Comparative analysis of knee extensor neuromuscular function between 13- to 15-year-old strength- and endurance-trained children, and untrained children

• Grant number: 22/13273-4
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: April 01, 2023
• End date: June 30, 2023
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Ana Cláudia Mattiello-Sverzut
• Grantee: Ester da Silva Estevam
• Supervisor: Sebastien Ratel
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: Université Clermont Auvergne (UCA), France
• Associated to the scholarship: 22/01644-8 - Peripheral muscular fatigue of upper limbs in children and adolescents with neuromuscular diseases: assessment by the handgrip dynamometer (bulb), BP.IC

Abstract

Skeletal muscles can adapt to the different constraints imposed by the environment due to the phenomenon called muscle plasticity. In healthy people and those with chronic morbidity, the aim is to increase motor functions and skills through training protocols to increase muscle strength or endurance. Strength training consists of using different types of resistive load and various training modalities, repeated for an extended period and sufficient to induce physiological adaptations. By evaluating the maximal voluntary isometric torque and electromyographic activity, it is possible to analyze the level of muscle activity and, more generally, muscle function. Thus, the objective of the present project is to compare the neuromuscular profile of the knee extensors (maximal voluntary isometric torque, electromyographic activity, voluntary activation level, and muscle architecture) between 13- to 15-year-old strength-trained children, endurance-trained children, and untrained children. The data from endurance-trained and untrained children were previously collected/analyzed. The objective will be to recruit and test fifteen strength-trained children for comparison with the two former groups. For the neuromuscular assessment, the maximal voluntary isometric torque of the knee flexor and extensor muscles will be measured using an isokinetic dynamometer (Cybex NORM; Lumex, Ronkonkoma, NY). The peripheral magnetic stimulation of the femoral nerve and electromyographic measurements of vastus lateralis, rectus femoris, and biceps femoris will determine voluntary activation and muscle contractile properties. In addition, muscle architecture will be defined using muscle ultrasound. (AU)