Claes Egnell was a very versatile athlete who took part in Olympic Summer and Winter Games, in the latter in the demonstration sport of winter pentathlon, which was only held in St. Moritz in 1948. He was the only one of the four Swedish participants who did not finish the event, although he was in fourth place when he was forced to withdraw due to a complex fracture of his leg suffered in the downhill skiing event, which had doctors concerned that they might have to amputate his foot. He recovered, however, and in the same year, also took part in London in shooting and four years later in Helsinki was a member of the Swedish team that won silver in the modern pentathlon team event. In addition to his Olympic sports, Egnell also competed in fencing, ski running, tennis and horse riding
A newspaper in his native Örebro awarded Egnell a medal as early as 1939 for being the best known personality in local sports. In1945 he received the renowned Svenska-Dagbladet-Medal for winning two Swedish Championships after struggling hard to come back after a severe injury. From Örebro he moved to Falun when he was appointed Secretary-General of the World Ski Championships there in 1974. Until his death he remained devoted to modern pentathlon and was a guest of honor at the World Cup final in Uppsala in 2005.