It's difficult to capture action shots in poorly lit gymnasiums. Yesterday, I had to boost my camera's ISO setting to ISO 6400 in order to achieve a fast enough shutter speed (1/800th) to stop the action--even with my lens wide open.
When I first started taking pictures, I almost always used Kodachrome ASA 25 slide film. Sometimes, I would go with the higher speed ASA 400 film for night pictures. When desperate, I would try ASA 800--knowing that the quality was going to suffer severely.
As a perspective, the ISO 6400 setting that I used to take photos of my niece's volleyball match yesterday is 16 times more sensitive to light than the "fast" ASA 800 film that I used years ago. And, I would argue that the image quality of these ISO 6400 pictures exceeds that of the ASA 800 slide film.
Even so, I tend to convert images captured in low light conditions to black and white. Black and white removes all the crazy color casts from the gymnasium's lighting and also helps make the noise/grain appear more natural in my view.

I plan to return to this location on Tuesday with my Einstein strobes. This will raise the level of ambient light--allowing me to lower the ISO setting. Hopefully, supplementing the ambient light with strobes will result in higher image quality and more natural colors.