Complex sentence: His passion for drawing did not prevent him from being devoted to fencing at the same time: he was Champion of Belgium in 1912, gold medal winner at the Olympic Games of Stockholm in 1913, and World Champion in 1914.
Split into simpler sentences: His passion for drawing did not prevent him from being devoted to fencing at the same time. He was Champion of Belgium in 1912, gold medal winner at the Olympic Games of Stockholm in 1913, and World Champion in 1914.