Abstract:
:Low frequency audible vibrations are produced by human skeletal muscles undergoing sustained contraction. The effect is easily demonstrable with an electronic stethoscope which amplifies sound below 50 Hz. Autocorrelation analysis of the signal shows that it is periodic with a frequency 25 +/- 2.5 Hz. The quality of the sound is the same for all the skeletal muscles tested and is unaffected by changes in tension, ambient temperature, and blood flow. Electrically-stimulated contraction produces a sound which is indistinguishable from voluntary contraction. The amplitude of the sound increases linearly with tension. The sound signals are uncorrelated both in frequency and phase with electromyographic signals obtained simultaneously while the muscle is contacted. Arguments are presented to show that the sounds may be an intrinsic property of muscle contraction.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Oster G,Jaffe JSdoi
10.1016/S0006-3495(80)85080-6subject
Has Abstractpub_date
1980-04-01 00:00:00pages
119-27issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(80)85080-6journal_volume
30pub_type
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