The 20-year-old explained that he has been boxing to buff up and prove that he is no longer "that wee boy" who finished third in X Factor's 2008 series.
"I've got a lot taller and my hair's shorter. I'm not as chubby as I used to be," he said, revealing: "I once boxed in an Irish championship."
Quigg also suggested that he would have preferred to enter The X Factor now rather than in his teenage years.
Asked if he regretted taking part in the show, he replied: "Not one bit. I had the best time of my life. The only thing I'd say is, it might have been better if I was the age I am now.
"I was the youngest ever to get to the final. One Direction came after me. I was so young I didn't really understand what was going on."
Quigg went on to admit that he still gets plenty of female attention due to his X Factor stint - even though he is holding out for a romance with his former judge Cheryl Cole or 2011 winners Little Mix.
"All my friends love it. It's very flattering... I do [want to settle down], but stuff like having kids is a long, long way away."
Read the full feature in Now magazine, out today (October 9).
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