Kinesiology, Vol. 36 No. 1., 2004.
Conference paper
Differentiation of skeletal muscles in 9-year-old children
Rado Pišot
Katarina Kerševan
Srdjan Djordjević
Vladimir Medved
Jernej Završnik
Boštjan Šimunič
Abstract
Motor activity in childhood is extremely important for the general development of a child, yet there is still not enough information about children's motor development. Contractile properties of skeletal muscles in children mainly reflect their inherited muscle characteristics. In early childhood the muscular structure is made mostly of slow-twitch muscular fibers. The finer motor abilities follow gradually from age three onwards when the muscular fiber is classified into slow-twitch, rapid and fast-twitch. The fastest development of this classification (muscle differentiation) takes place until the age of three and continues until the end of puberty. In this study muscles of 187 healthy 9-year-old children were assessed using a non-invasive and selective measuring method called tensiomyography (TMG) in order to estimate the stage of differentiation of their skeletal muscles. TMG enables selective measurements of radial muscle belly displacement as a response to a single electrical stimulus. The children measured were involved in this study after written consent had been obtained. TMG data were calculated on selected muscles: m. biceps brachii, m. vastus lateralis, m. biceps femoris and m. erector spinae. After TMG measurements had been carried out, each child performed a 14-metre sprint velocity test. TMG parameters were calculated and compared in three groups, namely, the ten fastest children, the ten slowest children and the average result of all the children measured. The ten fastest children had a smaller sum of delay time and contraction time, which correlates with a higher percentage of fast-twitch muscle fibers. They also had a significantly higher level of muscle activation.
Keywords
tensiomyography; electrical stimulation; contractile properties
Hrčak ID:
4225
URI
Publication date:
28.6.2004.
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