Could you help me with this?

[I like English]

Dear Teachers,

I was reading a passage about Olympic games and I came across to a sentence that I did not quite understand. Could any one explain this for me? See the following sentence.

Boxers did not use their fists. They wrapped their hands with ox-hide thongs and slapped one another with the flat of the hand. What does ox-hide thongs here mean? Thanks in advance!

Emily

[Casiopea]

Welcome, Emily.

A narrow (possibly plaited) strip of leather.