Loek Alflen was born into a large family of 13 siblings. Like his seven brothers, Loek became a wrestler with Utrecht club De Halter, where they wrestled alongside Anton Geesink. The Alflens were good wrestlers, as no less than five of the seven brothers won at least one Dutch title. Loek Alflen was the most successful of them. He earned his first Dutch title in 1951 (beating one of his brothers), and would retain his title in the flyweight division through 1970. Loek Alflen was selected to compete at the 1956 Olympics in Melbourne, but just before the opening ceremony, the Dutch Olympic Committee decided to boycott those Games due to the Russian response to the Hungarian Revolt. Alflen did compete at the Olympics four years later, when he was eliminated after three rounds. Alflen, who worked as a carpenter, had three children. His daughter Tineke competed at a national level in taekwondo, while his son Rob played professional football between 1985 and 2000, twice winning the Dutch title with Ajax (although barely playing).