Adolf Lindfors, a baker by profession, took up wrestling when he was 20-years-old and soon rose to be one of the top Finnish heavyweight wrestlers. Lindfors made his international début before World War I, at the 1911 World Championships, where he won a silver medal in heavyweight behind Yrjö Saarela and also competed at the 1912 Olympic Games but had to retire due to injury. The high point of Lindfors’ career was at the 1920 Olympics, where he won the Greco-Roman gold medal when he was 41-years-old. While he was wrestling in the final match, his wallet containing a considerable amount of money was allegedly stolen from the locker room.
Domestically, Lindfors represented Porvoo Achilles, the Helsinki Athletic Club and the Porvoo Friends of Sobriety Gymnastics and Sports Club. He was Finnish Greco-Roman heavyweight champion in 1905, 1907, 1910 and 1913, runner-up in 1904, 1908, 1909, and 1915 and placed third in 1912. He also won the Finnish weightlifting championship in 1903-04. Lindfors was also the founder of Porvoon Akilles in 1902 and served as their first president from 1902-12.