While reading I came across a strange usage which none of my dictionaries could decipher.
腰を仲ばし、両手を大きく振りながら、てくてく歩く。
While googling I found the sentence 手を前方に進め上体を倒しながら仲ばします accompanied by a picture of someone doing stretching exercises.
From what I know ば is a particle used for conditions but I don't know how 仲 comes into the picture.