Abstract
Athletes in training have significantly higher levels of serum aldolase activity at
rest when compared to nonathletes. This is due to the higher level (and higher proportion)
of aldolase isoenzyme A, predominant in muscle. At rest, athletes with a history of
infectious hepatitis show significantly higher proportional and absolute levels of
aldolase B, predominant in liver. Long-lasting exercise leads to a rise in serum aldolase
activity, which must be ascribed to the increase in isoenzyme A. Significant post-exercise
changes in isoenzyme ? were not observed. There was no correlation between changes
in serum hemoglobin, as reflecting intravascular hemolysis, and changes in serum aldolase
activity. The data are discussed in regard to the existing hypotheses regarding increases
in serum enzyme activity after physical exercise.
Key words
aldolase isoenzymes - exercise
