Rethinking sarcopenia: a conceptual shift towards a muscle health continuum

Current guideline-based approaches to sarcopenia are operationalised around thresholds of muscle mass, strength, and performance, which limit the opportunities for early/preventive intervention. This view insufficiently reflects skeletal muscle as a multifunctional organ and fails to capture its dynamic and heterogeneous nature. The objective of this manuscript is to place sarcopenia within this muscle health continuum.

Expert discussions were conducted to identify conceptual limitations in existing approaches and to explore opportunities for improvement. These discussions were complemented by a narrative review of the literature, forming an integrative conceptual framework.

A six-stage muscle health continuum is proposed in which sarcopenia is positioned as an advanced, pathological state rather than a binary diagnosis. Conceptual definitions of muscle health and muscle failure are introduced, alongside causal factors as potential targets for treatment as well as an aetiological stratification into subtypes. The framework is aligned with the International Classification of Functioning, Disability and Health to contextualise muscle dysfunction in terms of functioning and disability. To enhance diagnostic resolution and treatment monitoring, the concept of muscle profile analysis is introduced, supporting the use of direct muscle visualisation techniques such as ultrasound, computed tomography, and magnetic resonance imaging.

Positioning sarcopenia within a broader muscle health continuum reframes it from a late-stage geriatric diagnosis into a condition embedded within a lifelong trajectory. This conceptual shift hopes to kindle discussions about earlier assessment, preventive strategies, and individualised interventions, laying the foundation for future research, clinical innovation, and guideline evolution aimed at improving patient outcomes.