نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری، دانشکده تربیت‌بدنی و علوم ورزشی ، دانشگاه خوارزمی تهران

2 استادیار، دانشکده تربیت بدنی و علوم ورزشی، دانشگاه تهران

3 دانشیار، دانشکده مهندسی پزشکی، دانشگاه صنعتی امیرکبیر

چکیده

سفتی پا پارامتر اصلی در مدل جرم-فنر برای حرکت انسان است و ارتباط آن با موفقیت در برخی از عملکردهای ورزشی نشان داده شده است. پژوهش حاضر با هدف تعیین ارتباط میان سفتی پا و کارایی چرخة کشش-انقباض در اجرای پرش‌های عمودی انجام شد. 12 اسکواش‌باز زن نخبه (سن 9/5 ±8/22 سال، وزن 37/3 ±62/60 کیلوگرم، قد 06/0 ±65/1 متر) داوطلب شرکت در این پژوهش شدند و آزمون هاپینگ با فرکانس 2/2 هرتز و دو پرش عمودی اسکات‌جامپ و کانترموومنت‌جامپ را انجام دادند. سفتی پا از داده‌های آزمون هاپینگ به دست آمد و با وزن آزمودنی‌ها نرمال شد و اختلاف ارتفاع دو پرش به عنوان شاخص کارایی چرخة کشش-انقباض در نظر گرفته شد. سفتی پای نرمال با اختلاف ارتفاع پرش‌ها رابطة معنادار مثبت نشان داد. بر اساس این یافته، افزایش سفتی پا می‌تواند به بهبود کارایی چرخه کشش-انقباض در پرش عمودی و حرکات مشابه منجر شود.

کلیدواژه‌ها

عنوان مقاله [English]

The Relationship between Leg Stiffness and The Stretch-Shortening Cycle Efficiency During Vertical Jump in Female Athletes

نویسندگان [English]

  • mojtaba ashrostaghi 1
  • Elham Shirzad 2
  • Ahmad Reza Arshi 3

چکیده [English]

Leg stiffness is the main parameter in mass-spring model of human movement and its correlation to success of some sports performances has been previously presented. The current study was performed to determine the relationship between leg stiffness and stretch-shortening cycle efficiency during vertical jumps. 12 elite female squash players (age 22.8 ± 5.9 yrs, weight 60.62 ± 3.37 kg, height 165 ± 0.06 m) volunteered to the study and performed the hopping test at 2.2 Hz and two vertical jumps, squat jump and countermovement jump. Leg stiffness was measured using hopping test data and was normalized by body mass. Difference in jump height between two jumps was considered as the criterion of stretch-shortening cycle efficiency. Normalized leg stiffness showed positive significant correlation to difference in jump height. On the base of this result, enhancing the leg stiffness may improve the stretch-shortening cycle efficiency in vertical jump and the similar movements.

کلیدواژه‌ها [English]

  • Leg Stiffness
  • Mass-Spring Model
  • Stretch-Shortening Cycle
  • Squat Jump
  • Countermovement Jump
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