Neuromuscular component of muscle quality assessment in older adults: Narrative review

Katarina Puš; Boštjan Šimunič

doi:10.52165/kinsi.30.1.95-111

Authors

Katarina Puš Science and Research Center Koper, Institute for Kinesiology Research, Koper, Slovenia
Boštjan Šimunič Science and Research Center Koper, Institute for Kinesiology Research, Koper, Slovenia https://orcid.org/0000-0003-1565-7833

DOI:

https://doi.org/10.52165/kinsi.30.1.95-111

Keywords:

ageing, skeletal muscle, ultrasound sarcopenia index, phase angle, muscle quality index

Abstract

The concept of muscle quality encompasses both micro- and macroscopic aspects of muscle architecture and composition and has gained increasing attention with inclusion in the definition of sarcopenia, indicating the significance of muscle quality in evaluating muscle function and strength among older individuals. Muscle quality consists of two main components: neuromuscular and morphological and is often defined as the ratio between the two. The aim of this review is to present currently used methods for assessment of muscle quality with an emphasis on neuromuscular component in older adults. The most used methods for assessing morphological component are imaging techniques, such as magnetic resonance imaging, computed tomography, dual-energy X-ray absorptiometry and non-imaging bioimpedance analysis. In the neuromuscular component upper and lower body strength are assessed with different methods such as hand grip strength, isokinetic lower limb strength and isometric lower limb strength. Currently, there are three proposed muscle quality assessment methods for field or population studies: muscle quality index, ultrasound sarcopenia index and bioimpedance-derived phase angle. Despite the exploration of muscle quality through various assessment methods, a consensus on the most appropriate and universally applicable approach has yet to be established.

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References

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