Development of a Coaching System for Functional Electrical Stimulation Rowing: A Feasibility Study in Able-Bodied Individuals.

Shirin Tajali,Kai Lon Fok,Kei Masani,Hikaru Yokoyama,Pirashanth Theventhiran,Kento Nakagawa,Gongkai Ye

doi:10.3390/s22051813

Abstract

Background: Functional electrical stimulation (FES) during rowing has substantial effects on cardiovascular health in individuals with spinal cord injuries. Currently, manual stimulation control where stimulation is operated by rowers is mostly utilized. However, it takes time to obtain the skill to initiate FES at the optimal timing. The purpose of this study was to develop a coaching system that helps rowers to initiate FES at the optimal timing. Methods: The optimal range for FES application was identified based on the electromyography of the left quadriceps in 10 able-bodied individuals (AB). Then, the effects of the coaching system on the timing of button-pressing, power, and work were investigated in 7 AB. Results: Vastus lateralis (VL) activation began consistently before the seat reached the anterior-most position. Therefore, seat position at the onset of VL was used as the variable to control the switch timing in the coaching system. The results revealed significantly higher power and work outputs in the coaching than the no-coaching condition (median power coaching: 19.10 W, power no-coaching: 16.48 W, p = 0.031; median work coaching: 109.74 J, work no-coaching: 65.25 J, p = 0.047). Conclusions: The coaching system can provide the optimal timing for FES, resulting in improved performance.

Highlights

Spinal cord injuries (SCI) affect around 500,000 individuals per year around the world [1]
We mainly focused on the EMG activation of knee extensor muscles including the Vastus lateralis (VL), vastus medialis (VM) and rectus femoris (RF)
To guide the timing of the manual button-pressing for administering functional electrical stimulation (FES), seat position at the onset of VL activation was used

Summary

Introduction

Spinal cord injuries (SCI) affect around 500,000 individuals per year around the world [1]. Due to muscle paralysis, exercises are typically restricted to the upper body, such as arm crank ergometry and weight training [5,6] These exercises have limited ability to produce the high exercise intensity required for cardiovascular adaptation, as only a small amount of muscle mass is typically involved [3,7]. One possible solution to increase exercise intensity and enhance cardiovascular performance is through functional electrical stimulation (FES) assisted exercise [7–9]. Functional electrical stimulation (FES) during rowing has substantial effects on cardiovascular health in individuals with spinal cord injuries. The purpose of this study was to develop a coaching system that helps rowers to initiate FES at the optimal timing. Conclusions: The coaching system can provide the optimal timing for FES, resulting in improved performance

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Discussion

Conclusion