Martial arts maneuvers are often amazing to behold. The power and insight into the physical and metaphysical that such feats of performance require sometimes border on the impossible, but at its core, a martial arts maneuver is still nonmagical. Martial arts cannot punch holes in the fabric of reality, cannot curse you, cannot set you on fire, cannot grant spell resistance. Martial artists may have a degree of inner power, but it is not magic. As such, the effects that they cause are bounded by the laws of physics. What other races of beings may consider as 'ki', or 'that physical energy that lets you blast stuff', is in fact better explained as 'the act of focusing all of your body's power in a single point'. The effects of such Ch'i are bewildering to the point of making you doubt reality, but are always nonmagical, extraordinary abilities.
As a note for people interested in making such maneuvers, do note that anything that might resemble a supernatural or spell-like ability is therefore not a proper martial arts maneuver.