We have established an outpatient clinic specializing in anemia (Takemoto, 2017; Takemoto, 2019) to comprehensively assess the clinical laboratory data on anemia, including serum levels of haptoglobin, creatine kinase, folate, and vitamin B12 in addition to hemoglobin (Hb) and ferritin as a fundamental assessment for the athletes. This evidence concerns the gene GSTM1 and anemia (phenotype).