Britney Spears covers the June issue of Shape magazine, and the 31-year-old singer shows off her toned bod (and belly ring!) in a hot white bikini.

We always catch Brit at the gym, and she revealed what she does to stay fit. When asked specifically about her booty, she says, "I like it, then again, I hate it. I’m in my 30s now, so I have to work harder to keep it 'up.'"

Britney says she relies on yoga and the Nutrisystem diet program to keep her weight in check, but she said admits that it's hard. "Dieting is tough because my specialties are spaghetti, brownies and chocolate chip cookies," she says.

Gotta love her honesty!