Whether high creatinine is normal in people who work out for a long time needs to be analyzed on a case-by-case basis. Creatinine is a metabolic product of muscle in the body, which is mainly excreted by the kidneys. Serum creatinine is relatively stable in the body, and the measurement of creatinine value can reflect the glomerular filtration function; urine creatinine mainly comes from the part of blood that is excreted with urine after glomerular filtration, and also has a certain role in responding to kidney function. 1, normal: creatinine is a creatine metabolite, fitness can strengthen muscle metabolism, resulting in a mild increase in creatinine, this creatinine increase is physiological and belongs to the normal situation, do not worry too much; In addition, a large intake of meat and protein can also lead to a physiological increase in creatinine, which can generally return to normal after 12 hours; 2, abnormal: when pathological changes occur in the kidneys, creatinine can also be seen to rise, which is common in glomerulonephritis, nephrotic syndrome, chronic renal failure, late diabetes and other diseases, which is an abnormal situation. Patients with kidney disease are often accompanied by changes in urinary habits, such as reduced urine volume or even oliguria, as well as hematuria and foamy urine, and some patients also develop edema. The common symptoms of diabetic patients are “three more and one less”, that is, drinking more, eating more, urinating more and losing weight. It is possible to have a mild increase in physiological creatinine with long-term fitness, but it is still recommended to go to the hospital and follow medical advice to improve the relevant tests to exclude pathological causes.