Along with fellow 1948 Olympians Brenda Helser and Nancy Merki, Zimmerman was part of the Multnomah Athletic Club team dubbed "Cody's Kids" that from 1939 to 1948, won 58 individual national swimming titles and three national team swimming championships.
Alongside fellow 1948 Olympians Brenda Helser and Nancy Merki, Zimmerman was a member of the Multnomah Athletic Club team known as "Cody's Kids," which dominated national swimming competitions from 1939 to 1948, claiming 58 individual titles and three team championships.