Hazel finished 27th at the London 2012 Olympics, won by Jessica Ennis-Hill, before retiring from the heptathlon in September 2013.
However she is now back and planning a successful defence of the title she won at the Delhi 2010 Commonwealth Games at Glasgow 2014.
"I'm in better shape than I thought I was in. I'm really excited and I can't wait to get started," she told BBC Sport. "I was really pleasantly surprised by my tests. It's a thumbs-up for Glasgow, if I'm selected.
"I also have to chat to Commonwealth Games England to discuss the selection process and to see what hurdles have to be overcome. I wouldn't be doing this if I didn't think I could successfully defend my Commonwealth crown. I'm definitely targeting the podium."