A gym bunny：
Someone who spends a lot of time exercising in the gym, and who cares very much about the shape and condition of their body.
“A gym bunny 一只健身兔” 用精力旺盛、蹦来蹦去的兔子来比喻 “一位非常关注自己的体形体态、酷爱健身的人”。“A gym bunny” 也可以用来暗示一个人 “比较虚荣，过分在意自己的外貌”，这个用法带有贬义色彩。
例句
Robbie is such a gym bunny! He spends more time at the gym than he spends at home.
罗比真是个健身迷！他在健身房里的时间比待在家里的时间多。
I could never be a gym bunny! I like chocolate cake and sitting on the sofa too much.
我永远都成为不了一名健身健将！我喜欢吃巧克力蛋糕，也喜欢坐在沙发上。
You don’t have to be a gym bunny to start seeing some changes in your body. A little exercise can make a big difference.
你不必成为一名健身狂热者，就能看到锻炼让身体产生的变化。做一点运动就能看到很大的不同。
