Expression of genes related to muscle plasticity after strength and power training regimens.
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.
School of Physical Education and Sport, University of São Paulo, São Paulo, SP, Brazil.
L
L
Lamas
M S
MS
Aoki
C
C
Ugrinowitsch
G E R
GE
Campos
M
M
Regazzini
A S
AS
Moriscot
V
V
Tricoli
D048868:Adaptor Proteins, Signal Transducing; D001706:Biopsy; D019703:Calcineurin / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins; D015870:Gene Expression / Q000235:genetics / Q000502:physiology; D006801:Humans; D006984:Hypertrophy / Q000235:genetics*; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D018485:Muscle Fibers, Skeletal / Q000473:pathology*; D009124:Muscle Proteins / Q000378:metabolism; D053580:Muscle Strength / Q000235:genetics / Q000502:physiology*; D010641:Phenotype; D016133:Polymerase Chain Reaction; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D000076226:Rapamycin-Insensitive Companion of mTOR Protein; D000076223:Regulatory-Associated Protein of mTOR; D055070:Resistance Training / Q000379:methods*; D058570:TOR Serine-Threonine Kinases
D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009124:Muscle Proteins; D011506:Proteins; C108612:RCAN1 protein, human; C492571:RICTOR protein, human; D012333:RNA, Messenger; C463659:RPTOR protein, human; D000076226:Rapamycin-Insensitive Companion of mTOR Protein; D000076223:Regulatory-Associated Protein of mTOR; C546842:MTOR protein, human; D017346:Protein Serine-Threonine Kinases; D058570:TOR Serine-Threonine Kinases; D019703:Calcineurin