“Not only were women not permitted to compete personally, married women were also barred from attending the games, under penalty of death. (Maidens were allowed to attend.)
Pausanias tells the story of Callipateira, who broke this rule to see her son at the Games:
She, being a widow, disguised herself exactly like a gymnastic trainer, and brought her son to compete at Olympia. Peisirodus, for so her son was called, was victorious, and Callipateira, as she was jumping over the enclosure in which they kept the trainers shut up, bared her person. So her sex was discovered, but they let her go unpunished out of respect for her father, her brothers and her son, all of whom had been victorious at Olympia. But a law was passed that for future trainers should strip before entering the arena. (Pausanias 5.6.8ff)
Athletic competitions for women did exist in ancient Greece. The most famous was a maidens’ footrace held at Olympic Stadium in honor of the goddess, Hera. There were three (3) separate races for girls, teenagers, and young women.
The length of their racecourse was shorter than the mens’ track; 5/6 of a stade (about 160 meters) instead of a full stade (about 192 meters). The winners received olive crowns just like Olympic victors.”
[snip] In the comedy Lysistrata by the Athenian playwright Aristophanes, a group of Athenian women crowd round a Spartan woman called Lampito. ‘What a gorgeous creature,’ they say. ‘What healthy skin, what firmness of physique.’ And one of them adds, ‘I’ve never seen a pair of breasts like that.’ To which Lampito proudly responds, ‘I go to the gym. I make my buttocks hard.’ [unsnip]
http://www.channel4.com/history/microsites/H/history/n-s/spartans2.html