Hi! your son is not an overweight patient as his body mass index
is about 20 which is within normal limit , as his liver enzymes were normal so chances of fatty liver disease and intrahepatic/extrahepatic biliary obstruction is almost excluded. Now to rule out exercise induced haemolysis you should repeat his total bilirubin
and simultaneously go for his indirect bilirubin, haemoglobin, MCV, RBC count, reticulocyte
count, platelet count
, serum haptoglobin , serum LDH and urine urobilinogen level. Assessment of these laboratory test will rule out or confirm any ongoing hemolysis. Take care.