title: β-Hydroxy-β-methylbutyrate (HMB)-free acid attenuates circulating TNF-α and TNFR1 expression postresistance exercise.
abstract: The purpose of this study was to examine the effect of β-hydroxy-β-methylbutyrate-free acid (HMB-FA) and cold-water immersion (CWI) on circulating concentrations of TNF-α and monocyte TNF-α receptor 1 (TNFR1) expression. Forty resistance-trained men (22.3 ± 2.4 yr) were randomized into four groups [placebo (PL), HMB-FA, CWI, and HMB-FA-CWI] and performed an acute, intense exercise protocol (four sets of up to 10 repetitions of the squat, dead lift, and split squat). Participants also performed four sets of up to 10 repetitions of the squat at 24 and 48 h following the initial exercise bout. Blood was sampled before exercise (PRE), immediately postexercise (IP), and 30 min, 24 h, and 48 h postexercise (30P, 24P, and 48P, respectively). Circulating TNF-α was assayed, and TNFR1 expression on CD14+ monocytes was measured by flow cytometry. The exercise protocol significantly elevated TNF-α in only PL (P = 0.006) and CWI (P = 0.045) IP. Mean percent changes show that TNF-α significantly increased from PRE to IP for only PL and CWI groups (P < 0.05), whereas the percent change of TNF-α for HMB-FA and HMB-FA-CWI was not significant. TNFR1 expression was elevated in PL (P = 0.023) and CWI (P = 0.02) at 30P compared with PRE, whereas both HMB-FA-treated groups did not increase significantly. In conclusion, HMB-FA attenuated circulating TNF-α IP and TNFR1 expression during recovery compared with PL and CWI. HMB-FA supplementation may attenuate the initial immune response to intense exercise, which may reduce recovery time following intense exercise.
authors.affiliation: Institute of Exercise Science and Wellness, Sport and Exercise Science, University of Central Florida, Orlando, Florida.
authors.forename: Jeremy R
authors.initials: JR
authors.lastname: Townsend
authors.forename: Maren S
authors.initials: MS
authors.lastname: Fragala
authors.forename: Adam R
authors.initials: AR
authors.lastname: Jajtner
authors.forename: Adam M
authors.initials: AM
authors.lastname: Gonzalez
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Wells
authors.forename: Gerald T
authors.initials: GT
authors.lastname: Mangine
authors.forename: Edward H
authors.initials: EH
authors.lastname: Robinson
authors.forename: William P
authors.initials: WP
authors.lastname: McCormack
authors.forename: Kyle S
authors.initials: KS
authors.lastname: Beyer
authors.forename: Gabriel J
authors.initials: GJ
authors.lastname: Pruna
authors.forename: Carleigh H
authors.initials: CH
authors.lastname: Boone
authors.forename: Tyler M
authors.initials: TM
authors.lastname: Scanlon
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Bohner
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Stout
authors.forename: Jay R
authors.initials: JR
authors.lastname: Hoffman
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D003080:Cold Temperature; D019587:Dietary Supplements; D004311:Double-Blind Method; D015536:Down-Regulation; D006801:Humans; D007101:Immersion; D018836:Inflammation Mediators / Q000097:blood*; D018950:Lipopolysaccharide Receptors / Q000097:blood; D008297:Male; D009000:Monocytes / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000097:blood*; D020127:Recovery of Function; D055070:Resistance Training; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood*; D014631:Valerates / Q000008:administration & dosage*; D014867:Water; D055815:Young Adult
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D018950:Lipopolysaccharide Receptors; D047888:Receptors, Tumor Necrosis Factor, Type I; C506235:TNFRSF1A protein, human; D014409:Tumor Necrosis Factor-alpha; D014631:Valerates; D014867:Water; C004961:beta-hydroxyisovaleric acid
keywords: immune function; muscle damage; protein; recovery; supplement