Evaluation of a novel device to assess combined knee flexion and hip extension, and hip flexion force production capability

Calderbank, Jessica

Abstract

Background: The late flight phase (FP) of the sprint running action is essential to enable the ‘forward most limb’ to prepare for ground contact. Kinetic and kinematic factors during the FP show association to sprinting speed. While isometric assessments are widely used to evaluate sprint metrics, they often replicate weightlifting positions and not sprint positions. However, isometric isokinetic dynamometry (IKD) and handheld dynamometry (HHD) do allow limbs to be manoeuvred into joint angles similar to the FP of sprinting, though they test unilaterally and don’t specifically replicate sprinting positions. Therefore, Performance Biomechanics created The Biostrain, an isometric device that is capable of assessing isometric force-time characteristics in similar positions to the FP of sprinting. Aims: This thesis provides a systematic review of IKD and HHD literature to investigate reliability and validity (study 1). This thesis also aims to assess the Biostrain (over 150ms, 200ms, 250ms and peak force) reliability, and validity compared to IKD (peak force) (study 2) and assess its correlation with 20 m sprint performance (study 3). Study 1 Methods: A literature search was conducted using literature databases and assessment of study quality was assessed using a modified Downs and Blacks scale. Study 2 and 3 Methods: Eighteen healthy active subjects participated (n = 18; age = 23.3 ± 5.1 years; height: 173.9 ± 5.8 cm; mass: 69.4 ± 12.8 kg). Biostrain methods: Subjects completed three trials with left leg forwards and right leg back and three trials with right leg forward and left leg back without the use of hands to stabilise positions and again repeated with hand stability (study 2 and study 3). IKD Methods: 3 × 5 s maximum effort trials were carried out in three different positions on each leg that replicated individual limbs during Biostrain testing (study 2). Sprinting Methods: Subjects completed 3 x 20 m maximum effort sprints (study 3). Study 1 systematics review resutls: Out of an inital 421, 19 articles were deemed eligible. The main overall findings showed IKD was more reliable than HHD (IKD ICC: 0.83 to 0.99; HHD ICC: 0.49 to 0.99). The quality of methods for IKD ranged between 73 to 91% and for HHD ranged between 73 to 82%. Study 2 reliability study results: Intraclass correlation coefficients (ICC) were mixed but predominantly acceptable (ICC = 0.625 to 0.976). Coefficients of variation (CV) were acceptable on all occasions (1.59 to 10.91%). Correlation between the Biostrain and Kin Com were large to very large Kin Com (r = 0.495 to 0.851). Study 3 correlation study results: The back leg Biostrain data showed large to very large associations with 20 m sprint performance for the majority of time points (r = -0.505 to -0.763). Peak forces of the front leg mostly exhibited large correlations with sprint performance (r = 0.467 to -0.656). Study 1 systematic review conclusion: IKD was more reliable than HHD though it was clear that HHD and IKD has been assessed in a range of positions, angles and used different units of measurement making it difficult for between study comparisons to be made. Study 2 and 3 Conclusions: The Biostrain demonstrates strong reliability and validity coupled with substantial correlations with the gold standard IKD and sprint performance suggesting its potential as a tool for assessing isometric force time characteristics.

Key words: Hip extension; Hip Flexion, Knee flexion, Isometric, flight phase

Citation

Calderbank, J. (2024). Evaluation of a novel device to assess combined knee flexion and hip extension, and hip flexion force production capability. (Thesis). University of Salford

• Thesis Type: Thesis
• Deposit Date: May 10, 2024
• Publicly Available Date: Jul 1, 2024
• Keywords: Hip extension; Hip Flexion, Knee flexion, Isometric, flight phase
• Award Date: May 31, 2024