نوع مقاله : مقاله پژوهشی

نویسندگان

1 دکتری بیومکانیک ورزشی، دانشگاه خوارزمی تهران

2 استاد بیومکانیک ورزشی، دانشگاه خوارزمی تهران

3 استادیار فیزیولوژی ورزشی، پژوهشگاه تربیت بدنی و علوم ورزشی

4 استادیار دانشکده ارتوپدی فنی دانشگاه علوم بهزیستی و توانبخشی تهران

چکیده

هدف‌ از این پژوهش، مقایسۀ سفتی اندام تحتانی و حداکثر نیروی عکس‌العمل عمودی زمین طی حرکت روی سطوح الاستیک پهن با تأکید بر آگاهی از میزان سفتی بود. بدین‌منظور، سفتی اندام تحتانی و نیروی عکس‌العمل زمین 30 مرد جوان در تکالیف هاپینگ و فرود از سکو روی پنج سطح با سفتی 200 تا 500 کیلونیوتن بر متر مورد‌اندازه‌گیری قرار گرفت. نتایج آزمون آنالیز واریانس نشان می‌دهد که بین سفتی اندام در سطوح مختلف و نیز قبل و بعد از آشنایی با سطح، تفاوت معناداری وجود دارد. با توجه به یافته‌های این پژوهش مشخص می‌شود که انسان بر‌خلاف اجسام، ‌هنگام برخورد با سطحی جدید، خود را با آن منطبق می‌کند تا از این طریق و بسته به تکلیف مورد‌نظر، دینامیک طبیعی مرکز جرم و بازده حرکت حفظ شده و ‌نیروها تعدیل گردند. 

 

کلیدواژه‌ها

عنوان مقاله [English]

Comparison of Leg Stiffness and Maximum Ground Reaction Force on Area-Elastic Surfaces with Different Stiffness with Focus on Surface Familiarity

نویسندگان [English]

  • Seyed Abbas Farjad Pezeshk 1
  • Heidar Sadeghi 2
  • Mohammad Shariatzadeh Joneidi 3
  • Zahra Safaeepoor 4

1 Ph.D. in Sports Biomechanics, Kharazmi University

2 Professor of Sports Biomechanics, Kharazmi University

3 Assistant Professor of Sport Physiology, Sports Sciences Research Institute of Iran

4 Assistant Professor, Orthotics and Prosthetics Department, University of Social Welfare and Rehabilitation Sciences

چکیده [English]

The purpose of this study was to compare vertical stiffness and maximum ground reaction force on elastic surfaces with different stiffness with focus on surface familiarity. Vertical stiffness and maximum ground reaction force during hopping and landing from height on five surfaces with 200–500 kN stiffness were measured for 30 young men. The results of the analysis of variance showed that there were significant differences in leg stiffness on different surfaces, and also before and after familiarity with surfaces. According to the results of this study, unlike other objects, human adapts himself when encountering new surface and in this way, depending on the task, can keep normal center of mass pattern and reduce the forces. 

کلیدواژه‌ها [English]

  • Leg Stiffness
  • Area-Elastic Surface
  • Ground Reaction Force
  • Hopping
  • Landing
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