Graham, 28, who lives in Park Slope, Brooklyn, and is "a size 14 or 16, depending on the day," stays in shape by putting up her dukes and working up a sweat. "I love boxing. I have a local gym," she said.
The model is one of three 2016 S.I. Swimsuit Issue cover girls — a first in 52 years for S.I. — along with fashion model Hailey Clauson, 20, and mixed martial artist Ronda Rousey, 29.