The carioca exercise has great value for mobility of the upper back because it combines a twist on both the pelvis and the shoulders.While the the shoulder rotates medially, the opposite knee with pelvis turn the other direction. The first question is that safe to the lumbar spine? Yes because the torque isn’t very high since the lower body motions are firm but not excessive and most of the motion comes from the shoulders. The velocities of the exercise are not dangerous, but most of the time the arms are moving side to side without rotation so you have to coach it to get the changes you need. Most of the time people go through the motions of drills and it’s up to the coach to explain the value of them.