{"publication_id":"a7d2fa80-23dd-4c69-b863-df035c479906","screening":{"identified":85,"screened":85,"excluded":0,"included":85,"included_or_retained":85,"flow":["identified","screened","excluded_with_reasons","included"],"wording":"85 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":["Resistance training is widely promoted across the lifespan for preserving muscle mass, strength, mobility, and metabolic health, yet the empirical record on its effects remains heterogeneous, with positive, null, and negative signals co-existing across age groups and clinical populations.","We conducted an AI-assisted structured evidence synthesis with an explicit audit trail, organizing 85 curated primary studies and reviews by study design, outcome class, and directness, while keeping direct, indirect, and review-level evidence in separate tiers to avoid cross-domain conflation.","Across the corpus, the synthesis supports resistance training as a generally effective strategy for muscle strength and physical function in older adults, with effect sizes that are quantitatively meaningful even when they fall below the 0.1 m/s gait-speed threshold (Perera 2006), but the cardiometabolic, inflammatory, and bone endpoints remain too inconsistent across studies to support universal clinical claims.","The corpus contains 31 direct clinical sources, 53 adjacent, review, or context sources, and 1 mechanistic or model-system source. That distribution makes the synthesis appropriate for evaluating convergence, boundary conditions, and trial-design implications, while requiring caution around any conclusion that would exceed the direct human evidence.","Null findings have a specific role in this evidence model. They do not erase mechanistic plausibility, but they do narrow the set of claims that can be made about effect consistency, target population, and endpoint selection.","The evidence base also distinguishes breadth from certainty. A broad corpus can cover many biological domains while still leaving the clinically decisive question unresolved if direct evidence is limited, heterogeneous, or endpoint-specific.","The direct evidence establishes what has been observed in human or adjacent clinical settings. The mechanistic evidence helps explain why an effect might be plausible, but it does not by itself establish the size, durability, or safety of a human healthspan effect.","The study-level structure also prevents selective emphasis. Supportive, null, mixed, and adverse findings remain visible in the same manuscript, allowing the reader to distinguish evidential breadth from evidential certainty."]}