title: Testosterone, dehydroepiandrosterone, and physical performance in older men: results from the Massachusetts Male Aging Study.
abstract: OBJECTIVE
  This manuscript examines the relationships of total testosterone (T), bioavailable T, dehydroepiandrosterone (DHEA), and DHEA sulfate (DHEAS) to measures of physical performance in a large, population-based, random sample of men.
  
  
  METHODS
  In the most recent wave of the Massachusetts Male Aging Study, measures of strength and physical performance [seven-item physical performance test (PPT), timed chair stand test, and grip strength] were made in 684 men, aged 55-85 yr. Complete hormone data were also obtained. Initial graphical exploration of performance outcomes as a function of hormone levels showed linear increases in physical performance up to certain threshold hormone concentrations, beyond which the associations were diminished. Regression models were used to estimate threshold locations and standardized regression coefficients quantifying the association between hormones and strength.
  
  
  RESULTS
  All hormones exhibited significant age-adjusted positive association with PPT score below, but not necessarily above, the thresholds. DHEA was positively associated with chair stand score below, but was not above the threshold. None of the hormones studied was significantly associated with grip strength.
  
  
  CONCLUSIONS
  Up to certain critical concentrations, elevated levels of TT, total T, bioavailable T, DHEA, and DHEA sulfate are associated with increased physical performance, as indicated by the PPT. However, levels beyond those critical concentrations, as might be achieved through exogenous supplementation, do not appear to confer any additional benefit. In general, hormone concentrations do not appear to be meaningfully associated with grip strength or chair stand scores.
authors.affiliation: New England Research Institutes, 9 Galen Street, Watertown, MA 02472, USA.
authors.forename: Amy B
authors.initials: AB
authors.lastname: O'Donnell
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Travison
authors.forename: Susan S
authors.initials: SS
authors.lastname: Harris
authors.forename: J Lisa
authors.initials: JL
authors.lastname: Tenover
authors.forename: John B
authors.initials: JB
authors.lastname: McKinlay
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003687:Dehydroepiandrosterone / Q000097:blood*; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood; D015577:Geriatric Assessment; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010809:Physical Fitness / Q000502:physiology*; D018709:Statistics, Nonparametric; D013739:Testosterone / Q000097:blood*
chemical_list: D013739:Testosterone; D003687:Dehydroepiandrosterone; D019314:Dehydroepiandrosterone Sulfate