When it comes to freezing motion, shutter speed is normally the parameter of choice. However, if you are shooting in the studio and you have full control of the light, using flash can actually be the better choice. This excellent video tutorial will show you how to freeze motion using flash.
Coming to you from John Gress, this awesome video tutorial will show you how to freeze motion using flash. As the video discusses, one of the most important things you need to pay attention to is the flash duration. This is essentially a measurement of how long it takes the light to output the majority of its power. When you are attempting to freeze motion using the flash, you will want this duration to be as short as possible. This duration will normally be expressed as the t.1 or t.5 values, which express how long the output is above 10% the maximum value or 50% the maximum value, respectively. This duration usually varies with the output power of the flash, so be sure to consult your flash's manual to ensure you are using the right settings for the image you are trying to create. Check out the video above for the full rundown from Gress.