PMID- 16835402
OWN - NLM
STAT- MEDLINE
DCOM- 20061212
LR  - 20211203
IS  - 0193-1849 (Print)
IS  - 0193-1849 (Linking)
VI  - 291
IP  - 6
DP  - 2006 Dec
TI  - Maximal lengthening contractions increase p70 S6 kinase phosphorylation in human 
      skeletal muscle in the absence of nutritional supply.
PG  - E1197-205
AB  - The aim of this study was to compare the training stimuli of eccentric 
      (lengthening) and concentric (shortening) contractions regarding the effect on 
      signaling enzymes involved in protein synthesis. Ten male subjects performed 4 x 
      6 maximal eccentric contractions on one leg followed by 4 x 6 maximal concentric 
      contractions on the other. Six additional subjects performed the same protocol, 
      but with maximal concentric and submaximal eccentric exercise of equal force to 
      that of the maximal concentric contractions. Muscle biopsy samples were taken 
      from the vastus lateralis before, immediately after, and 1 and 2 h after exercise 
      in both legs. The average peak force produced during the maximal eccentric 
      exercise was 31% higher than during the maximal concentric exercise, 2,490 
      (+/-100) vs. 1,894 (+/-108) N (P < 0.05). The maximal eccentric contractions led 
      to two- to eightfold increases in the phosphorylation of p70 S6 kinase (p70(S6k)) 
      and the ribosomal protein S6 that persisted for 2 h into recovery but no 
      significant changes in phosphorylation of Akt or mammalian target of rapamycin 
      (mTOR). Maximal concentric and submaximal eccentric contractions did not induce 
      any significant changes in Akt, mTOR, p70(S6k), or S6 phosphorylation up to 2 h 
      after the exercise. The results indicate that one session of maximal eccentric 
      contractions activates p70(S6k) in human muscle via an Akt-independent pathway 
      and suggest that maximal eccentric contractions are more effective than maximal 
      concentric contractions in stimulating protein synthesis in the absence of a 
      nutritional intake, an effect that may be mediated through a combination of 
      greater tension and stretching of the muscle.
FAU - Eliasson, Jorgen
AU  - Eliasson J
AD  - University College of Physical Education and Sports, Box 5626, Stockholm, S-114 
      86, Sweden.
FAU - Elfegoun, Thibault
AU  - Elfegoun T
FAU - Nilsson, Johnny
AU  - Nilsson J
FAU - Kohnke, Rickard
AU  - Kohnke R
FAU - Ekblom, Bjorn
AU  - Ekblom B
FAU - Blomstrand, Eva
AU  - Blomstrand E
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20060711
PL  - United States
TA  - Am J Physiol Endocrinol Metab
JT  - American journal of physiology. Endocrinology and metabolism
JID - 100901226
RN  - 0 (Blood Glucose)
RN  - 33X04XA5AT (Lactic Acid)
RN  - EC 2.7.- (Protein Kinases)
RN  - EC 2.7.1.1 (MTOR protein, human)
RN  - EC 2.7.11.1 (Proto-Oncogene Proteins c-akt)
RN  - EC 2.7.11.1 (Ribosomal Protein S6 Kinases)
RN  - EC 2.7.11.1 (Ribosomal Protein S6 Kinases, 70-kDa)
RN  - EC 2.7.11.1 (TOR Serine-Threonine Kinases)
SB  - IM
MH  - Adult
MH  - Blood Glucose/metabolism
MH  - Blotting, Western
MH  - Electromyography
MH  - Exercise/physiology
MH  - Humans
MH  - Lactic Acid/blood
MH  - Leg/physiology
MH  - Male
MH  - Muscle Contraction/physiology
MH  - Muscle, Skeletal/*metabolism/*physiology
MH  - Nutritional Physiological Phenomena
MH  - Phosphorylation
MH  - Protein Kinases/metabolism
MH  - Proto-Oncogene Proteins c-akt/metabolism
MH  - Ribosomal Protein S6 Kinases/metabolism
MH  - Ribosomal Protein S6 Kinases, 70-kDa/*metabolism
MH  - Signal Transduction/physiology
MH  - TOR Serine-Threonine Kinases
EDAT- 2006/07/13 09:00
MHDA- 2006/12/13 09:00
CRDT- 2006/07/13 09:00
PHST- 2006/07/13 09:00 [pubmed]
PHST- 2006/12/13 09:00 [medline]
PHST- 2006/07/13 09:00 [entrez]
AID - 00141.2006 [pii]
AID - 10.1152/ajpendo.00141.2006 [doi]
PST - ppublish
SO  - Am J Physiol Endocrinol Metab. 2006 Dec;291(6):E1197-205. doi: 
      10.1152/ajpendo.00141.2006. Epub 2006 Jul 11.