Home Health-Fitness Just Do It: 5 Moves to Strengthen Your Back – The best exercises build both sets of muscles that support the spine — large, superficial muscles and inner support ones. The exercises below, vetted by Sheila A. Dugan, MD, and Chicago physical therapist Vonna Karoghlanian, build both groups. Do them twice a day. (Always check with your doctor before beginning this or any other new exercise program.)