It is tempting to think that anyone who can do gymnastics beam can walk a tightwire on the first try - like switching from rollerblading to ice skating. However, while keeping the body "tight" keeps a gymnast on the beam, tight doesn't work for a tightwire, even without the wobble!
The key is to keep the big toe on the wire, the head up and the arms out And practice, practice, practice.
CirKids has two heights of wire: the low-low wire and the highwire. Both wires are actually wider (2cm) than normal performing tightwire.
