Expression of genes related to muscle plasticity after strength and power training regimens

Scand J Med Sci Sports. 2010 Apr;20(2):216-25. doi: 10.1111/j.1600-0838.2009.00905.x. Epub 2009 Apr 14.

Abstract

The purpose of our study was to compare the effects of 8-week progressive strength and power training regimens on strength gains and muscle plasticity [muscle fiber hypertrophy and phenotype shift, mammalian target of rapamycin (mTOR), regulatory-associated protein of mTOR (RAPTOR), rapamycin-insensitive companion of m-TOR (RICTOR), calcineurin and calcipressin gene expression]. Twenty-nine physically active subjects were divided into three groups: strength training (ST), power training (PT) and control (C). Squat 1 RM and muscle biopsies were obtained before and after the training period. Strength increased similarly for both ST and PT groups (P<0.001). Fiber types I, IIa and IIb presented hypertrophy main time effect (P<0.05). Only type IIb percentage decreased from pre- to post-test (main time effect, P<0.05). mTOR and RICTOR mRNA expression increased similarly from pre- to post-test (P<0.01). RAPTOR increased after training for both groups (P<0.0001), but to a greater extent in the ST (P<0.001) than in the PT group. 4EBP-1 decreased after training when the ST and PT groups were pooled (P<0.05). Calcineurin levels did not change after training, while calcipressin increased similarly from pre- to post-test (P<0.01). In conclusion, our data indicate that these training regimens produce similar performance improvements; however, there was a trend toward greater hypertrophy-related gene expression and muscle fiber hypertrophy in the ST group.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Biopsy
  • Calcineurin / metabolism
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism
  • DNA-Binding Proteins
  • Gene Expression* / genetics
  • Gene Expression* / physiology
  • Humans
  • Hypertrophy / genetics*
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Muscle Fibers, Skeletal / pathology*
  • Muscle Proteins / metabolism
  • Muscle Strength / genetics
  • Muscle Strength / physiology*
  • Phenotype
  • Polymerase Chain Reaction
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Proteins / genetics
  • Proteins / metabolism
  • RNA, Messenger / genetics
  • Rapamycin-Insensitive Companion of mTOR Protein
  • Regulatory-Associated Protein of mTOR
  • Resistance Training / methods*
  • TOR Serine-Threonine Kinases

Substances

  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • DNA-Binding Proteins
  • Intracellular Signaling Peptides and Proteins
  • Muscle Proteins
  • Proteins
  • RCAN1 protein, human
  • RICTOR protein, human
  • RNA, Messenger
  • RPTOR protein, human
  • Rapamycin-Insensitive Companion of mTOR Protein
  • Regulatory-Associated Protein of mTOR
  • MTOR protein, human
  • Protein Serine-Threonine Kinases
  • TOR Serine-Threonine Kinases
  • Calcineurin