title: Stress responses to short-term intensified and reduced training in competitive weightlifters.
abstract: We sought to identify and evaluate the tolerance to, and consequences of, short-term variations in training load in competitive weightlifters. Seven international-level lifters performed 1 week of initial training followed by 2 weeks of intensified (INT: +100%, 36.5 ± 11.3 × 10(3)  kg/week) and 1 week of subsequently reduced (RED: -25%) training within their annual program. After INT, but not RED, 90 min of weightlifting increased mRNA levels of chemokine (C-C motif) ligand 4 (CCL4), chemokine (C-X-C motif) receptor 4 (CXCR4) and cellular stress-associated DNA-damage-inducible transcript 4 (DDIT4) in peripheral blood mononuclear cells by 40-240%. Resting- and weightlifting-induced changes in plasma protein carbonyls, indicative of oxidative stress, but not pro-inflammatory CCL4 concentrations differed between INT and RED. Symptoms of stress (Daily Analysis of Life Demands of Athletes questionnaire) were reported as worse than normal more frequently during INT and RED than initial training. Global (negative) mood state increased during INT and declined during RED. Maximal snatch (-4.3 ± 3.7%) and vertical jump (-7.2 ± 6.5%), but not clean and jerk, were reduced after INT and restored after RED. Chemokine signaling may thus be part of the stress response to intense weightlifting and short-term reductions in training load support recovery from periodic INT training in weightlifters.
authors: Department of Sport and Exercise Science, The University of Auckland, Auckland, New Zealand.
authors: A G
authors: AG
authors: Storey
authors: School of Biological Sciences, Centre for Brain Research and Brain Research New Zealand, The University of Auckland, Auckland, New Zealand.
authors: N P
authors: NP
authors: Birch
authors: Bioinformatics Institute, The University of Auckland, Auckland, New Zealand.
authors: V
authors: V
authors: Fan
authors: Department of Sport and Exercise Science, The University of Auckland, Auckland, New Zealand.
authors: H K
authors: HK
authors: Smith
mesh_terms: D054874:Athletic Performance / Q000502:physiology* / Q000523:psychology; D015415:Biomarkers / Q000097:blood; D018925:Chemokines / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D046228:Microarray Analysis; D010807:Physical Endurance / Q000276:immunology*; D019707:Receptors, Chemokine / Q000097:blood*; D013312:Stress, Physiological / Q000276:immunology*; D013315:Stress, Psychological / Q000209:etiology* / Q000276:immunology; D013997:Time Factors; D014891:Weight Lifting / Q000502:physiology* / Q000523:psychology
chemical_list: D015415:Biomarkers; D018925:Chemokines; D019707:Receptors, Chemokine
keywords: Snatch; cDNA microarray; clean and jerk; gene expression; overload; peripheral blood mononuclear cells; psychologic status; recovery