A shinai is a training sword built from four bamboo staves bound together with cord and leather fittings, shaped and balanced to represent a Japanese sword while being far safer to strike an opponent with than a solid weapon. It is the implement used for kendo's live sparring, known as keiko or shiai depending on context, where full speed strikes to permitted target areas are exchanged.
Because a shinai flexes and its bamboo construction absorbs some impact, it allows kendo to include direct, full speed contact sparring in a way that would not be safe with a rigid bokken. Shinai need regular inspection, since bamboo staves can splinter or crack with heavy use, and a damaged shinai is generally retired or repaired before further sparring, since a broken stave can cause injury.
Shinai are always used together with full protective armour. See our kendo equipment guide and the entry on bogu for the armour worn alongside it.
