(BBC News) Riding on some types of roller-coaster is an effective way of removing kidney stones.
This is the conclusion of research that has won this year’s Ig Nobel Prize for Medicine.
The US researchers who carried out the work recommend that those afflicted with the condition should regularly use the theme park attractions.
The Ig Nobels are spoof prizes that are published in the Annals of Improbable Research.
Many of the topics recognised in the awards actually have a serious point to them.