Creating a high-speed shutter effect

Hello...I very much like the high-speed shutter effect used in many action sequences (e.g. Gladiator) and sports footage where there's no blurring and an almost strobe-like feel is created in the action. I can create this effect by shooting in absolute bright daylight with the shutter cranked as high as it can go and the aperture opened wide.

Lately, I've been seeing horror/action movies that take place in near darkness (e.g. The Descent) and still have this same high-speed shutter effect. Can anyone explain how this is done with little-to-no light? Or is this an simulated effect created in post?

Thanks for any advice!