When running you almost never want to mess with your chest.
It throws your Tori into actual rotation, unlike when you move your pecs and it just acts like a counter balance for your step.
An exception to this could be relaxing it and holding one pec to center your chest again, since your chest will slowly rotate as you run, due to the hold state not being that strong.
Try not to see running as one step after the other, there's gonna be times in every replay where you may have to just hold your legs in order to tip over a bit more before taking the next step.
Avoid stressing moves in parkour, take your time to set it all up correctly.

Your moves are really fluid but I feel like you could spend more time on your dm's.
Perhaps try getting the hits symmetric or just bigger in general? Especially the first one where you wouldn't lose a lot by going back and editing :3
Don't get me wrong though, your replay looks great ,_,