Healthy Ageing: Measuring and Maintaining Functional Ability

Digital health interventions are increasingly being explored to support healthy ageing. This interest comes against a backdrop of increasing pressure on health care systems, including projected workforce shortages (2). Eberle et al. (this issue) propose a digital platform combining nutrition, learning, exercise and social participation as a prevention-focused approach alongside disease-oriented digital health applications. Whether such a platform can change health-related behaviour remains to be demonstrated. Wearable technologies may complement episodic clinical assessment by providing longitudinal information on mobility and other behavioural and physiological changes in real-world settings (1). Beyond monitoring function over time, however, understanding age-related decline also requires more detailed assessment of its underlying mechanisms. In the context of sarcopenia, Gennaro et al. (this issue) propose reframing sarcopenia partly as a disorder of brain-muscle communication. They integrate corticospinal connectivity, motor-unit behaviour and muscle synergies into a multimodal framework and argue that dynamic and ecologically valid tasks may better capture neural contributions to muscle weakness. The framework remains hypothesis-generating and requires validation.

Together, these contributions illustrate that healthy ageing requires a continuum of assessment, targeted intervention and sustained support rather than a single solution. They span the identification of functional limitations, exercise-based approaches to improve functional capacity, prevention-oriented digital support and a refined assessment of age-related neuromuscular decline.
The common agenda is therefore not more technology, but better matched assessment, technology and intervention. Researchers and clinicians need to determine which approaches are appropriate, for whom, under what conditions, and with what level of support. A device or digital intervention suitable 
for a physically and cognitively fit 65-year-old may not be suitable for a frail 85-year-old living in residential care. Intervention type and dose should be tailored to baseline capacity rather than applying a one-size-fits-all approach. Functional gains can occur without parallel increases in daily activity. Whether functional gains translate into sustained increases in daily physical activity may depend on longer follow-up and continued behavioural and environmental support. Digital platforms could provide one form of such support, but sustained engagement with these platforms and their effectiveness remain to be established. Novel assessment tools also require validation against clinically meaningful outcomes and established assessments before they inform routine practice.

These advances require policy support, but implementation should follow evidence. A long-observed consequence of the global epidemiologic shift is, for example, the rise in non-communicable diseases that lead to sizeable increases in disability-adjusted life-years (6). This rising burden necessitates intensified efforts to mitigate exposure to leading risk factors and should include policies that, amongst others, promote physical activity (6). Healthcare systems should invest in the research and infrastructure needed to evaluate exercise-based prevention, digital platforms and longitudinal functional monitoring at scale. Likewise, reimbursement pathways should prioritise approaches that demonstrate effectiveness, clinical utility, accessibility and cost-effectiveness. Where effectiveness and utility are demonstrated, exercise-based frailty prevention and validated functional monitoring should be integrated across community, primary care, and long-term care settings, helping to translate healthy ageing from a policy goal into everyday practice. 
Ultimately, healthy ageing is not defined by the absence of disease, but by preserving the ability to remain active, independent and engaged in later life. The contributions in this issue highlight complementary approaches towards this goal: identifying functional limitations, improving physical capacity, supporting health-oriented behaviour and refining the assessment of age-related decline. Their common message is that effective strategies must consider the individual, be feasible in everyday life, and, above all, be supported by evidence.