Faculty Collaboration Database

Spectral properties of H-reflex recordings after an acute bout of whole-body vibration. J Strength Cond Res 2012 Jul;26(7):1915-9

Date

10/04/2011

Pubmed ID

21964429

DOI

10.1519/JSC.0b013e3182392ae9

Scopus ID

2-s2.0-84863637387 (requires institutional sign-in at Scopus site)

Abstract

Although research supports the use of whole-body vibration (WBV) to improve neuromuscular performance, the mechanisms for these improvements remain unclear. The purpose of this study was to identify the effect of WBV on the spectral properties of electrically evoked H-reflex recordings in the soleus (SOL) muscle. The H-reflex recordings were measured in the SOL muscle of 20 participants before and after a bout of WBV. The H-reflexes were evoked every 15 seconds for 150 seconds after WBV. A wavelet procedure was used to extract spectral data, which were then quantified with a principle components analysis. Resultant principle component scores were used for statistical analysis. The analysis extracted 1 principle component associated with the intensity of the myoelectric spectra and 1 principle component associated with the frequency. The scores of the principle component that were related to the myoelectric intensity were smaller at 30 and 60 milliseconds after WBV than before WBV. The WBV transiently decreased the intensity of myoelectric spectra during electrically evoked contractions, but it did not influence the frequency of the spectra. The decrease in intensity likely indicates a smaller electrically evoked muscle twitch response, whereas the lack of change in frequency would indicate a similar recruitment pattern of motor units before and after WBV.

Author List

Kipp K, Johnson ST, Hoffman MA

Author

Kristof Kipp BS,MS,PhD Assistant Professor in the Physical Therapy department at Marquette University

MESH terms used to index this publication - Major topics in bold

Adult
Chi-Square Distribution
Electromyography
Female
Humans
Male
Motor Neurons
Muscle, Skeletal
Principal Component Analysis
Recruitment, Neurophysiological
Reflex
Statistics, Nonparametric
Vibration
Wavelet Analysis
Young Adult