Peroneus brevis is a more effective evertor than peroneus longus

"A primary function of the peroneus longus and peroneus brevis is to provide the eversion moment necessary to balance the opposing inversion moments. "
The peronei have to be rehabilitated when injured, and they have to be strong to effectively control that rear and midfoot and work in a balance fashion. This is not a simple task and this will take some specific focused efforts, in our experience. On example we would strongly suggest would be to put far more focus on loaded weight bearing peroneal challenges in various heel heights rather that waste time with non-weight bearing band/theraloop work, it just cannot replicate the loaded rear/mid/forefoot.

Foot and Ankle. 2004 Apr;25(4):242-6.Peroneus brevis is a more effective evertor than peroneus longus.Otis JC1, Deland JT, Lee S, Gordon J.