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PubMed · 15329060

Muscular adaptations to computer-guided strength training with eccentric overload.

B Friedmann·R Kinscherf·S Vorwald·H Müller·K Kucera·S Borisch·G Richter·P Bärtsch·R Billeter
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Abstract

AIMS: In order to investigate the muscular adaptations to a novel form of strength training, 18 male untrained subjects performed 4 weeks of low resistance-high repetition knee extension exercise. METHODS: Nine of them trained on a conventional weight resistance device (Leg curler, CON/ECC group), with loads equivalent to 30% of the concentric one-repetition maximum (1RM) for both the concentric and eccentric phase of movement. The other nine trained on a newly developed computer-driven device (CON/ECC-OVERLOAD group) with the concentric load equivalent to 30% of the concentric 1RM and the eccentric load equivalent to 30% of the eccentric 1RM. RESULTS: Training resulted in significantly (P < or = 0.05) increased peak torque and a tendency (P=0.092) to increased muscle cross-sectional area for the CON/ECC-OVERLOAD but not the CON/ECC group, while strength endurance capacity was significantly (P < or = 0.05) increased in the CON/ECC group only. RT-PCR revealed significantly increased myosin heavy chain (MHC) IIa and lactate dehydrogenase (LDH) A mRNAs, a tendency for increased MHC IIx mRNA (P = 0.056) and high correlations between the changes in MHC IIx and LDH A mRNAs (r=0.97, P=0.001) in the CON/ECC-OVERLOAD group. CONCLUSIONS: These results indicate a shift towards a more type II dominated gene expression pattern in the vasti laterales muscles of the CON/ECC-OVERLOAD group in response to training. We suggest that the increased eccentric load in the CON/ECC-OVERLOAD training leads to distinct adaptations towards a stronger, faster muscle.

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Adaptation, PhysiologicalExerciseHumansIsoenzymesL-Lactate DehydrogenaseLactate Dehydrogenase 5LegMaleMicrocomputersMuscle Fibers, SkeletalMuscle, SkeletalMyosin Heavy ChainsMyosin Type IPhosphofructokinasesPhysical EnduranceRNA, MessengerReverse Transcriptase Polymerase Chain ReactionSkeletal Muscle MyosinsJournal ArticleResearch Support, Non-U.S. Gov't

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B Friedmann, R Kinscherf, S Vorwald, H Müller, K Kucera, S Borisch, G Richter, P Bärtsch, R Billeter. 2004. Muscular adaptations to computer-guided strength training with eccentric overload.. https://doi.org/10.1111/j.1365-201x.2004.01337.x

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