PHYSICAL-ACTIVITY RELEASES PROSTATE-SPECIFIC ANTIGEN (PSA) FROM THE PROSTATE-GLAND INTO BLOOD AND INCREASES SERUM PSA CONCENTRATIONS

Determination of prostate-specific antigen (PSA) is an established too l in detecting prostate cancer. However, the effect of physical activi ty on the PSA concentration in serum is controversial. We measured ser um concentrations of PSA and prostatic acid phosphatase (PAP) in 301 h ealthy outpatients before and after they performed standardized exerci se. Immediately after 15 min of exercise on a bicycle ergometer, their serum PSA concentrations increased by as much as threefold. The incre ase was age dependent and correlated to the PSA concentration before e xercise. This increase was evident in both the free and complexed frac tions of PSA. The amount of PSA secreted into blood depends on the vol ume of the prostate, whereas productivity of the prostate epithelium r emains constant or increases slightly with age, We present cutoff valu es for clinical use. PAP was also increased, but to a lesser extent. T he PSA and PAP secretion mechanisms differ. Our data suggest that exte nsive physical activity should be avoided before blood sampling for di agnostic purposes and, in case of an increase, the PSA concentration s hould be controlled after an exercise test.