Maria Polyzou has shaken off the problems that came up on her second day of running the Pheidippides route from Athens to Sparta and back and by Wednesday evening she was only 50 kilometres before Sparta.

The determined 42-year-old runner had suffered from problems on her knees and with other minor injuries as well as blisters - typical of such ultramarathon races - but on Wednesday her spirit was back on a high and she vowed to go on until the end.

Her pace is on schedule, too, as she had planned to reach Sparta for Thursday, and barring a significant problem she will be at the Peloponnesian city on Thursday afternoon.

On Wednesday morning she passed what is probably the most difficult section of the course, the Artemisio mountain near the city of Tripolis and has now completed just under 200 kilometers since Monday morning when she left Athens.

Polyzou, the Greek record holder in the marathon and Director of the Museum of the Marathon Run, has planned to cover the 540-kilometre distance to Sparta and back, hoping to reach the Tomb of Marathon by Sunday evening.

She is boosted by the support that residents of the areas she passes by give her, with her husband, Apostolis Mavrogiannis recounting what happened on Tuesday at the village of Malandreni.

"Some villagers had come out of Malandreni to see Maria run and asked her whether she needed anything, whether she wanted some food and so on. Maria was pleased to see their genuine interest and said she would love some chicken with spaghetti.

"It was a family named Kyriakopoulos who rushed back to their village and prepared a home-made meal as Maria had wanted it in exemplary hospitality, stating their pride for what Maria was doing. It was really moving," said Mavrogiannis.

Polyzou decided to revive the feat of ancient messenger Pheidippides on the occasion of the 2,500-year anniversary of the Battle of Marathon, in 490 BC. If she manages to finish this grueling run she will become the first woman ever to do it.