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One For The Girls - Best Bodies At The Summertime Ball 2012
3. Justin Bieber
The Canadian teen star is a basketball fanatic and being one of the world's most photographed stars - it means he's always on the move. The singer tries to eat healthy and keep up with his mentor Usher's toned abs. The singer also recently spent time with boxing star Mike Tyson in the gym as he showed off his quick jab and impressive fighting skills.