Human muscle energetics during voluntary and electrically induced isometric contractions as measured by 31P NMR spectroscopy
Deutscher übersetzter Titel: | Energiestoffwechsel im menschlichen Muskel bei willkuerlichen und elektrisch stimulierten isometrischen Kontraktionen, gemessen mit Hilfe der 31P-Magnetresonanzspektroskopie |
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Autor: | Vanderthommen, M.; Gilles, R.; Carlier, P.; Ciancabilla, F.; Zahlan, O.; Sluse, F.; Crielaard, J.M. |
Erschienen in: | International journal of sports medicine |
Veröffentlicht: | 20 (1999), 5, S. 279-283, Lit. |
Format: | Literatur (SPOLIT) |
Publikationstyp: | Zeitschriftenartikel |
Medienart: | Gedruckte Ressource Elektronische Ressource (online) |
Sprache: | Englisch |
ISSN: | 0172-4622, 1439-3964 |
DOI: | 10.1055/s-2007-971131 |
Schlagworte: | |
Online Zugang: | |
Erfassungsnummer: | PU199908401134 |
Quelle: | BISp |
Abstract des Autors
Electrical stimulation (ES) and voluntary contraction (VC) were compared in the quadriceps muscle of ten male volunteers. In both modes, a workload corresponding to 20% of maximal voluntary contraction was applied during 64 isometric contraction (5.5 s)-relaxation (5.5 s) cycles. The protocols were performed in a 1.5 T whole-body magnet. The Pi/PCr ratio and the intracellular pH (pHi) were monitored by 31P NMR spectroscopy during baseline, exercise and recovery periods, in a superficial region of the vastus medialis. During baseline, the Pi/PCr ratio (0.12 vs. 0.10) and the pHi (7.01 vs. 7.00) were comparable in both conditions. During exercise, the Pi/PCr ratio was higher (0.36 vs. 0.14) and the pHi was lower (6.85 vs. 7.07) during ES than during VC. For the same external work production, these results reflect a different metabolic solicitation in the ES quadriceps than in the VC ones. Verf.-Referat