Rolling abdominal waist acid to consider with excessive exercise, lumbar muscle strain, lumbar spine disease and so on. 1. Exercise excess: usually exercise less, if suddenly do curling exercise or exercise time is longer, can cause lumbar muscle lactic acid metabolite increase, thereby stimulating the nerve resulting in lumbar acid. 2. Lumbar muscle strain: curling exercise is strenuous or incorrect movement, may lead to lumbar muscle strain, causing lumbar aseptic inflammation, resulting in lumbar acidity. 3. Lumbar spine disease: if you suffer from lumbar disc herniation, spinal stenosis, do curling exercise will lead to the original lumbar spine disease aggravation, thus compression of the nerve root leading to lumbar pain. Curl waist acid may also be related to other causes, should promptly consult a doctor to clarify the cause of waist acid, and standardized treatment under the guidance of the doctor.