Paul Fisher said his brother worked as a storeman in Wellington and his workmates told of him being able to carry heavy carpet on his own, up eight flights of stairs.
"He is the hardest working person I know."
Peter Fisher's rate of progress has been such that he is due to be transferred to a rehab unit on Monday.
His brother said Peter was eating pureed food and was starting to get his appetite back.
"He is still sleeping for massive hours but that is part of the healing process."
The family and Peter Fisher's partner Freida have been almost constantly at his bedside.
Paul Fisher said his brother had given up smoking six months ago "after trying to for years" and the family have credited that with helping his recovery.