Awareness of the ambient light is just as important as getting the right settings for your flash. If the flash is the main source of light, 1/60th will be enough to freeze the action. 1/60th is the time your shutter is open, NOT the duration that your flash is illuminated. This is much shorter than 1/60th. The light freezes he movement when it is much stronger than the ambient. If the ambient is bright enough, it will blur your shot with too slow a shutter speed. You need to strike a balance between ambient and flash, especially when using TV or Av with high ISO and Canon gear.

Isn't it a little late to be asking this question?