Which preposition to use with gymnasts

in Occurrences 5%

This man had taken his degree at Heidelberg, and the Germans are the finest gymnasts in the world.

as Occurrences 1%

Born of humble parentage, and contending in his earlier years with the extremest poverty, he completed a theological education, became a tutor, volunteered in the Danish navy, travelled in France and England, and began his career of gymnast as a fencing-master in Stockholm.

on Occurrences 1%

"And I am to stand on top like a gymnast on a sphere or be rolled under," thought Jack.

than Occurrences 1%

There are spiritual diseases which coil poisonously among distorted instincts and disordered nerves, and one would be generally safer in standing sponsor for the soul of the gymnast than of the dyspeptic.

Which preposition to use with  gymnasts