Abstract
Using non-invasive procedures the authors tried to determine exercise-induced changes in LDH (EC 1. 1. 1. 27) activities and LDH isozymes in the tissues and blood of marathon runners by urine assay. Urine samples obtained from 5 well-trained male volunteers ranging in age from 22 to 57 were collected before running and at 0, 1/2, 1 and 2hr after completion of a marathon. Urine LDH activity was determined. LDH isozymes were separated by agarose electrophoresis, and the portion of LDH-H activity and percent of LDH-H/LDH were estimated. Immediately after the marathon, total LDH activity was significantly (p<0.001) elevated from 2.23±1.45 to 9.89±5.90μ moles· min-1· per gram of creatinine (X±SD), while the percent of LDH-H/LDH significantly (p<0.001) decreased from 95.50±8.99 to 74.95±11.38% (X±SD) . These values returned to the baseline level within 2hr.
