{"publication_id":"d1ef7738-dd48-43f0-9c62-4e9211efdff2","screening":{"identified":31,"screened":31,"excluded":0,"included":31,"included_or_retained":31,"flow":["identified","screened","excluded_with_reasons","included"],"wording":"31 candidate receipts retained after source retrieval, deduplication, and topic filtering. This is an evidence-map screening trace, not a PRISMA full-text exclusion audit.","exclusion_reasons":["No PRISMA full-text exclusion-stage filter was applied."]},"limitations":["This is an agent-assisted evidence map, not a PRISMA-complete systematic review or clinical guideline.","It is not PROSPERO-registered and should not be read as medical advice.","Public sidecars expose citation traces and extraction status; empty fields mean not extracted, not assumed absent."],"contradictions":["However, the evidence base is characterized by significant tension, as many interventions aimed at improving gait speed show mixed or null effects on underlying frailty, a key longevity intermediate.","The evidence profile indicates that while slower gait speed is a robust independent predictor of mortality and morbidity across diverse populations, the current evidence is not consistent with that improving gait speed alone extends lifespan.","Gait speed has been proposed as a powerful, integrative biomarker of physiological reserve in aging, yet the central question of whether gait speed longevity represents a causal target or merely a downstream epiphenomenon of healthier aging remains unresolved. The aging global population faces a dual crisis: rising chronic disease burden and a search for scalable, low-cost interventions that extend healthspan, not just lifespan. A walking speed threshold of 0.8 m/s has been widely associated with impaired mobility and frailty risk (Studenski 2011), and more severe limitations fall below 0.6 m/s (Cesari 2009). These thresholds are not merely statistical artifacts; they correlate with disability, hospitalization, and mortality across dozens of cohorts. The clinical stakes of gait speed longevity research are therefore high, as even modest improvements of 0.1 m/s may mark a clinically meaningful functional change (Perera 2006). Annual age-related decline in gait speed among older adults approximates 0.05 m/s (Bohannon 1997), meaning that interventions capable of slowing or reversing this trajectory could, in principle, delay the onset of mobility dependence. It is in this context of population aging, rising healthcare costs, and the search for measurable geriatric outcomes that gait speed longevity has attracted intense research attention. However, the field must grapple with whether observed associations truly reflect a modifiable causal pathway or are confounded by residual health status.","The geroscience hypothesis posits that targeting fundamental biological hallmarks of aging — such as cellular senescence, mitochondrial dysfunction, and chronic inflammation — should simultaneously delay or prevent multiple age-related diseases. Within this framework, gait speed longevity has been proposed as an accessible functional readout that may integrate the cumulative effects of these hallmarks on the musculoskeletal, nervous, and cardiovascular systems. If gait speed reflects systemic biological aging, then interventions that modulate aging biology should improve gait performance as a downstream marker. This logic has motivated the repurposing of existing drugs, such as metformin and NAD+ precursors, whose primary indications lie elsewhere but whose mechanisms appear to intersect with aging pathways. Alternatively, novel agents specifically designed to target aging biology may also yield gait speed improvements, though the pipeline remains largely preclinical. The appeal of repurposing lies in the existing safety and pharmacokinetic data for approved compounds, yet the evidence for gait speed longevity as a hard endpoint remains sparse compared to traditional cardiovascular or metabolic endpoints. It has been suggested that gait speed may function as a composite biomarker of geroscience target engagement, but this claim requires rigorous testing in dedicated aging-focused trials. The question of whether gait speed longevity truly indexes the rate of biological aging, or merely the presence of subclinical disease, is central to validating this hypothesis.","Among the candidate interventions for gait speed longevity, the evidence base is heterogeneous and, at times, contradictory. A key concern is that gait speed is highly sensitive to contextual factors — including pain, cognition, medication burden, and environmental conditions — that may confound any drug-outcome relationship. This finding stands in tension with the cardioprotective rationale for statin use, and it underscores the complexity of attributing gait speed changes to any single pharmacological mechanism. Conversely, Mone 2025 observed that patients with heart failure with preserved ejection fraction (HFpEF) and elevated stress hyperglycemia ratios demonstrated significantly reduced physical performance, including a mean gait speed of 0.65 ± 0.20 m/s, linking metabolic dysregulation to mobility impairment. These observational findings suggest that gait speed longevity may be modulated by systemic metabolic health, yet the causal direction remains uncertain. The regulatory landscape for aging interventions has not yet established gait speed as a primary endpoint for drug approval, further complicating translation from bench to bedside. It appears that the field is at an inflection point: mechanistic plausibility is high, but the human trial evidence needed to support gait speed longevity as a clinical target is still emerging.","The human RCT landscape for interventions targeting gait speed longevity encompasses a diverse array of study designs, endpoints, and population characteristics, but no single trial has definitively established causality. Pan 2025 evaluated a multicomponent Otago Exercise Program combined with resistance training in pre-frail nursing home residents, demonstrating improvements in physical function over 12 weeks, though the primary focus was sarcopenia rather than gait speed alone. Rice 2025 examined home-based exercise in older adults with a previous fall, finding that baseline gait speed modified intervention efficacy — with slower walkers (<0.80 m/s) exhibiting differential fall-rate outcomes at 6 and 12 months. This stratification highlights a critical issue: gait speed longevity interventions may have heterogeneous effects depending on baseline functional status. OlasoGonzalez 2026, a mechanistic RCT, reported that a multidomain lifestyle intervention was associated with improved functional trajectories and favorable changes in epigenetic aging markers in frail older adults (mean age ~80 years), with statistically significant improvements across multiple endpoints (P < 0.0001). The inclusion of epigenetic clocks as endpoints represents an important advance, linking gait speed longevity directly to biological aging measures. However, the small sample size (n = 19 per group in the control arm) and short follow-up limit generalizability. Karim 2026 tested multi-strain probiotics on frailty in osteoarthritis patients, demonstrating reduced frailty scores and improved walking-related pain (P < 0.05), suggesting that non-pharmacological and microbiome-targeted approaches may also influence gait speed longevity. Across the corpus, these trials reflect a field in which intervention heterogeneity, population diversity, and endpoint variability make cross-study comparison challenging.","This synthesis contributes a structured, evidence-weighted evaluation of the Gait speed longevity literature that separates clinical outcomes from mechanistic insights. Across the curated evidence base, positive signals for gait speed longevity appear in frailty and contextual outcome domains, while negative and null findings also cluster in these same categories — reflecting the cross-study disagreements identified in the accompanying cross-study disagreement map. Similarly, Li 2026 found that physical frailty predicted postoperative complications and cognitive impairment in liver cancer patients, with frailty criteria count associated with increased risk (OR = 2.07 [95% CI 1.14–3.75]; P = 0.01), but this does not demonstrate that gait speed-targeted interventions can mitigate surgical risk. The synthesis reveals that the Gait speed longevity anti-aging case, as currently constituted, is incomplete: mechanistic plausibility coexists with mixed or sparse human-RCT evidence, and the boundary conditions remain to be established. Future research must address cross-outcome tensions through head-to-head trials, standardized gait speed measurement protocols, and inclusion of both surrogate and hard endpoints. The question of whether gait speed longevity represents a true causal target for aging interventions, or a convenient but ultimately non-specific marker, will only be resolved through this rigorous, structured approach.","Preclinical and mechanistic investigations provide a plausible biological foundation for the Gait speed longevity association, though the evidence remains largely observational and indirect in humans. Walking performance integrates multiple physiological domains — skeletal muscle contractile function, mitochondrial oxidative phosphorylation, central motor planning, peripheral nerve conduction, and cardiopulmonary reserve — suggesting that gait speed may serve as a proxy for systemic biological integrity. In the Fried frailty phenotype, gait speed is one of five cardinal criteria, and its impairment signals accelerated biological aging across interconnected pathways including inflammation, sarcopenia, and metabolic dysregulation. Furthermore, depression has been shown to mediate the association between frailty and motoric cognitive risk syndrome, illustrating the bidirectional interplay between psychological and motor domains in the Gait speed longevity construct (Li 2026b, P < 0.001). However, the causal directionality of these associations remains uncertain, as most preclinical models cannot fully recapitulate the complexity of human walking, and the translation from mechanistic biomarkers to hard longevity endpoints requires further validation (Ioannidis 2005).","The clinical-trial landscape for interventions targeting gait speed in the context of longevity is characterized by small mechanistic studies, heterogeneous populations, and varying intervention durations, with no large-scale hard-outcome trial yet completed. Multicomponent exercise programs, including the Otago Exercise Program combined with resistance training, have demonstrated efficacy in pre-frail nursing home residents over 12-week interventions, with significant improvements in body composition and physical function (Pan 2025, P < 0.001). Resistance training modality matters for frailty outcomes, with high-speed resistance training preserving one-leg stand performance over 16 weeks while low-speed training showed performance reductions (Coelho-Junior 2021, P = 0.01), suggesting that movement velocity during training may differentially engage gait-speed-relevant neuromuscular pathways. Exergaming incorporating a resistance component has been explored as an alternative to traditional resistance training in pre-frail and frail nursing home residents, though the evidence remains preliminary (Liu 2026). Protein supplementation combined with resistance training has been evaluated in a systematic review and meta-analysis for gait speed outcomes in older adults (Li 2024), yet the overall clinical-trial landscape suffers from small sample sizes, short durations, and the absence of mortality or longevity-specific endpoints.","Methodological challenges pervade the Gait speed longevity literature and constrain the strength of causal inference that can be drawn from the existing evidence. Endpoint selection remains contentious: usual gait speed, fast gait speed, gait speed reserve, dual-task gait speed, and community walking speed each capture distinct aspects of locomotor capacity, and their measurement properties vary across populations (Mehdipour 2024). A clinically meaningful change threshold of 0.1 m/s (Perera 2006) has been widely adopted, yet the sensitivity and specificity of this threshold for detecting meaningful longevity-relevant change has not been systematically validated across all clinical contexts. Heterogeneity in study populations — spanning community-dwelling older adults, nursing home residents, cancer patients, hemodialysis patients, and hemiplegia patients — complicates meta-analytic synthesis and limits the generalizability of pooled effect estimates. The mechanism-to-clinic gap is pronounced: while gait speed plausibly reflects mitochondrial function, sarcopenia, neuroinflammation, and cardiovascular reserve, few trials have simultaneously measured mechanistic biomarkers and hard clinical endpoints, leaving surrogate-endpoint validity uncertain (Ioannidis 2005). Treatment duration in existing trials ranges from 3 to 16 weeks, far shorter than the multi-year follow-up periods needed to ascertain longevity effects, and attrition rates in long-duration RCTs of older adults typically approach 20% (Schulz 2010), threatening both statistical power and external validity. Concurrent interventions — including polypharmacy, nutritional supplementation, and psychosocial support — create confounding pathways that are difficult to disentangle from the direct effects of gait-speed-targeted therapies. Ultimately, resolving these methodological challenges will require large-scale, long-duration RCTs with pre-specified gait speed endpoints, mechanistic biomarker substudies, and adjudicated hard outcomes including all-cause mortality.","Quantitatively, the evidence presents a mixed profile within this class. The specific p-values from each study's analysis are detailed in the evidence synthesis.","A within-corpus tension exists between the mechanistic expectation and the clinical RCT evidence. The mechanistic substrate for a gait-cognition link remains biologically plausible, supported by broader literature on frailty and aging. However, the curated evidence from Mirzai 2025, a high-quality secondary analysis of a major RCT, found a null association. This tension underscores that the boundary conditions for gait speed as a cognitive predictor require further establishment, particularly regarding the influence of specific patient populations and comorbidity management.","The corpus includes 16 studies examining the relationship between gait speed and frailty outcomes, spanning observational cohorts, systematic reviews, and one clinical RCT. Populations ranged from community-dwelling older adults to patients with hematologic malignancies, cancer, hemodialysis, and Parkinson's disease. Study designs were predominantly observational cohorts, with several systematic reviews and meta-analyses providing synthesis-level evidence. The sole clinical RCT (Karim 2026) examined multi-strain probiotic supplementation in osteoarthritis patients, while other intervention-focused studies assessed digital health approaches (Dai 2026) and protein supplementation combined with resistance training (Li 2024). Gait speed was measured using various protocols including usual gait speed, fast gait speed, and dual-task walking conditions."]}