The transfer of the private business to a charitable trust is believed to be the first of its kind in Scotland.
Profits from the gym will now go to the Accord and St Vincent's hospices, in Renfrewshire.
Health and fitness expert Alex Whelan, 58, has decided to gift his Pro-Life Fitness Centre gym, in Paisley, to the Renfrewshire Sports Charity as he retires from running the operation he founded 24 years ago.
Mr Whelan has granted a licence for the charity to run the Pro Life gym and the new charitable trust is hoping to raise £500,000 in the next five years. The charity's trustees have also set up a fund to help young sportsmen and women achieve their goals.
"As a long term supporter of both hospices, I know how much they appreciate the support of the community and I am delighted to be able to help in this way," said Mr Whelan.
"Existing Pro-Life members and anyone who joins from now on can feel proud they are helping two such worthwhile charities and perhaps some sporting stars of the future.
"Every pound profit will go to the new trust."
Helen Simpson, chief executive of Accord in Paisley, said: "We are extremely grateful to be considered for sponsorship. All monies we receive will be appreciated by patients and families dealing with a life-limiting illness."
Kate Lennon, chief executive at St Vincent's Hospice in Johnstone, said: "We feel very privileged to be in this position and for the two hospices to be involved.
"As well as helping raise cash for us, Renfrewshire Sports Charity will also be able to support up and coming young sports stars, which is wonderful."