title: Bicycle riding has no important impact on total and free prostate-specific antigen serum levels in older men.
abstract: OBJECTIVE
  To investigate whether bicycle riding significantly alters total prostate-specific antigen (tPSA), free PSA (fPSA), and percent free PSA (%fPSA) serum concentrations in potential candidates for prostate cancer screening.
  
  
  METHODS
  Thirty-three men, ranging in age from 50 to 74 years (mean 61 +/- 8), rode a 13-mile bicycle course. Blood samples for PSA analysis were drawn immediately before and 1 hour after cycling for 90 minutes. The precycling and postcycling tPSA, fPSA, and %fPSA values were compared using the Wilcoxon matched-pairs test, with P = 0.01 set as the significance level.
  
  
  RESULTS
  Changes between precycling and postcycling values for tPSA (P = 0.517), fPSA (P = 0.048), and %fPSA (P = 0.166) were not statistically significant.
  
  
  CONCLUSIONS
  Physical activity combined with perineal pressure as induced by a 13-mile bicycle tour has no diagnostic impact on PSA values.
authors.affiliation: Department of Urology, University of Essen, Essen, Germany.
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Luboldt
authors.forename: Klaus D
authors.initials: KD
authors.lastname: Peck
authors.forename: Frank
authors.initials: F
authors.lastname: Oberpenning
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Schmid
authors.forename: Axel
authors.initials: A
authors.lastname: Semjonow
mesh_terms: D000368:Aged; D001642:Bicycling; D015992:Body Mass Index; D006801:Humans; D008297:Male; D008875:Middle Aged; D010502:Perineum / Q000033:anatomy & histology; D011312:Pressure / Q000009:adverse effects; D011467:Prostate / Q000033:anatomy & histology; D017430:Prostate-Specific Antigen / Q000097:blood*
chemical_list: D017430:Prostate-Specific Antigen