More than likely, your exposure- specifically your shutter speed settings- are too low. When you have fast action, you must have a higher shutter speed (Higher, meaning that the DURATION of the exposure is less. So, an exposure of 1/250th of a second is more desirable than an exposure of 1/30th of a second when shooting indoor sports. (This difference equates to about 400% more exposure, duration-wise). When shooting sports indoors, a "Fast" lens, meaning that the front of the lens is bigger, which allows more light into the camera at one time. (This normally equates to "F-Stop" settings. So, a 50mm F1.4 lens will be a "faster" lens than a 50mm F2 lens. The lower the F number, the "faster" the lens. This also equates to higher prices...) Another consideration for shooting stop-action sports photography indoors is using higher ISO settings. When you double the ISO number, you cut the amount of light required to make a good exposure in half. So, ISO 200 requires half the light of ISO100, and 400 requires half the light of 200 and so on. Typically, I use a setting of ISO 800 or higher for indoor sports (Which, BTW is my speciality...). The trade-off for using higher ISO settings is that it introduces more noise into the image, which many people find less desirable. I also wrote a few articles for POPULAR PHOTOGRAPHY & IMAGING about shooting sports. The "football" article will more than likely be the most help to you. Basically, ALL sports photography is shot the same way, and if you use these techniques, your work will greatly improve. Here is a link to those, and hope they help!