She is currently President of the EF Education First cycling team.
She was previously the President and Chief Executive Officer of New York Road Runners (NYRR) through May 18, 2015.
Wittenberg oversaw the TCS New York City Marathon and several other races, events, and programs that draw over 300,000 yearly participants.Under Wittenberg's leadership, NYRR helped develop new initiatives such as the World Marathon Majors Series and several community programs that have introduced running to underprivileged children.
For her efforts related to the TCS New York City Marathon, an article in the New York Times stated that Wittenberg "has transformed the New York City Marathon from traditional to competitive to innovative."A former competitive runner, Wittenberg won the 1987 Marine Corps Marathon.