The players change ends at the end of the first, third, fifth game, and so on until the end of the set.
If the set ends and the total number of games played is even, then the players play the first game of the next set before changing ends.
If the number of games played in a set is uneven, the players change ends straight away.
They then carry on changing at the end of the first, third, fifth game as before.
In the professional game, players are allowed a 90-second rest between end changes.
This is extended to two minutes at the end of a set, although at the first changeover of the next set the players do not get a rest.
They are also allowed to leave the court to go to the toilet and can request treatment on court.