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RESEARCH PRODUCT
Vitamin C and E supplementation alters protein signalling after a strength training session, but not muscle growth during 10 weeks of training
Håvard WiigElisabet BørsheimElisabet BørsheimJuha J. HulmiIna GartheKristoffer Toldnes CummingHåvard HamarslandR. E. JohansenGøran PaulsenTruls Raastadsubject
AdultMalemedicine.medical_specialtyJournal ClubPhysiologyStrength trainingMAP Kinase Signaling Systemmedicine.medical_treatmentMolecular and CellularMuscle ProteinsIsometric exerciseAscorbic AcidBiologyp38 Mitogen-Activated Protein KinasesMuscle hypertrophyIsometric ContractionInternal medicinemedicineHumansVitamin Eta315Leg pressMuscle SkeletalMitogen-Activated Protein Kinase 1Mitogen-Activated Protein Kinase 3Vitamin Cta1184Vitamin EBiceps curlRibosomal Protein S6 Kinases 70-kDaResistance TrainingVitaminsAscorbic acidAdaptation PhysiologicalEndocrinologyDietary SupplementsFemaledescription
This study investigated the effects of vitamin C and E supplementation on acute responses and adaptations to strength training. Thirty-two recreationally strength-trained men and women were randomly allocated to receive a vitamin C and E supplement (1000 mg day(-1) and 235 mg day(-1), respectively), or a placebo, for 10 weeks. During this period the participants' training involved heavy-load resistance exercise four times per week. Muscle biopsies from m. vastus lateralis were collected, and 1 repetition maximum (1RM) and maximal isometric voluntary contraction force, body composition (dual-energy X-ray absorptiometry), and muscle cross-sectional area (magnetic resonance imaging) were measured before and after the intervention. Furthermore, the cellular responses to a single exercise session were assessed midway in the training period by measurements of muscle protein fractional synthetic rate and phosphorylation of several hypertrophic signalling proteins. Muscle biopsies were obtained from m. vastus lateralis twice before, and 100 and 150 min after, the exercise session (4 × 8RM, leg press and knee-extension). The supplementation did not affect the increase in muscle mass or the acute change in protein synthesis, but it hampered certain strength increases (biceps curl). Moreover, increased phosphorylation of p38 mitogen-activated protein kinase, Extracellular signal-regulated protein kinases 1 and 2 and p70S6 kinase after the exercise session was blunted by vitamin C and E supplementation. The total ubiquitination levels after the exercise session, however, were lower with vitamin C and E than placebo. We concluded that vitamin C and E supplementation interfered with the acute cellular response to heavy-load resistance exercise and demonstrated tentative long-term negative effects on adaptation to strength training.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2014-12-15 |