When I lived in , Ethiopia, I played badminton and squash. The reduced air resistance at 2600 metres altitude makes a perceptible difference to the flight of a shuttlecock: it travels much further. Should there also be a noticeable difference to the flight of a squash ball? If there is an effect it is less noticeable, but my squash partners and I would like to think that it exists, rather than admit age and a lack of fitness are slowing us down.
Mark Harvey, London, UK