title: Resting steroid hormone concentrations in lifetime exercisers and lifetime sedentary males.
abstract: BACKGROUND
  Advancing age in men is associated with a progressive decline in serum testosterone (T) and interactions between exercise, aging and androgen status are poorly understood. The primary aim of this study was to establish the influence of lifelong training history on serum T, cortisol (C) and sex hormone binding globulin (SHBG) in aging men. A secondary aim was to determine the agreement between serum and salivary measurement of steroid hormones in ageing men.
  
  
  METHODS
  Serum and salivary steroid hormones (serum C, T and SHBG, and salivary measures of C and T) were determined and compared between two distinct groups; lifelong exercising males (LE [n = 20], 60.4 ± 4.7 year) and age matched lifelong sedentary individuals (SED [n = 28], 62.5 ± 5.3 years).
  
  
  RESULTS
  T-test revealed a lack of significant differences for serum C or SHBG between LE and SED, while Mann-Whitney U revealed a lack of differences in total T (TT), bioavailable T (bio-T) or free testosterone (free-T). Further, salivary T (sal-T) did not correlate with serum markers of T in LE, SED, or when pooled (r = 0.040; p > 0.05).
  
  
  CONCLUSIONS
  Findings from this investigation suggested that resting levels of serum T and calculated free-T was unable to distinguish between diverse lifelong training histories in aging men. Further, sal-T was not an appropriate indicator of serum T and calculated free-T values in older males and considerable caution should be exercised when interpreting sal-T measurements in aging males.
authors.affiliation: School of Human Sciences, London Metropolitan University , London , UK .
authors.forename: Lawrence D
authors.initials: LD
authors.lastname: Hayes
authors.forename: Nicholas
authors.initials: N
authors.lastname: Sculthorpe
authors.forename: Peter
authors.initials: P
authors.lastname: Herbert
authors.forename: Julien S
authors.initials: JS
authors.lastname: Baker
authors.forename: David A
authors.initials: DA
authors.lastname: Hullin
authors.forename: Liam P
authors.initials: LP
authors.lastname: Kilduff
authors.forename: Fergal M
authors.initials: FM
authors.lastname: Grace
mesh_terms: D000368:Aged; D000375:Aging / Q000097:blood / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D057185:Sedentary Behavior; D012738:Sex Hormone-Binding Globulin / Q000032:analysis*; D013739:Testosterone / Q000097:blood*
chemical_list: D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D006854:Hydrocortisone
keywords: Aging; cortisol; exercise; saliva; sex hormone binding globulin; testosterone