You got the older athlete, jmd. It is Emil Zatopek who was born 90 years ago today. Of course you know that his wife, Dana, was born the same day in 1922 and also won an Olympic gold medal on the same day that Emil won the 5,000 meters in Helsinki (July 24, 1952). They had been married in 1949.
Now, who is the younger athlete with four Olympic gold medals?