Best recommendation for spinal stenosis is a structured exercise program with an experienced PT. PT will help you target the muscles that have weakened and instruct in specific exercises that can be strengthened. Core exercises in particular are recommended to help spinal stenosis symptoms. Once you complete a PT exercise program you will have to continue with those exercises for life to maintain the gains. Swimming is also a great core workout as the gravity free water environment supports body weight, reduces spinal pressure and strengthens muscles. It takes time and perseverance to overcome back pain such as yours. Your doctor should be able to recommend an experienced PT and provide a prescription with recommendations. Good luck!