Differences in activation patterns of knee flexor muscles during concentric and eccentric exercises

Takashi Ono, Toru Okuwaki, Toru Fukubayashi

    Research output: Contribution to journalArticle

    28 Citations (Scopus)

    Abstract

    The purpose of this study was to clarify the activation patterns among knee flexor muscles during knee flexion exercises by electromyography (EMG) and muscle functional magnetic resonance imaging (mfMRI). Seven male volunteers performed knee flexion exercises with each unilateral limb at 120% of 1 repetition of maximum (1RM) and 50% of 1RM. EMG activity was recorded for the biceps femoris long head, semitendinosus (ST), semimembranosus (SM), and gracilis (G) muscles; mfMRI T2 values in the same muscles were measured at rest and immediately after exercise. The study found that EMG of the ST and G was significantly higher than that of the ST during the exercises at 120% 1RM. T2 value changes in the ST and G were significantly higher than in the biceps femoris long head (BFsh) and ST in both exercises. It was concluded that the activation patterns among knee flexor muscles during knee flexion were nonuniform for the respective muscles.

    Original languageEnglish
    Pages (from-to)188-198
    Number of pages11
    JournalResearch in Sports Medicine
    Volume18
    Issue number3
    DOIs
    Publication statusPublished - 2010 Jul

    Fingerprint

    Knee
    Exercise
    Muscles
    Electromyography
    Magnetic Resonance Imaging
    Hamstring Muscles
    Volunteers
    Extremities

    Keywords

    • electromyography
    • functional property
    • hamstrings
    • muscle functional magnetic resonance imaging

    ASJC Scopus subject areas

    • Orthopedics and Sports Medicine
    • Physical Therapy, Sports Therapy and Rehabilitation
    • Medicine(all)

    Cite this

    Differences in activation patterns of knee flexor muscles during concentric and eccentric exercises. / Ono, Takashi; Okuwaki, Toru; Fukubayashi, Toru.

    In: Research in Sports Medicine, Vol. 18, No. 3, 07.2010, p. 188-198.

    Research output: Contribution to journalArticle

    Ono, Takashi ; Okuwaki, Toru ; Fukubayashi, Toru. / Differences in activation patterns of knee flexor muscles during concentric and eccentric exercises. In: Research in Sports Medicine. 2010 ; Vol. 18, No. 3. pp. 188-198.
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