GOALBALL
Rules: Played by two teams of three visually impaired athletes on an indoor court, the aim is to roll the ball into the opposition's nine-metre-wide goal before they have worked out where it is. Competitors wear eyeshades to allow participants with varying degrees of vision and the arena is silent so that players can hear the ball as it rolls towards them. The balls contains bells which the players can hear through the eight holes in its outer layer. Be there: Olympic Park - Handball Arena, August 30 - September 7. Tickets from £5.
SITTING VOLLEYBALL
Rules: Evolved from the German game Sitzbal, sitting volleyball is played along the same lines as its Olympic equivalent with a lower net (1.15m high for men, 1.05m for women). The aim is to land the ball on the ground in the opposition's side of the court and prevent the ball from landing in their own. A team is allowed three touches each before the ball has to be returned over the net, in addition to a legal block. A defensive passing shot which prevents the ball hitting the ground is called a "dig" and teams rely on a good "setter" to tee the ball up for an effective attacking shot. Be there: ExCel Arena, August 30-September 8. Tickets from £5.
