if you film from the front you will see if your knees cave in or not easier. From the sides you see if your hips shoot up first and if you let your chest cave. there’s no wrong answer. Film from any angle if you look solid switch angles. Maybe a diagonal would allow to kind of meld both attributes.
I like a mostly side but slightly diagonal to kind of get a wide angle perspective on things. Also consider your zoom. Don’t zoom in too far cause you might miss what’s going on with your feet but don’t go too wide to show off your Chuck Vogelpohl poster in the background.
Hope this helps.