title: Resting extracellular signal-regulated protein kinase 1/2 expression following a continuum of chronic resistance exercise training paradigms.
abstract: Extracellular signal-regulated protein kinase 1/2 (ERK1/2) moderates skeletal muscle growth; however, chronic responses of this protein to unique resistance exercise (RE) paradigms are yet to be explored. The purpose of this investigation was to describe the long-term response of ERK1/2 following circuit weight training (CWT), recreationally weight training (WT), powerlifting (PL) and weightlifting (WL). Independent t-tests were used to determine differences in trained groups compared to sedentary controls. Total ERK1/2 content was lower in PL and WL compared to their controls (p ≤ 0.05). Specific trained groups displayed large (WL: pERK/total-ERK; d = 1.25) and moderate (CWT: total ERK1/2; d = 0.54) effect sizes for altered kinase expression compared to controls. The results indicate ERK1/2 expression is down-regulated after chronic RE in well-trained weightlifters and powerlifters. Lower expression of this protein may be a method in which anabolism is tightly regulated after many years of high-intensity RE.
authors.affiliation: a Center for Sport Performance, Department of Kinesiology , California State University, Fullerton , Fullerton , CA , USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Galpin
authors.affiliation: b Department of Health, Sport, and Exercise Sciences , University of Kansas , Lawrence , KS , USA.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Fry
authors.affiliation: b Department of Health, Sport, and Exercise Sciences , University of Kansas , Lawrence , KS , USA.
authors.forename: Justin X
authors.initials: JX
authors.lastname: Nicoll
authors.affiliation: c Human Performance Laboratories, Department of Exercise and Sport Sciences , University of Memphis , Memphis , TN , USA.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Moore
authors.affiliation: c Human Performance Laboratories, Department of Exercise and Sport Sciences , University of Memphis , Memphis , TN , USA.
authors.forename: Brian K
authors.initials: BK
authors.lastname: Schilling
authors.affiliation: d Department of Physiology and Biophysics , University of Tennessee-Memphis , Memphis , TN , USA.
authors.forename: Donald B
authors.initials: DB
authors.lastname: Thomason
mesh_terms: D000328:Adult; D001706:Biopsy; D065327:Circuit-Based Exercise; D015536:Down-Regulation; D006801:Humans; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D064797:Physical Conditioning, Human / Q000379:methods* / Q000502:physiology*; D052097:Quadriceps Muscle / Q000378:metabolism* / Q000473:pathology*; D055070:Resistance Training; D014891:Weight Lifting / Q000502:physiology; D055815:Young Adult
chemical_list: D019950:Mitogen-Activated Protein Kinase 1
keywords: MAPK; Skeletal muscle; circuit training; powerlifting; weightlifting