Less than a year ago, the oxygen level in the 32-year-old cystic fibrosis sufferer’s lungs dropped to 16%, leaving him in intensive care, and in desperate need of a lung transplant.
In February, after two days on the donor waiting list, Mr Greenwood was given the lungs of Michael Boyes (25), a Wellington man who died after having a sudden brain bleed.
"I was organising an oxygen bottle at the same time as organising a flight."
Mr Greenwood said he did not know much about Mr Boyes, but what he did know was how different his life would be without his new lungs.
"In hindsight it could have gone either way.
"I might not be here if it wasn’t for such a quick time ...
"To get that call that quickly is pretty fortunate."
Yesterday, he was celebrating the annual Cystic Fibrosis Awareness Week by appreciating little things like breathing with ease.
"I think breathing gets taken for granted.
"I’m still trying to get used to breathing normally."
He believed awareness of New Zealand’s most common life-threatening genetic disorder was increasing.
"I think most people do know.
"There is a lot more understanding about it."
His new lungs allowed him to do "everything I couldn’t do and much more".
He had discovered a fondness for biking, and recently completed a 40km round trip to Portobello.
"It was a nice feeling having energy to keep going.
"I felt amazing when I got there, I just sat in the sun for about an hour and a-half."
Mr Greenwood said he not only gained new lungs and a new lease on life as a result of the transplant, but also a transplant twin.
A man he met while in hospital received Mr Boyes’ heart.
"That was quite nice to go through that with someone."
The "donor twins" kept in contact via Facebook, he said.
He would remain on anti-rejection medication for the rest of his life to ensure his lungs kept working, but believed his cystic fibrosis had done its worst.
He encouraged people to be organ donors.
"I’m an organ donor.
"I think they said my heart will be the best one.
"It’s been working a lot so it will be strong."
