Muscular adaptations to computer-guided strength training with eccentric overload

Acta Physiol Scand. 2004 Sep;182(1):77-88. doi: 10.1111/j.1365-201X.2004.01337.x.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological
  • Exercise / physiology*
  • Humans
  • Isoenzymes / analysis
  • L-Lactate Dehydrogenase / analysis
  • Lactate Dehydrogenase 5
  • Leg
  • Male
  • Microcomputers
  • Muscle Fibers, Skeletal / physiology
  • Muscle, Skeletal / anatomy & histology
  • Muscle, Skeletal / physiology*
  • Myosin Heavy Chains / analysis
  • Myosin Type I / analysis
  • Phosphofructokinases / analysis
  • Physical Endurance / physiology
  • RNA, Messenger / analysis
  • Reverse Transcriptase Polymerase Chain Reaction / methods
  • Skeletal Muscle Myosins / analysis


  • Isoenzymes
  • RNA, Messenger
  • L-Lactate Dehydrogenase
  • Lactate Dehydrogenase 5
  • lactate dehydrogenase 1
  • Phosphofructokinases
  • Myosin Type I
  • Skeletal Muscle Myosins
  • Myosin Heavy Chains