He is nicknamed the “Ilocano Shark,” Yldefonso made his country proud when he became the only Filipino to ever win multiple medals in the Olympics.
A three-time Olympian, he won his first bronze medal in the 200-meter breast-stroke event at the 1928 Amsterdam Olympics while his second came during the 1932 Los Angeles edition. His third and final appearance saw him place seventh at the 1936 Olympics held in Nazi Germany.
He also became known as the “Father of the Modern Breast-stroke” after he made the style more efficient by bringing the stroke closer to the surface.
Source: https://filipiknow.net/forgotten-filipino-athletes/