Home > Riviste > The Journal of Sports Medicine and Physical Fitness > Fascicoli precedenti > The Journal of Sports Medicine and Physical Fitness 1999 June;39(2) > The Journal of Sports Medicine and Physical Fitness 1999 June;39(2):83-92

ULTIMO FASCICOLO
 

ARTICLE TOOLS

Estratti

THE JOURNAL OF SPORTS MEDICINE AND PHYSICAL FITNESS

Rivista di Medicina, Traumatologia e Psicologia dello Sport


Indexed/Abstracted in: Chemical Abstracts, CINAHL, Current Contents/Clinical Medicine, EMBASE, PubMed/MEDLINE, Science Citation Index Expanded (SciSearch), Scopus
Impact Factor 1,215


eTOC

 

ORIGINAL ARTICLES  


The Journal of Sports Medicine and Physical Fitness 1999 June;39(2):83-92

Copyright © 1999 EDIZIONI MINERVA MEDICA

lingua: Inglese

Hemoglobin near-infrared spectroscopy and surface EMG study in muscle ischaemia and fatiguing isometric contraction

Alfonsi E. 1, Pavesi R. 2, Merlo I. M. 1, Gelmetti A. 3, Zambarbieri D. 2, Lago P. 3, Arrigo A. 1, Reggiani C. 4, Moglia A. 1, 5

1 Clinical Neurophysiology Unit, Fondazione “Istituto Neurologico C. Mondino”, IRCCS, University of Pavia, Pavia, Italy; 2 Department of Systems and Computer Science, University of Pavia, Pavia, Italy; 3 Policlinico “S. Matteo”, IRCCS, University of Pavia, Pavia, Italy; 4 Department of Human Physiology, University of Pavia, Pavia, Italy; 5 Interdisciplinar Center of Sport Medicine, University of Pavia, Pavia, Italy


PDF  


Background. To ­assess how mus­cle ischae­mia and iso­met­ric fatigu­ing con­trac­tion influ­ence oxy­gen con­tent in stri­at­ed mus­cle.
Methods. We simul­ta­ne­ous­ly meas­ured chang­es in hemo­glo­bin ­near-­infrared (NIR) spec­tros­co­py and in sur­face EMG ­before, dur­ing, and ­after mus­cle ischae­mia and ischae­mia ­plus mus­cle iso­met­ric fatigu­ing con­trac­tion. Seventeen ­healthy ­male sub­jects (age ­range: 19-40 yrs) ­were exam­ined in our Clinical Neurophysiology Unit. Test I (9 sub­jects): hemo­glo­bin NIR spec­tros­co­py and stim­u­lat­ed sur­face EMG ­were meas­ured for 2 min­utes at ­rest, for 4 min­utes dur­ing com­plete ischae­mia of tibi­al­is ante­ri­or mus­cle, and for ­twelve min­utes dur­ing recov­ery. Test II (all sub­jects): hemo­glo­bin NIR spec­tros­co­py and sur­face EMG ­were meas­ured for 2 min­utes ­with the sub­jects per­form­ing ­brief non-fatigu­ing con­trac­tions, for 4 min­utes ­with the sub­ject per­form­ing max­i­mal iso­met­ric con­trac­tion in com­plete ischae­mia, and for ­twelve min­utes dur­ing recov­ery. EMG param­e­ters meas­ured: ­median den­sity fre­quen­cy (MDF); mus­cle ­fiber con­duc­tion veloc­ity (­MFCV). NIR spec­tros­co­py param­e­ters meas­ured: per­cent­age of ampli­tude decre­ment (%AD) and ­nadir ­time (NT) dur­ing ischae­mia and ischaem­ic ­effort; ­half-recov­ery ­time (1/2 RT) ­from ischae­mia ­effort.
Results. At EMG, we ­observed a sig­nif­i­cant ­shift ­towards low­er val­ues of ­both ­MFCV and MDF dur­ing fatigu­ing iso­met­ric con­trac­tion. MDF recov­ery was fast­er ­then ­MFCV recov­ery. At NIR spec­tros­co­py, the 1/2 RT ­slowed a ­fast pat­tern in ­twelve sub­jects and a ­slow pat­tern in ­five. A sig­nif­i­cant rela­tion­ship was ­found ­between AD% and 1/2 RT val­ues of ­test I and AD% and 1/2 val­ues of ­test II. We ­found a pos­i­tive rela­tion­ship ­between NT and 1/2 RT in ­test II.
Conclusions. Surface EMG and hemo­glo­bin NIR spec­tros­co­py can be ­applied simul­ta­ne­ous­ly to eval­u­ate ­both ­fatigue inten­sity and ­blood ­flow chang­es in stri­at­ed mus­cle.

inizio pagina

Publication History

Per citare questo articolo

Corresponding author e-mail