Simulação da eletrofisiologia do músculo esquelético: análise da contração muscular e da propagação elétrica

Abstract

The skeletal muscles are essential for movement and body stability. The simultaneous activation of motor unit fibers occurs when the motor neuron sends an electrical impulse, resulting in a uniform contraction of the fibers. Computational modeling of skeletal muscle electrophysiology enables a detailed analysis of muscle contraction and electrical propagation. In this study, two distinct experiments were implemented. In the first one, calcium dynamics and the Hodgkin-Huxley model were combined to describe the relationship between action potential and muscle contraction, evaluating the impact of multiple motor unit activation and bringing as an innovation the addition of the latency period, that is, the delay between the electrical stimulus and the generation of force, which resulted in a representation more faithful to physiological reality. In the second experiment, electrical propagation in skeletal muscle was simulated using a simplified version of the bidomain model, allowing the analysis of action potential transmission through muscle tissue. Both experiments were numerically solved using the finite difference method. The results indicated that the employed models are capable of representing the studied phenomena, providing a foundation for biomedical applications such as electromyography and the development of myoelectric devices.