Many low back problems seen clinically these days have their origins in the hip – mainly due to long periods sitting which allows the Psoas (main hip flexor) to rest in a shortened position.
As your Psoas gets too used to this position it begins to limit the amount of hip extension you can do – actively take the leg behind your torso.
A tight Psoas also limits how well your glute muscles can work .
With all this in mind its time you stretched those hip flexors properly for once and for all.
Follow the Stretch below and see how well your hips move afterwards