Affiliations: [a] Baskent University, Department of Sport Sciences,
Ankara, Turkey | [b] Hacettepe University, School of Sport Sciences and
Technology, Ankara, Turkey
Note: [] Address for correspondence: Ayse Kin-Isler, PhD, Baskent
University, Faculty of Health Sciences, Department of Sport Sciences, Baglica
Kampusu, Eskisehir Yolu 20. km, 06530 Ankara, Turkey. Tel.: +90 312 2341010
1607; Fax: +90 312 2341157; E-mail: akisler@baskent.edu.tr
Abstract: The purpose of the present study was to determine the effects
vibration, applied with different frequencies at different joint angles, on
maximal isometric muscle contraction. Forty male volunteers were randomly and
equally assigned to one of the four different vibration stimulation groups as 6
Hz, 12 Hz, 24 Hz and 48 Hz. Subjects performed three consecutive isometric
maximal voluntary contractions (MVC) with and without vibration for six seconds
with one-minute interval at 90, 120 and 150 degrees of elbow angles in random
order. During MVC with vibration tests vibration was applied to upper arm 10
seconds before the contraction begins and continued throughout the MVC.
According to results of 4 × 3 ×
2 ANOVA with repeated measures, significant joint angle effect
(p<0.001), contraction type effect
p<0.001) and significant frequency ×
contraction type interaction (p<0.001) was found. It can be
concluded that vibration stimulation resulted in increased isometric MVC.
Results also suggested that stimulating muscles with 6, 12 and 24 Hz of
vibration resulted in increased isometric MVC, 48 Hz of vibration on the other
hand resulted in decreased isometric MVC. In addition, the length of the
contracting muscle did not affect the vibration load that was applied with
different frequencies.
