Wheelchair tennis
The sport that fits most easily into an ordinary week, because it needs nothing special from the venue. It is played on any standard court with normal rackets and balls, and the only rule change is that a wheelchair player may let the ball bounce twice before returning it.
That makes mixed games with non-disabled friends genuinely workable, from a casual hit to a doubles match. Venues and events running sessions typically have sports chairs for new players to borrow, so you can find out whether you like it before spending on a tennis chair. In Great Britain more than 50 venues run wheelchair sessions, listed through the LTA.
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