Resilience as recovery: stakeholder perspectives on Uganda's health system response to infectious disease shocks.

Habitual physical activity (PA) is a fundamental determinant of health, contributing to the prevention and management of multiple chronic conditions, including cardiovascular disease, type 2 diabetes, selected cancers, and poor mental health outcomes [–]. Reflecting this robust evidence base, global PA guidelines for the general population consistently emphasise that engaging in PA is preferable to doing none, underscoring that all movement has health value [–]. While guidelines typically specify recommended volumes of moderate-to-vigorous physical activity (MVPA)—activities that raise heart rate and breathing such as brisk walking or cycling—they also explicitly acknowledge that meaningful health benefits accrue even below these thresholds. For many population groups, including older adults, people living with long-term conditions or disabilities, individuals with chronic pain, frailty, or low baseline fitness, and those recovering from illness, the primary goal is not necessarily achieving MVPA targets but increasing any form of PA according to individual capability []. In these contexts, light-intensity activities, incidental movement, and reductions in sedentary time are clinically and socially meaningful [], reinforcing a more inclusive, pragmatic framing of PA that extends beyond structured exercise []. Despite this central importance, the assessment and reporting of habitual PA vary substantially across research studies []. Systematic reviews that seek to synthesise habitual PA outcomes are therefore frequently challenged by heterogeneity in measurement tools, implementation protocols, outcome metrics, and reporting practices; for example, heterogeneity in methods and reporting has been so extensive that meta-analysis was impossible in a review of habitual PA in people with cognitive impairment []. Such heterogeneity often reflects differences in the study aims, behavioural targets, and conceptualisations of PA of the studies assessed for inclusion in the review and does not necessarily imply methodological shortcomings of those studies. PA measurement is inherently purpose-driven, and while habitual PA spans all daily domains and intensities many primary studies target specific PA behaviours (e.g., structured exercise, walking, or MVPA). In such cases, measurement approaches that focus narrowly on a specific intensity, modality, or context may be entirely appropriate for the study aim, even if they do not capture habitual PA in its broadest sense. Distinguishing between fit-for-purpose measurement and comprehensive assessment of habitual PA is therefore essential when interpreting measurement choices across studies. Figure presents a conceptual framework illustrating this distinction and the intended scope of the proposed screening tool.