Why was the stadium at Olympia moved eastward in the 4th century BCE?

In the mid-4th century BCE, the stadium at Olympia was shifted approximately 270 feet (82 metres) eastward to physically separate the athletic venue from the sacred precinct, known as the Altis.1

Prior to this relocation, the stadium was not enclosed, and one end of the track sat directly in front of the great ash altar of Zeus. By moving the stadium eastward and constructing a western embankment—parallel to the newly built Echo Colonnade—the organizers effectively cut the stadium off from the sanctuary. This architectural change created a distinct boundary between the religious space and the athletic facilities, with access between the two areas subsequently maintained only through a formal, covered entrance known as the Krypte.1