Here’s one more photograph from the March 2 1932 edition of the Toronto Daily Star, featuring a young man who was good at gymnastics.
Searches for Jack Holst didn’t turn up very much. There were other photographs of him from 1932 and 1933, and this page, which stated that he was the 1933 AAU high-bar champion. But he does not appear to have competed at the 1936 Olympic Games in Berlin.
The only other reference to him that I found was in Billboard magazine in 1947. He was appearing as a vaudeville act, performing gymnastics at the Loew’s State Theatre in New York. I have no idea what happened to him, but I assume that advancing age and the rise of television would have reduced his career opportunities.