Rosenfeld competed in the Olympics in Amsterdam in 1928. This was the first time that women were allowed to participate in track and field events at the Olympics. She was a member of the Matchless Six, the Canadian women’s track and field team. This team placed first in the 400-metre relay, won the gold medal and became national heroes. Rosenfeld also won the silver medal in the 100-metre dash and placed fifth in the 800-metre race.