Horse racing was one of the many sports in Ancient greek, since females couldn't enter, it was suggested that they breed and take care of them. But taking care of the horses were costly, and females did not have the gender issue to raise a horse.
Kyniska sneaked in the horse racing, and won, she didn't get the award though, the owner of the horse did.
She won for another 4 years.Even though Kyniska didn't get to receive her reward, she got to put her statue declaring that she was the first female to win an all male olympics.
Kyniska's win was to inspire future female participants to try and enter the olympics
Sparta believed that healthy and intelligent women will give birth to stronger men. So Sparta encouraged women to become fit, and do excerise.