I'm 5'4'' and I have to sit on a pillow in order to have the massager massage my shoulders and back correctly. My fiancee is 5'7'' and it massage his head instead. I think you have to be at least 5'8'' in order for it to massage your shoulders unless you sit on top of a pillow. The heated part, I only can feel it on my legs. Not warm enough! it should have it heated on the back and level of adjustment of how warm you want it. The massage is poorly made and does not massage correctly!