Myotonics, sometimes referred to as Fainters or Stiff Legged Goats, have a genetic disorder called Myotonia Congentia.
Myotonia is a condition that causes their muscles to freeze for about 10 seconds when a goat is surprised.
This "freezing" of muscles may cause a young goat to fall over, but is so totally harmless that many goats will even continue to eat or chew while falling over.
Besides being a novelty, Myotonia is a condition that also helps to build muscle in Myotonics leading to a higher meat ratio per pound. Myotonia also prevents Myotonics from being fence jumpers or escape artists.