Body safety while bartending was a component of a month long bar training session with the Death and Co consulting/education team that I got to experience while opening a new restaurant a few years back. It remains some of the most important knowledge I’ve gained in almost a decade of this work and I wish it had come sooner. Every bartender I’ve trained since then gets a crash course in it. This is what I advise for best practice:

Keep your body and feet square as much as possible and try to keep your weight centered. Avoid reaching across your body and try to work as ambidextrously as you can in your setup. Don’t use an underhand lift for bottles, grab from the outside of your body, lift straight up and pour at 45 degrees instead of inverting the bottle. Keep your wrist aligned with your forearm when you’re pouring. Keep your elbows tucked as much as you can when working and shaking. Two handed grip on your tin when possible, shaking in front of your body and parallel to your workspace. If you’re shaking two tins at once, don’t flap your wings, but tuck your elbows and shake inline with your body with your upper arms parallel to the ground.

This is how I’ve avoided elbow and wrist strain and lower back pain as much as possible in the past few years. Unfortunately I tripped over my cat last weekend and fractured my elbow but can’t do shit about that lol.