A randomized pilot study of monthly cycled testosterone replacement or continuous
testosterone replacement versus placebo in older men.
Author(s): Sheffield-Moore M, Dillon EL, Casperson SL, Gilkison CR, Paddon-Jones D, Durham
WJ, Grady JJ, Urban RJ.
Affiliation(s): Department of Internal Medicine, The University of Texas Medical Branch at
Galveston, Texas 77555, USA.
Publication date & source: 2011, J Clin Endocrinol Metab. , 96(11):E1831-7
CONTEXT: Cycling androgens has been reported by athletes to improve physical
performance by enhancing muscle mass and strength, a paradigm that has not been
studied, and may have clinical value in older men being treated with
testosterone.
OBJECTIVE: We investigated the efficacy of a monthly cycled testosterone regimen
that uses half the testosterone dose as the current standard of care continuous
therapy on body composition and muscle strength in older men.
DESIGN, SETTING, AND PATIENTS: Twenty-four community-dwelling older men 70 ± 2 yr
of age with total testosterone levels below 500 ng/dl were randomized at the
Institute for Translational Sciences-Clinical Research Center into a 5-month
double-blind placebo-controlled trial.
INTERVENTION: Subjects were dosed weekly for 5 months, receiving continuous
testosterone (TE, n = 8; 100 mg testosterone enanthate, im injection), monthly
cycled testosterone (MO, n = 8; alternating months of testosterone and placebo),
or placebo (PL, n = 8).
MAIN OUTCOME MEASURES: Main outcomes included body composition by dual-energy
x-ray absorptiometry and upper and lower body muscle strength. Secondary outcomes
included body weight, serum hormones, and mixed-muscle protein fractional
synthesis rate (FSR).
RESULTS: Total lean body mass was increased and percent fat was reduced after 5
months in TE and MO (P < 0.05). Upper body muscle strength increased in TE, and
lower body muscle strength increased in TE and MO (P < 0.05). FSR increased in TE
and MO (P < 0.05) but not in PL.
CONCLUSIONS: Cycled testosterone improved body composition and increased muscle
strength compared with placebo and increased FSR similarly to continuous
testosterone.
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