In London she used the hands that so delicately played the piano to throw both the shot and the discus. In her first event, the discus, Ostermeyer was in third place with only one round left. However, her final throw of 41.92m gave her a victory of 75cm. Four days later, she earned her second gold medal by winning the shot put by 66cm. Finally, she competed in the high jump and earned a bronze medal behind high jump specialists Alice Coachman of the United States and Dorothy Tyler of Great Britain.
Ostermeyer celebrated her shot put victory by performing an impromptu Beethoven recital back at the French team headquarters. Her success in athletics actually hurt her reputation as a concert pianist, and for the next six years she was afraid to play Liszt because he was too "sportif." However, Ostermeyer continued to defend her "divided life." "Sport," she said, "taught me to relax; the piano gave me strong biceps and a sense of motion and rhythm."