Roger Barnes, a double world gold medallist at stick fighting and an exponent of Bruce Lee's martial art, Jeet Kune Do, was coaching another fighter at a martial arts tournament when he suddenly collapsed.

The JKD Northampton Club led by Mr Barnes, contained three other reigning stick fighting world champions as well as several medallists at the world, European and British championships.

One of his students, world silver medallist Damien Mills, whose fight Mr Barnes was watching last weekend when he collapsed, said: "I had the unpleasant task of telling the other students and there were a lot of upset people there.

"I can't overstate how highly regarded he was both as a teacher and as a person."

Students had told the Chronicle & Echo in the past that the reason they believed they were so successful was because of Mr Barnes' training abilities, saying he had made Northampton a "centre for stick-fighting".

A statement released by the club yesterday said: "Although he would be embarrassed to have us say it, he was one of the best stick fighters in the world, a fantastic teacher, a very humble and genuine man and a true friend."

Mr Barnes, aged in his late thirties, fought in the WEKAF Stick Fighting Championships at heavyweight in the veterans' category and was a multi-European and British champion, as well as current world champion.

He also practiced kung fu and achieved a black belt in the martial art of JKD-Kali.

Yesterday, personal trainers at Top Notch Health Club, one of the two Northampton gyms where Mr Barnes held classes, said they were shocked by his sudden death because of his extremely high fitness levels.

An inquest will be held to determine the cause of Mr Barnes' death.

All proceeds from last Sunday's event have been donated to the Barnes family by UAF Northampton and all JKD Northampton classes have been suspended as a mark of respect.