Akademik Veri Yönetim Sistemi
ISOKINETICS AND EXERCISE SCIENCE, cilt.14, sa.3, ss.213-220, 2006 (SCI-Expanded)
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 mate 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 x 3 x 2 ANOVA with repeated measures, significant joint angle effect (p < 0.001), contraction type effect (p < 0.001) and significant frequency x 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.