Kolesar retired from professional football after one season to pursue a medical career, and later established a practice in Saginaw, Michigan.

A native of Cleveland, Ohio, Kolesar attended John Adams High School before graduating and enrolling at the University of Michigan.

[2][3][4] The 1942 Wolverines' line, which included Kolesar, Julius Franks, Al Wistert, Merv Pregulman, and Elmer Madar, became known as the "Seven Oak Posts".

"[11][12] At the end of the 1942 season, Kolesar and Michigan quarterback George Ceithaml were invited to compete in the annual Blue and Gray Game at Montgomery, Alabama.

Kolesar said at the time that he would continue his medical studies while playing for the Lions; he said he would be able to practice three days a week and would be available for weekend games.