{"publication_id":"b09d87ba-d35f-4c9b-aeba-4d2cca7e8d21","content_hash":"sha256:c92b1ed49bc8713d74c39c1d72cdc41bf835f0ca83ac5faffa1aa2cf1b8983d2","nodes":[{"id":"b09d87ba-d35f-4c9b-aeba-4d2cca7e8d21","type":"publication","title":"collagen"},{"id":"claim_1","type":"claim","text":"Two receipts describe collagen-related metrics that move in different directions depending on the perturbation. The 1975 rat study reports that aging increases the **insoluble collagen fraction** and decreases the **salt-extractable collagen fraction** in red, white, and cardiac muscle. The 2010 human resistance-exercise study reports that intramuscular **collagen fractional synthesis rate (FSR)** is evenly elevated after both light-load and heavy-load knee-extension exercise and is **not affected by feeding**, while **myofibrillar FSR** responds only to heavy load and is further increased by feeding."},{"id":"claim_2","type":"claim","text":"These two receipts are **not directly comparable** because they use different metric types (collagen fraction composition vs. collagen FSR), different species (rat vs. human), and different timescales (chronic aging vs. acute post-exercise). Treated as an inference only, they suggest a boundary condition: the **same \"collagen\" label can carry opposite-direction signals** depending on whether the perturbation acts on collagen quality/composition (aging: more crosslinked/insoluble, less soluble) or on collagen turnover (acute exercise: FSR up regardless of load or feed)."},{"id":"claim_3","type":"claim","text":"Evidence that light-load and heavy-load resistance exercise differentially alter collagen FSR."},{"id":"source_1","type":"source","study":"Collagen in aging muscles.","year":1975,"doi":"10.1007/bf02326782","url":"https://doi.org/10.1007/bf02326782","population":"not extracted","intervention_or_exposure":"not extracted","comparator":"not extracted","endpoint":"not extracted","effect":"not extracted","risk_of_bias":"not appraised in public sidecar","directness":"primary"},{"id":"source_2","type":"source","study":"Contraction intensity and feeding affect collagen and myofibrillar protein synthesis rates differently in human skeletal muscle.","year":2010,"doi":"10.1152/ajpendo.00609.2009","url":"https://doi.org/10.1152/ajpendo.00609.2009","population":"not extracted","intervention_or_exposure":"not extracted","comparator":"not extracted","endpoint":"not extracted","effect":"not extracted","risk_of_bias":"not appraised in public sidecar","directness":"primary"}],"edges":[{"from":"b09d87ba-d35f-4c9b-aeba-4d2cca7e8d21","to":"claim_1","type":"contains_claim"},{"from":"b09d87ba-d35f-4c9b-aeba-4d2cca7e8d21","to":"claim_2","type":"contains_claim"},{"from":"b09d87ba-d35f-4c9b-aeba-4d2cca7e8d21","to":"claim_3","type":"contains_claim"}],"screening":{"identified":2,"screened":2,"excluded":0,"included":2,"included_or_retained":2,"flow":["identified","screened","excluded_with_reasons","included"],"wording":"2 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."]}}