Sandra Marlene Ruddick (née Anderson; September 3, 1932 – October 10, 2017) was an American artistic gymnast.

She competed at the 1956 Summer Olympics with the best individual result of 46th place on the vault and uneven bars.

She remarried Al John, she has a step-son Leo and Step daughter MaryAnn.

In 2012 she was inducted into the Indiana Gymnastics Hall of Fame.

This biographical article related to a United States artistic gymnast is a stub.