2.4. Blood Sampling
IGGT
BLOOD, LIVER
Blood samples were taken twice before and after exercise to analyze the measurement variables. All study participants were asked to fast for at least 10 hr before measurements. Between 8 and 9 AM, 10 mL of blood was collected from the forearm vein. The collected blood was placed in an ethylenediaminetetraacetic acid-treated tube to inhibit coagulation. The serum was then separated by centrifugation at 3,000 rpm for 10 min (Combi-514, Hanil, Korea).Ammonia was analyzed using the NH3L system (Roche, Switzerland), and lactic acid was measured using a Cobas Integra 800 (Roche, Switzerland) biochemical analyzer. Liver function (AST and ALT levels) was analyzed using AST-ALT reagents (Bayer, USA) and an ADVIA 1650 device (Bayer, Japan). IgA, IgG, and IgM levels were analyzed by immunoturbidity measurements using IGGT, IGA, and IGM devices (Roche Diagnostic System, Germany). After mixing each antiserum with serum and incubation at 37°C for 10 min, absorbance was measured at 340 nm (Integra 800, Roche, Switzerland), and the concentration of IgA, IgG, and IgM was determined from the concentration in the standard curve [