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Updated: Jan 3, 2026

A Murine Model of Muscle Training by Neuromuscular Electrical Stimulation
Published on: May 9, 2012
The Effect of Electrical Muscle Stimulation and In-bed Cycling on Muscle Strength and Mass of Mechanically Ventilated
Kyeongyoon Woo1, Jeongmin Kim1, Hye Bin Kim1
1Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea.
Background:
Critically ill patients experience muscle weakness, which leads to functional disability. Both functional electrical stimulation (FES) and in-bed cycling can be an alternative measure for intensive care unit (ICU) patients who are not feasible for active exercise. The aim of this study was to examine whether FES and in-bed cycling have a positive effect on muscle mass in ICU patients.
Methods:
Critically ill patients who received mechanical ventilation for at least 24 hours were included. After passive range of motion exercise, in-bed cycling was applied for 20 minutes, and FES was applied for 20 minutes on the left leg. The right leg received in-bed cycling and the left leg received both FES and in-bed cycling. Thigh circumferences and rectus femoris cross-sectional area (CSA) were assessed with ultrasonography before and after the intervention. Muscle strength was assessed by Medical Research Council scale.
Results:
A total of 10 patients were enrolled in this study as a pilot study. Before and after the intervention, the CSA of right rectus femoris increased from 5.08 ± 1.51 cm2 to 6.01 ± 2.21 cm2 , which was statistically significant (P = 0.003). The thigh circumference was also increased and statistically significant (P = 0.006). There was no difference between left and right in regard to FES application. There is no significant change in muscle strength before and after the intervention (right and left, P = 0.317 and P = 0.368, respectively).
Conclusions:
In-bed cycling increased thigh circumferences rectus femoris CSA. Adding FES did not show differences.
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