Design, Fabrication, and Experimental Validation of a Low-cost Neuromuscular Electrical Stimulator for the Prevention of Skeletal Muscle Atrophy

Abstract

Individuals with limited mobility are at a significantly higher risk of muscle atrophy due to prolonged sedentary states. In rural Nigeria, the inconsistent electrical supply often renders contemporary electrical muscle stimulators (EMS) redundant. To address this, the current study aims to design and fabricate and experimentally validate a low cost, battery-powered muscle stimulator that ensures readily available therapy in resource-constrained environments. A user-centered design approach was adopted, involving the construction of a portable power management unit and a muscle stimulation circuit. The system’s output parameters were verified using Proteus 8 simulation software to ensure voltage and current ranges aligned with established clinical standards. The hardware features an LCD interface that displays real-time frequency and stimulation duration. To evaluate clinical efficacy, handgrip strength gains were measured using a dynamometer and compared against a standard commercial EMS unit. The test was approved by the ethics committee of the Federal University of Science and Technology, Owerri. Nigeria. A paired-sample t-test conducted on 30 young adults between ages 18 – 30 revealed that the mean strength gain for the fabricated system (3.995 ± 0.483) did not differ significantly from the standardized EMS (3.947 ± 0.782), with t (29) = 0.516 and p = 0.610 (two-tailed). Furthermore, a strong positive correlation (r = 0.7899) indicated highly similar response patterns between the two modalities. These results demonstrate that the low-cost, battery-operated stimulator is a viable, high-performance alternative for muscle rehabilitation in areas lacking stable power infrastructure.