In sexual life, other environments are likely to be the above two situations, plus strain, because in most environments, erector spinae is isometric contraction and barks almost all day. If there is no stretching and training at ordinary times, the muscles will form high tension, that is, when you don't need it, the muscles will still work at high intensity. At this time, if the muscle itself is slightly damaged, it doesn't matter, but in high-intensity contraction, the speed of self-healing of this injury will be very slow, and new injuries will appear before self-healing. I suggest stretching erector spinae more and changing positions.