A native of Kaylor, Pennsylvania, Stydahar grew up in West Virginia and played college football and basketball for the West Virginia Mountaineers. He was drafted by the Chicago Bears in the first round of the 1936 NFL Draft and played nine seasons as a tackle for the Bears from 1936 to 1942 and 1945 to 1946. He was selected as a first-team All-Pro five consecutive years from 1936 to 1940 and helped the Bears win NFL championships in 1940, 1942, and 1946 NFL Championship Games.