condition.
"I did hit the gym a little harder," she said. "Instead of eating pizza five days a week as my main [food] group, I cut it down to one day."
Trachtenberg further explained that she's pleased by the reaction that her Maxim cover has received.
"It's been very flattering. A lot of my friends like it or at least they have to say that," she joked. "It's funny because a lot of my closest friends are guys, it's... kind of weird that [they're] watching this."
The star made her acting debut at 3 years old in a Wisk advert and later portrayed Buffy Summer's supernaturally-created sister Dawn on Buffy The Vampire Slayer for three seasons.
Trachtenberg stars with Topher Grace in the upcoming film Take Me Home Tonight, which is released on March 4 in US cinemas and on May 13 in the UK.