Lumbar strain is an injury to the muscles or ligaments in the lower back, often caused by lifting heavy objects, sudden movements, or poor posture. Symptoms typically include pain, stiffness, and limited mobility in the lower back area. Treatment for lumbar strain usually involves rest, ice application, and over-the-counter pain relievers. In some cases, physical therapy may be recommended to strengthen the back muscles and improve flexibility. Preventive measures include maintaining proper posture and using correct lifting techniques to avoid future injuries.