John Burkhill started Goole Judo Club in 1966 and has been running it since 1977.
Doing this in his spare time, he is also an employee at the East Riding of Yorkshire Council's Goole Leisure Centre, the judo club's meeting place.
Earlier this m
onth, ERYC's Human Resources department gave John a final warning about taking time off work.
But John claims that the only time he has had off work in ten and a half months was for bouts of colitis and gout, for which he takes medication, and also following a beating in August.
And he fears when he attends hospital in February for treatment on a nasal problem, he will be left without a job.
A petition to save John's future was started by club members during a judo championship held in Goole on Sunday.
John said: "It stinks. The judo world is up in arms and there is no way judo competitions in Goole would continue without me, it would finish.
"After all I have done I should be given an MBE instead of being treated like this.
"I have been getting swollen joints and was diagnosed with colitis which I take steroids for but they gave me high blood pressure, so it is all related despite them saying it isn't. "They are not interested in sport, just a number on a computer.
"I am scared to death to go the hospital in February in case I get the sack.
"I want to continue building judo in Goole and prepare kids for the next Olympics."
An East Riding of Yorkshire Council spokesman said: "Like any organisation, the council has to have policies and procedures for addressing absence.
"Our policy for short-term absence does contain formal warnings which take effect after a certain number of absences.
"The purpose of the warnings is to alert the employee to the fact that their level of absence is causing concern and that we want to work with and support them to reduce the number of absences."
