Prediction of lower limb joint stiffness and optimization of anthropometric parameters in countermovement jump using an anthropometry-informed neural network
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引用次数: 0
Abstract
Background
The Countermovement Jump (CMJ) test, widely used to assess athletes' musculoskeletal and neuromuscular readiness, hinges on the performance of the hip, knee, and ankle joints. Despite extensive research, there is no consensus on which joint is most critical for CMJ performance. This study aims to identify the primary lower limb joint contributing to CMJ execution by analyzing maximum energy production and peak stiffness. Additionally, a novel neural network model was developed to predict joint stiffness during CMJ based on jump height and detailed anthropometric parameters, including body fat mass, lower body mass, upper body mass, and skeletal muscle mass ratios. Finally, a genetic algorithm was employed to optimize these parameters, maximizing joint stiffness and energy output.
Methods
Twelve male athletes performed CMJs, with data cleaning applied to their trials. Energy production and stiffness of the hip, knee, and ankle joints were calculated. The neural network, trained on joint stiffness data, facilitated two optimization problems solved via a genetic algorithm to determine optimal anthropometric parameters for maximizing joint peak stiffness and energy.
Findings
The hip joint was identified as the primary energy contributor (4.75 ± 1.71 J/kg), while the knee exhibited the highest peak stiffness (0.37 ± 0.04 N.m/°kg). The knee outperformed the hip (0.29 ± 0.02 N.m/°kg) and ankle (0.25 ± 0.04 N.m/°kg) in stiffness.
Interpretation
The hip generates the most energy during CMJ, while knee stiffness is crucial. Jump height, body fat, and skeletal muscle mass ratios significantly influence joint stiffness.
期刊介绍:
Clinical Biomechanics is an international multidisciplinary journal of biomechanics with a focus on medical and clinical applications of new knowledge in the field.
The science of biomechanics helps explain the causes of cell, tissue, organ and body system disorders, and supports clinicians in the diagnosis, prognosis and evaluation of treatment methods and technologies. Clinical Biomechanics aims to strengthen the links between laboratory and clinic by publishing cutting-edge biomechanics research which helps to explain the causes of injury and disease, and which provides evidence contributing to improved clinical management.
A rigorous peer review system is employed and every attempt is made to process and publish top-quality papers promptly.
Clinical Biomechanics explores all facets of body system, organ, tissue and cell biomechanics, with an emphasis on medical and clinical applications of the basic science aspects. The role of basic science is therefore recognized in a medical or clinical context. The readership of the journal closely reflects its multi-disciplinary contents, being a balance of scientists, engineers and clinicians.
The contents are in the form of research papers, brief reports, review papers and correspondence, whilst special interest issues and supplements are published from time to time.
Disciplines covered include biomechanics and mechanobiology at all scales, bioengineering and use of tissue engineering and biomaterials for clinical applications, biophysics, as well as biomechanical aspects of medical robotics, ergonomics, physical and occupational therapeutics and rehabilitation.