title: Androgen receptor content following heavy resistance exercise in men.
abstract: The purpose of the present investigation was to examine androgen receptor (AR) content in the vastus lateralis following two resistance exercise protocols of different volume. Nine resistance-trained men (age=24.3+/-4.4 years) performed the squat exercise for 1 (SS) and 6 sets (MS) of 10 repetitions in a random, counter-balanced order. Muscle biopsies were performed at baseline, and 1h following each protocol. Blood was collected prior to, immediately following (IP), and every 15 min after each protocol for 1h. No acute elevations in serum total testosterone were observed following SS, whereas significant 16-23% elevations were observed at IP, 15, and 30 min post-exercise following MS. No acute elevations in plasma cortisol were observed following SS, whereas significant 31-49% elevations were observed for MS at IP, 15, and 30 min post-exercise. Androgen receptor content did not change 1h following SS but significantly decreased by 46% following MS. These results demonstrated that a higher volume of resistance exercise resulted in down-regulation of AR content 1h post-exercise. This may have been due to greater protein catabolism associated with the higher level of stress following higher-volume resistance exercise.
authors.affiliation: Human Performance Laboratory, Department of Kinesiology, Unit 1110, University of Connecticut, Storrs, CT 06269-1110, USA.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Ratamess
authors.forename: William J
authors.initials: WJ
authors.lastname: Kraemer
authors.forename: Jeff S
authors.initials: JS
authors.lastname: Volek
authors.forename: Carl M
authors.initials: CM
authors.lastname: Maresh
authors.forename: Jaci L
authors.initials: JL
authors.lastname: Vanheest
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Sharman
authors.forename: Martyn R
authors.initials: MR
authors.lastname: Rubin
authors.forename: Duncan N
authors.initials: DN
authors.lastname: French
authors.forename: Jason D
authors.initials: JD
authors.lastname: Vescovi
authors.forename: Ricardo
authors.initials: R
authors.lastname: Silvestre
authors.forename: Disa L
authors.initials: DL
authors.lastname: Hatfield
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Fleck
authors.forename: Michael R
authors.initials: MR
authors.lastname: Deschenes
mesh_terms: D000328:Adult; D000728:Androgens / Q000097:blood; D001706:Biopsy; D015153:Blotting, Western; D001823:Body Composition; D015930:Diet Records; D004797:Enzyme-Linked Immunosorbent Assay; D015444:Exercise; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000378:metabolism; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism*; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013739:Testosterone / Q000097:blood; D013997:Time Factors; D014891:Weight Lifting
chemical_list: D000728:Androgens; D011944:Receptors, Androgen; D012738:Sex Hormone-Binding Globulin; D019344:Lactic Acid; D013739:Testosterone; D006854:Hydrocortisone