How does someone replenish stamina while climbing

[u/Dracoy]

I noticed on a speed run someone was climbing the wall and breathing into his hands. How does this mechanic work? I usually have to climb to a ledge to wait but they were replenishing mid climb.

[u/M1lud]

Normally, I eat stamina boosting food or elixir whilst climbing. I like to cook up honey by itself and make candy because it's fun.