کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5042040 1474215 2016 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Full Length ArticleSelective activation of lower leg muscles during maximum voluntary isometric contractions
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب شناختی
پیش نمایش صفحه اول مقاله
Full Length ArticleSelective activation of lower leg muscles during maximum voluntary isometric contractions
چکیده انگلیسی


- We tested the activity of the lower leg muscles during isometric contractions (MVIC).
- Subjects performed MVICs around the axes of the subtalar and talo-crural joints.
- Each shank muscle shows a specific activation determined by its anatomical course.
- The activation of the shank muscles is geared to their biomechanical advantage.
- The activation of tibialis anterior and peroneus longus is influenced by foot type.

The pronators and supinators play a key role in the medio-lateral stability of the ankle joint complex (i.e. talo-crural and subtalar joints). We hypothesized that each shank muscle has a specific activation pattern determined by its anatomical course around the axes of the subtalar and talo-crural joints. A secondary objective was to examine the effect of foot posture on these activation patterns. Forty-nine young adults (25 normal-arched feet, 24 flat-arched feet) performed maximum voluntary isometric contractions against manual resistance in four movement directions: plantarflexion (PF), dorsiflexion (DF), pronation (PRO) and supination (SUP). Electromyographic activity was recorded from tibialis posterior (TP) and peroneus longus (PL) with intramuscular electrodes, and gastrocnemius medialis (GM) and tibialis anterior (TA) with surface electrodes. When compared to their agonist function, all muscles were co-activated at significantly lower levels in their synergistic function (GM: 23% during SUP, TA: 72% during SUP; TP: 42% during PF, PL: 52% during PF) (p < 0.001). A significant interaction between foot posture and contraction type was evident for TA. During isometric contractions, the electromyographic activity of the shank muscles is geared to their biomechanical advantage according to their position relative to the subtalar and talo-crural joint axes.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Human Movement Science - Volume 50, December 2016, Pages 30-37
نویسندگان
, , , , ,