title: Short-term intense exercise training reduces stress markers and alters the transcriptional response to exercise in skeletal muscle.
abstract: The purpose of this investigation was to examine the influence of short-term intense endurance training on cycling performance, along with the acute and chronic signaling responses of skeletal muscle stress and stability markers. Ten recreationally active subjects (25 ± 2 yr, 79 ± 3 kg, 47 ± 2 ml·kg-1·min-1) were studied before and after a 12-day cycling protocol to examine the effects of short-term intense (70-100% V̇o2max) exercise training on resting and exercise-induced regulation of molecular factors related to skeletal muscle cellular stress and protein stability. Skeletal muscle biopsies were taken at rest and 3 h following a 20-km cycle time trial ondays 1and12to measure mRNA expression and protein content. Training improved (P< 0.05) cycling performance by 5 ± 1%. Protein oxidation was unaltered onday 12, while resting SAPK/JNK phosphorylation was reduced (P< 0.05), suggesting a reduction in cellular stress. The maintenance in the myocellular environment may be due to synthesis of cytoprotective markers, along with enhanced degradation of damage proteins, as training tended (P< 0.10) to increase resting protein content of manganese superoxide dismutase and heat shock protein 70 (HSP70), while mRNA expression of MuRF-1 was elevated (P< 0.05). Following training (day 12), the acute exercise-induced transcriptional response of TNF-α, NF-κB, MuRF-1, and PGC1α was attenuated (P< 0.05) compared withday 1Collectively, these data suggest that short-term intense training enhances protein stability, creating a cellular environment capable of resistance to exercise-induced stress, which may be favorable for adaptation.
authors.affiliation: Human Performance Laboratory, Ball State University, Muncie, Indiana.
authors.forename: J Matthew
authors.identifier: 0000-0002-1341-0725
authors.initials: JM
authors.lastname: Hinkley
authors.affiliation: Human Performance Laboratory, Ball State University, Muncie, Indiana.
authors.forename: Adam R
authors.initials: AR
authors.lastname: Konopka
authors.affiliation: Human Performance Laboratory, Ball State University, Muncie, Indiana.
authors.forename: Miranda K
authors.initials: MK
authors.lastname: Suer
authors.affiliation: Human Performance Laboratory, Ball State University, Muncie, Indiana mharber@bsu.edu.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Harber
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D015444:Exercise / Q000502:physiology*; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology; D000072696:High-Intensity Interval Training / Q000379:methods; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D008297:Male; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000166:cytology / Q000502:physiology*; D018384:Oxidative Stress / Q000502:physiology; D064797:Physical Conditioning, Human / Q000379:methods; D010807:Physical Endurance / Q000502:physiology*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015533:Transcriptional Activation / Q000502:physiology; D059467:Transcriptome / Q000502:physiology*
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D009124:Muscle Proteins; D017382:Reactive Oxygen Species
keywords: MuRF-1; SAPK/JNK; myostatin; proliferator-activated receptor gamma coactivator 1-α; protein oxidation