An axial load on the spine in flexion or extension can cause simultaneous compression and tension in a spinal disc.

“now let's talk about load in the context of flinch F flexion and extension where you now do have within the disc it's not just pure compression it's actually again if you're in so maybe just even explain to people flexion is bending forward extension is going back so um now if you have an axial load in that position which you could easily have if you're deadlifting something or squatting something any given disc in that especially in that lower spine region can be under compression and tension at the same time correct”