Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Mar 31.
doi: 10.1113/EP092194. Online ahead of print.

Effects of neuromuscular electrical stimulation on voluntary muscle activation and peripheral muscle contractility following short-term bed rest

Sofie K Hansen  1   2 , Pernille Hansen  1   2 , Tania W Berry  1 , Hans D Grønbæk  1 , Camilla M Olsen  1 , Youssif Merhi  3 , Shweta Agarwala  3 , Per Aagaard  4 , Lars G Hvid  5   6 , Jakob Agergaard  7   8 , Flemming Dela  9   10 , Charlotte Suetta  1   2
Affiliations

Effects of neuromuscular electrical stimulation on voluntary muscle activation and peripheral muscle contractility following short-term bed rest

Sofie K Hansen et al. Exp Physiol. .

Abstract

Disuse induces a disproportionate loss of muscle force compared with muscle mass, with unclear effects on voluntary muscle activation (VA) and peripheral contractility. Furthermore, the effect of neuromuscular electrical stimulation (NMES) as a disuse countermeasure remains uncertain. We investigated the effects of NMES during bed rest on neuromechanical function to improve our understanding of the mechanisms underlying disuse-induced reductions in muscular force. Young (n = 16, 25 years old) and old (n = 16, 71 years old) adults underwent 5 days of bed rest. One leg received NMES (3 × 30 min/day), while the other served as the control (CON). Maximal isometric knee-extensor strength (MVIC), VA and peripheral muscle contractility were assessed before and after bed rest using the interpolated twitch technique, along with biomarkers of neuromuscular junction instability (C-terminal agrin fragment (CAF)) and muscle damage (creatine kinase (CK)). MVIC decreased in both age groups, regardless of NMES (young: CON, -21.7 Nm and NMES, -23.8 Nm; old: CON, -18.5 Nm and NMES, -16.4 Nm). VA was preserved with NMES, while decreasing in CON legs (young, -8.1%; old, -5.6%) following bed rest. Peripheral contractility (resting doublet twitch force) was reduced in CON and NMES legs in both age groups (young: CON, -4.0 Nm and NMES, -11.5 Nm; old: CON, -5.9 Nm and NMES, -10.8 Nm), with a greater decrease in NMES legs. CAF remained unchanged, whereas CK levels increased in young participants, albeit remaining within the normal range. In conclusion, a decline in neuromechanical function was observed after 5 days of bed rest in young and old adults. Although NMES appeared to preserve VA, peripheral muscle contractility was altered, resulting in reduced MVIC.

Keywords: bed rest; central activation; muscle contractile properties; muscle function; neuromuscular electrical stimulation; neuromuscular junction stability.

PubMed Disclaimer

References

REFERENCES

    1. Aagaard, P. (2003). Training‐induced changes in neural function. Exercise and Sport Sciences Reviews, 31(2), 61–67.
    1. Bickel, C. S., Gregory, C. M., & Dean, J. C. (2011). Motor unit recruitment during neuromuscular electrical stimulation: A critical appraisal. European Journal of Applied Physiology, 111(10), 2399–2407.
    1. Campbell, M., Varley‐Campbell, J., Fulford, J., Taylor, B., Mileva, K. N., & Bowtell, J. L. (2019). Effect of immobilisation on neuromuscular function in vivo in humans: A systematic review. Sports Medicine, 49(6), 931–950.
    1. Cattagni, T., Lepers, R., & Maffiuletti, N. A. (2018). Effects of neuromuscular electrical stimulation on contralateral quadriceps function. Journal of Electromyography and Kinesiology, 38, 111–118.
    1. Coker, R. H., Hays, N. P., Williams, R. H., Wolfe, R. R., & Evans, W. J. (2015). Bed rest promotes reductions in walking speed, functional parameters, and aerobic fitness in older, healthy adults. Journals of Gerontology—Series A Biological Sciences and Medical Sciences, 70(1), 91–96.

LinkOut - more resources