He began training in the main sports club of Turku, where he befriended the legendary Finnish runner Paavo Nurmi, who helped Katz improve his technique.

[4] Katz competed for Finland in the 1924 Summer Olympics held in Paris, France in the 3000-meter steeple chase where he won the silver medal.

His coaching was on a voluntary basis in his spare time - he had hoped to find employment as a trainer, but was unpaid for his work and struggled to make a living.

He worked as a guard and maintenance man at the Maccabiah Stadium in Tel Aviv, a bricklayer on construction sites, and a traveling film projectionist for the British Army.

[4] In December 1947, as the Civil War in Mandatory Palestine was raging, Katz screened a film at a British military camp in the Gaza area.