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Maximal lengthening contractions increase p70 S6 kinase phosphorylation in human skeletal muscle in the absence of nutritional supply.
Am J Physiol Endocrinol Metab. 2006 Dec; 291(6):E1197-205.AJ

Abstract

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.

Authors+Show Affiliations

University College of Physical Education and Sports, Box 5626, Stockholm, S-114 86, Sweden.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

16835402

Citation

Eliasson, Jörgen, et al. "Maximal Lengthening Contractions Increase P70 S6 Kinase Phosphorylation in Human Skeletal Muscle in the Absence of Nutritional Supply." American Journal of Physiology. Endocrinology and Metabolism, vol. 291, no. 6, 2006, pp. E1197-205.
Eliasson J, Elfegoun T, Nilsson J, et al. Maximal lengthening contractions increase p70 S6 kinase phosphorylation in human skeletal muscle in the absence of nutritional supply. Am J Physiol Endocrinol Metab. 2006;291(6):E1197-205.
Eliasson, J., Elfegoun, T., Nilsson, J., Köhnke, R., Ekblom, B., & Blomstrand, E. (2006). Maximal lengthening contractions increase p70 S6 kinase phosphorylation in human skeletal muscle in the absence of nutritional supply. American Journal of Physiology. Endocrinology and Metabolism, 291(6), E1197-205.
Eliasson J, et al. Maximal Lengthening Contractions Increase P70 S6 Kinase Phosphorylation in Human Skeletal Muscle in the Absence of Nutritional Supply. Am J Physiol Endocrinol Metab. 2006;291(6):E1197-205. PubMed PMID: 16835402.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Maximal lengthening contractions increase p70 S6 kinase phosphorylation in human skeletal muscle in the absence of nutritional supply. AU - Eliasson,Jörgen, AU - Elfegoun,Thibault, AU - Nilsson,Johnny, AU - Köhnke,Rickard, AU - Ekblom,Björn, AU - Blomstrand,Eva, Y1 - 2006/07/11/ PY - 2006/7/13/pubmed PY - 2006/12/13/medline PY - 2006/7/13/entrez SP - E1197 EP - 205 JF - American journal of physiology. Endocrinology and metabolism JO - Am J Physiol Endocrinol Metab VL - 291 IS - 6 N2 - 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. SN - 0193-1849 UR - https://www.unboundmedicine.com/medline/citation/16835402/Maximal_lengthening_contractions_increase_p70_S6_kinase_phosphorylation_in_human_skeletal_muscle_in_the_absence_of_nutritional_supply_ L2 - https://journals.physiology.org/doi/10.1152/ajpendo.00141.2006?url_ver=Z39.88-2003&amp;rfr_id=ori:rid:crossref.org&amp;rfr_dat=cr_pub=pubmed DB - PRIME DP - Unbound Medicine ER -