title: Detraining produces minimal changes in physical performance and hormonal variables in recreationally strength-trained men.
abstract: The object of this study was to examine changes in muscular strength, power, and resting hormonal concentrations during 6 weeks of detraining (DTR) in recreationally strength-trained men. Each subject was randomly assigned to either a DTR (n = 9) or resistance training (RT; n = 7) group after being matched for strength, body size, and training experience. Muscular strength and power testing, anthropometry, and blood sampling were performed before the experimental period (T1), after 3 weeks (T2), and after the 6-week experimental period (T3). One-repetition maximum (1RM) shoulder and bench press increased in RT at T3 (p </= 0.05), whereas no significant changes were observed in DTR. Peak power output and mean power output significantly decreased (9 and 10%) in DTR at T2. Peak torque of the elbow flexors at 90 degrees did not change in the RT group but did significantly decrease by 11.9% at T3 compared with T1 in the DTR group. Vertical jump height increased in RT at T2 but did not change in DTR. Neither group displayed any changes in 1RM squat, body mass, percent body fat, or resting concentrations of growth hormone, follicle-stimulating hormone, luteinizing hormone, sex hormone-binding globulin, testosterone, cortisol, or adrenocorticotropin. These data demonstrate that 6 weeks of resistance DTR in recreationally trained men affects power more than it does strength without any accompanying changes in resting hormonal concentrations. For the recreational weight trainer, losses in strength over 6 weeks are less of a concern compared with anaerobic power and upper arm isometric force production. Anaerobic power exercise with a high metabolic component coming from glycolysis might be of importance for reducing the impact of DTR on Wingate power performances. A minimal maintenance training program is recommended for the recreational lifter to offset any reductions in performance.
authors.affiliation: The Human Performance Laboratory, Department of Kinesiology Unit 1110, The University of Connecticut, Storrs 06269, USA. kraemer@uconnvm.uconn.edu
authors.forename: William J
authors.initials: WJ
authors.lastname: Kraemer
authors.forename: L Perry
authors.initials: LP
authors.lastname: Koziris
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Ratamess
authors.forename: Keijo
authors.initials: K
authors.lastname: Hakkinen
authors.forename: N Travis
authors.initials: NT
authors.lastname: TRIPLETT-McBRIDE
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Fry
authors.forename: Scott E
authors.initials: SE
authors.lastname: Gordon
authors.forename: Jeff S
authors.initials: JS
authors.lastname: Volek
authors.forename: Duncan N
authors.initials: DN
authors.lastname: French
authors.forename: Martyn R
authors.initials: MR
authors.lastname: Rubin
authors.forename: Ana L
authors.initials: AL
authors.lastname: Gomez
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Sharman
authors.forename: J
authors.initials: J
authors.lastname: Michael Lynch
authors.forename: Mikel
authors.initials: M
authors.lastname: Izquierdo
authors.forename: Robert U
authors.initials: RU
authors.lastname: Newton
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Fleck
mesh_terms: D000328:Adult; D000693:Anaerobiosis; D000886:Anthropometry; D006728:Hormones / Q000097:blood*; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D010809:Physical Fitness; D014891:Weight Lifting / Q000502:physiology*
chemical_list: D006728:Hormones