22 October 2025
Bilbao Campus
Under the title ‘Muscle quality in aging: analysis of noninvasive diagnostic methods, from morphological to functional approach, for routine community implementation and identification of key factors for an exercise protocol to enhance muscle quality’, researcher Naiara Virto Castro defended her doctoral thesis at the University of Deusto, analysing and shedding light on how to change the way sarcopenia is assessed and improve its diagnosis.
Supervised by Begoña García Zapirain and Amaia Méndez, the research — aligned with international and national public health and healthy ageing promotion strategies, such as those of the World Health Organization (WHO), the national Frailty Roadmap, and the Basque Country Science, Technology and Innovation Plan (PCTI) — is set within the current context of population ageing. A context in which the increase in life expectancy is a success story of modern society, but at the same time poses important challenges that make it necessary to reform social and health systems to respond to the demands of the new population paradigm.
Sarcopenia is the progressive loss of muscle mass and function that often threatens independence in old age. In her study, the researcher highlights the importance of considering muscle quality (MQ) when identifying potential risks of sarcopenia or dependency, a concept that refers not only to muscle mass but also to its function and efficiency. The research shows that, at present, its assessment remains an emerging field, with diagnostic tools still under development, which makes clinical and community implementation challenging.
How to measure muscle quality
To change this situation and facilitate the diagnosis of the condition, this research proposes methods for assessing and treating muscle quality in older adults, aiming for an appropriate balance between accessibility, cost, and accuracy, depending on the context in which they are applied. In this regard, the thesis highlights that advanced methods such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) are accurate but expensive and not widely accessible.
Ultrasound, however, emerges as a promising, accessible, and radiation-free tool, though it requires further standardisation for widespread use. Therefore, the study considers functional methods, based on the relationship between muscle strength and muscle mass, as the most viable option. These methods are simple, practical for routine medical practice, and do not require complex equipment or costly procedures.
The thesis emphasises that assessing muscle quality requires more than measuring mass; it is also necessary to consider the loss of muscle power, as this is one of the most important predictors of sarcopenia. Other key determinants include strength and balance, which are essential for functionality; biological factors, such as advanced age, sex, and body mass index (BMI), which influence the risk of developing sarcopenia; and social factors, including socioeconomic status. Moreover, the study emphasises that walking speed is a non-invasive vital sign reflecting functional status and neuromuscular integrity in older adults.
The research also proposes an evidence-based, personalised exercise protocol for people aged 60 and over, with a central focus on strength and power training, since the decline in muscle power precedes the loss of strength and muscle mass during ageing. The recommended protocol includes resistance training with moderate to high loads, avoiding muscular fatigue, to improve strength and maintain independence; power training based on quick actions with moderate loads to enhance functional capacity; balance and gait exercises with progressive challenges that also incorporate cognitive tasks; and, finally, aerobic training, introduced once basic strength has been established.
