Soreness on the outside of the calf by pressing a line may be caused by chronic strain injury, lumbar disc herniation, spondylitis and other reasons. 1. Chronic strain injury: long-term, massive, high-intensity exercise calf, such as stretching, marathon, etc., can cause chronic strain injury of calf muscles, ligaments, joint capsules and other soft tissues, congestion, edema and other phenomena. And can lead to the accumulation of acidic products, pain, swelling, soreness, fatigue and other symptoms. 2. Lumbar disc herniation: the prolapsed lumbar disc can cause compression and/or irritation of the nerve root, resulting in radiating pain, numbness and other sensory abnormalities in one or both lower limbs, as well as movement abnormalities such as heaviness and weakness. 3. Myelitis: When the spinal cord is invaded by bacteria, viruses, fungi, parasites, etc., or due to autoimmune factors, resulting in inflammatory reactions such as congestion and edema of the spinal cord, it can cause peripheral nerve sensory and motor abnormalities, such as soreness in a line on the lateral side of the calf. There are many other causes of lateral calf pain, we recommend that you consult a doctor for a clear diagnosis and targeted treatment under the guidance of the doctor.