Education
In 1956 he entered the Greco-Roman contest instead and finished fifth.
In 1956 he entered the Greco-Roman contest instead and finished fifth.
Antonsson took up wrestling at age 14, began competing aged 17, and retired at 47. In retirement, for many years Antonsson headed his native club Trollhättans and refereed wrestling competitions.
He competed at the 1948, 1952 and 1960 Summer Olympics in freestyle wrestling and won silver medals in 1948 and 1952. Besides Olympic medals he won three world, two European and 24 national titles. At the 1953 World Greco-Roman Championships he dominated the reigning Olympic champion Johannes Kotkas, who was 30 kg heavier than Antonsson. He won the word title and was awarded the Svenska Dagbladet Gold Medal later that year.