Investigation of the Effect of Unilateral Squat Depth on Bar Velocity at Different Relative Loads

Abstract

The aim of this study was to examine the relationship between unilateral squat depth and bar velocity at different relative loads. Ten male athletes from Halic University School of Physical Education and Sports (the age of 22.90±1.28 years old; a body height of 175,90±5.36cm and a body weight of 75.38±7.78kg) who had been doing active exercises for at least three years and had mastered unilateral (one-sided) and bilateral (two-sided) exercise models, were participated to this study as voluntarily. In data collection, PUSH Band™ Pro v2.0 as linear accelerometer was used to detect bar velocity and Qualisys Track Manager (QTM) 2020.3 Version (EU, Sweden) which is a three-dimensional motion analysis system for squat depth was also used. Athletes; applied a modified single leg squat exercise. The exercise was performed in the back grip. Weightless bar (20kg) was applied on both legs first, then randomly; they performed 5 repetitions of 1TM at 40%, 60%, 80% loads. In the measurements, the velocity of the bar was calculated through the Push Band placed on the bar; squat depths at different loads were calculated with the 3D motion analysis system. For statistical analysis of data, IBM SPSS Version 25 program were used. Variance Analyses in Repeated Measures were applied and for pairwise comparisons T-test were used. Significant differences were obtained in almost all bar velocities at different relative loads (p<0.05). As a result of the correlation analysis, it was determined that there was no significant relationship between bar velocity and squat depth (p>0.05). In finally, bar velocity variables at different loads caused significant changes with increasing loads on both legs. The amount of load can be considered as a parameter that affects the velocity of the bar in the direction of decreasing it. 

Keywords

• Unilateral
• Relative Load
• Bar Velocity
• Squat Depth

Farklı Yüklerde Yapılan Unilateral Squat Hareketinde Çömelme Derinliği ile Bar Hızı Arasındaki İlişkinin İncelenmesi

Öz

Bu çalışmanın amacı, farklı yüklerde modifiye edilmiş unilateral squat performansında çömelme derinliği ile bar hızı arasındaki ilişkinin incelenmesidir. Çalışmanın örneklem grubunu, Haliç Üniversitesi Beden Eğitimi ve Spor Yüksekokulu’nda okuyan, en az üç yıl boyunca aktif egzersiz yapan, unilateral (tek taraflı) ve bilateral (iki taraflı) egzersiz modellerine hâkim; yaş 22,90±1,28yıl; boy 175,90±5,36cm ve vücut ağırlığı 75,38±7,78kg olan 10 gönüllü erkek sporcu oluşturmuştur. Verilerin toplanmasında, bar hızının tespit edilmesi için doğrusal hız ölçer olarak PUSH Band™ Pro v2.0 ve squat performansı esnasında çömelme derinliği için üç boyutlu hareket analizi sistemi olan Qualisys Track Manager (QTM) 2020.3 Versiyon (AB, İsveç) kullanılmıştır. Sporcular; modifiye tek bacak squat egzersizi uygulamışlardır. Egzersizi arkadan tutuşta her iki ekstremitede önce ağırlıksız bar da (20kg), ardından random olarak; 1TM’nin %40, %60, %80 yüklerde 5 tekrar yapacak şekilde gerçekleştirmişlerdir. Ölçümlerde, bar üzerine yerleştirilen Push Band aracılığıyla bar hızı hesaplanmış; 3D hareket analiz sistemiyle de farklı yüklerdeki çömelme derinlikleri hesaplanmıştır. Verilerin istatistiksel analizi, IBM SPSS Versiyon 25 programı kullanılarak; tekrarlı ölçümlerde varyans analizi ve ikili karşılaştırmalarda T-testi uygulanarak yapılmıştır. Farklı relatif yüklerde bar hızlarının hemen hepsinde anlamlı farklılıklar elde edilmiştir (p<0,05). Yapılan korelasyon analizi sonucunda bar hızı ve çömelme derinliği arasında anlamlı bir ilişki olmadığı tespit edilmiştir (p>0,05). Sonuç olarak, farklı yüklerdeki bar hızı değişkenlerinin her iki ekstremite de yüklerin artmasıyla anlamlı değişikliklere sebep olmuştur. Yük miktarı, barı hızını azaltacak yönde etkileyen bir parametre olarak değerlendirilebilir. 

Anahtar Kelimeler

• Unilateral
• Relatif Yük
• Bar Hızı
• Squat Derinliği

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