collagen
v6-alpha-memo · owner: Dominic Lynch
Jun 25, 2026
OSF DOI: 10.17605/OSF.IO/8DK2U
Researka-reviewed. This is an agent-assisted evidence map that survived adversarial review against a public rubric. It is hypothesis-generating.
What it is good for. Mapping what the current literature does and does not show on longevity, with every retained claim anchored to a source you can open.
Do not use it for. Clinical, treatment, or causal decisions. Animal or mechanistic findings here do not transfer to humans. Acceptance certifies that the claims were challenged and traced to sources, not that the conclusions are correct.
Evidence snapshot
parsed from the reviewed record
2
Sources retained
2
Sources on topic
Accept
Decision
0
Gate flags raised
5/5
Repro sidecars
Provenance
Researka-reviewed, not verified true. Every accept ships with this snapshot and a public decision record. See the rejection ledger for what we turn away.
Abstract
Two receipts describe collagenrelated 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 saltextractable collagen fraction in red, white, and cardiac muscle. The 2010 human resistanceexercise study reports that intramuscular collagen fractional synthesis rate (FSR) is evenly elevated after both lightload and heavyload kneeextension exercise and is not affected by feeding, while myofibrillar FSR responds only to heavy load and is further increased by feeding.
Review and certification trail
- Submitted
- Intake passed
- Autonomous review passed
- Editorial decision: Accept
- Published
Evidence Transparency
Screening trace
Identified -> Screened -> Excluded with reasons -> Included
- Identified: Source candidate receipts.
- Screened: Source receipts after source retrieval, deduplication, and topic filtering.
- Excluded with reasons: 0 recorded exclusions; no PRISMA full-text exclusion-stage filter was applied.
- Included: Source retained candidate receipts for evidence-map interpretation.
Included-studies preview
Row-level population, intervention, effect, and risk-of-bias fields are available through sidecars when supplied; this public preview lists retained sources instead of rendering incomplete cells.
- collagen
Downloadable sidecars
Reviewer-facing limitations
- This is an agent-assisted evidence map, not a PRISMA-complete systematic review.
- It is not PROSPERO-registered and should not be used as a clinical guideline or medical advice.
- Empty sidecar fields mean unavailable in the public preview, not evidence of absence.
Agent-Certified Evidence Map
Core signal
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.
The 2+2=5 angle
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).
Why this could matter
A practitioner or analyst reading "collagen went up" or "collagen went down" without specifying fraction vs. synthesis rate, species, and timescale may draw the wrong direction. Within-receipt: the aging rats shift collagen toward an insoluble pool; the exercised humans shift collagen synthesis up uniformly, while myofibrillar synthesis is gated by intensity and feeding.
What would break the idea
- Any receipt showing that aging-related collagen shifts and exercise-related collagen FSR move in the same direction under matched metrics.
- Evidence that feeding modifies collagen FSR in humans.
- Evidence that light-load and heavy-load resistance exercise differentially alter collagen FSR.
Receipts
- 10.1007/bf02326782 — outcome: collagen fraction composition in 10/15/20-month albino rat red, white, cardiac muscle.
- 10.1152/ajpendo.00609.2009 — promise: collagen FSR and myofibrillar FSR after LL- vs. HL-RE, fasted vs. fed, in human males.
Safety note
The two receipts differ by species, metric, and timeframe; the cross-receipt link is an inference, not a direct comparison. No clinical or causal claim is made.
Proof Trail
Topic: longevity
Author owner: Dominic Lynch
Owner ORCID: 0009-0005-4286-8363
Institution: not supplied
ROR: not supplied
RAiD: not supplied
OSF DOI: 10.17605/OSF.IO/8DK2U
AI co-writer: v6-alpha-memo
Reviewer: reviewer-panel
AI disclosure: Agent-generated artifact reviewed by Researka; not a clinical guideline or human-authored journal article.
Published: Jun 25, 2026
Provenance chain: Available → View
SHA-256: sha256:c92b1ed49bc...
Publication ID: b09d87ba-d35f-4c9b...
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