This mobility exercise is awesome for working through tightness in the glute muscle that can contribute to low back and hip issues.
Passive Release: Start by lying on 1 Acumobility ball in the center of the glute which is called the piriformis muscle. Cross the leg over the opposite knee as you do small
Active Release: In the same position, this time work your hip through internal and external rotation as you drive pressure into the piriformis muscle. If there is not a lot of mobility of that hip, continue to do this release regularly looking for the range of motion to increase.