Low Back Ache

My back is sore and aching for the past week.  I think it is the hotel beds that cause this problem.  My kidney is weak as the Chinese Sinseh will say.  I had a cold spray and it works but only temporary relief.  I am now doing the "superman" exercise.  This is lying flat on my stomach and arching my back to strengthen my core muscles.  This is my recommendation to friends who suffers from low back pain.  It is the easiest and best way in my opinion to help relieve backache.