{"id":"9f9845ef-0468-5fe7-ae05-4ef27580718b","stable_key":"a8bedee0-a740-5bbb-921e-bfd144c7b68c:astaxanthin-cycling-positive-2011","predicate":"improves","statement":"After 4 mg/day for 28 days, the astaxanthin group improved its 20-km cycling time trial more than placebo in the 14 completers of a 21-person randomized study.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"bb14679c-114f-598a-91f6-21a1022bf51a","mechanism_event_label":"A small cycling study reported faster performance.","subject":{"id":"1bf8b9c0-9c38-5c8a-b5da-f00b0eeca36f","slug":"astaxanthin","display_name":"Astaxanthin","entity_type_key":"small_molecule"},"object":{"id":"6f077258-3a53-5fc0-9bd0-3d91179f08cb","slug":"human-astaxanthin-cycling-performance","display_name":"Human cycling time-trial performance after astaxanthin","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"bb14679c-114f-598a-91f6-21a1022bf51a","stable_key":"a8bedee0-a740-5bbb-921e-bfd144c7b68c:astaxanthin-cycling-positive-2011-event","event_type":"observed_relationship","label":"A small cycling study reported faster performance.","description":"After 4 mg/day for 28 days, the astaxanthin group improved its 20-km cycling time trial more than placebo in the 14 completers of a 21-person randomized study.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"1bf8b9c0-9c38-5c8a-b5da-f00b0eeca36f","slug":"astaxanthin","display_name":"Astaxanthin","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"6f077258-3a53-5fc0-9bd0-3d91179f08cb","slug":"human-astaxanthin-cycling-performance","display_name":"Human cycling time-trial performance after astaxanthin","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Seven completers per arm; time trial after two hours of exercise.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Attrition and small groups limit precision; substrate oxidation did not improve.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Astaxanthin collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"astaxanthin","display_name":"Astaxanthin","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"A small cycling study reported faster performance.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Effect of astaxanthin on cycling time trial performance. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21984399/ · DOI 10.1055/s-0031-1280779","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"26af48a3-6a08-577a-8eb0-e0a934e4d593","evidence_kind":"source_excerpt","locator":"Lines 454-460","start_line":454,"end_line":460,"excerpt":"## astaxanthin-cycling-positive-2011\nA small cycling study reported faster performance.\nAfter 4 mg/day for 28 days, the astaxanthin group improved its 20-km cycling time trial more than placebo in the 14 completers of a 21-person randomized study.\nModel: Seven completers per arm; time trial after two hours of exercise.\nLimitations: Attrition and small groups limit precision; substrate oxidation did not improve.\nEvidence access: Primary abstract\nEffect of astaxanthin on cycling time trial performance. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21984399/ · DOI 10.1055/s-0031-1280779","model_system":"Seven completers per arm; time trial after two hours of exercise.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"4fd91ea6-78b4-5bfe-93e3-686fbef9f678","stable_key":"import-a8bedee0-a740-5bbb-921e-bfd144c7b68c","title":"Astaxanthin: transport, membrane chemistry, signaling and nutrient interactions (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"98640e32f62e6c0387578165342ad21b3d2325701fcfdbb5c48886c783040e5e","revision_id":"a82757ce-1feb-582c-a5fc-f7de36308f1f","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[{"id":"6061c385-019a-5def-825f-819530a7e289","title":"Does astaxanthin improve cycling time-trial performance?","kind":"contradiction","status":"open","why":"Small 2011 and 2021 randomized studies reported improved time trials, while the 2013 trained-cyclist trial found no benefit despite increased plasma astaxanthin. These differing efficacy results are a research uncertainty, not correction of an earlier draft.","resolution":"Unresolved across trials. Preserve training status, dose, duration, formulation, attrition and exercise protocol as candidate effect modifiers. The studies do not estimate identical interventions; a null trial is not proof of zero benefit in every setting, and positive small trials do not establish a universal effect. Discuss proposed mechanisms without treating them as an established reconciliation.","created_at":"2026-09-19 05:29:59","record_type":"conflict","display_label":"Recorded conflict","record_url":"/conflicts/6061c385-019a-5def-825f-819530a7e289","sides":[{"conflict_id":"6061c385-019a-5def-825f-819530a7e289","ordinal":0,"label":"2011 small positive trial","revision_id":"a82757ce-1feb-582c-a5fc-f7de36308f1f","start_line":454,"end_line":460,"quote":"## astaxanthin-cycling-positive-2011\nA small cycling study reported faster performance.\nAfter 4 mg/day for 28 days, the astaxanthin group improved its 20-km cycling time trial more than placebo in the 14 completers of a 21-person randomized study.\nModel: Seven completers per arm; time trial after two hours of exercise.\nLimitations: Attrition and small groups limit precision; substrate oxidation did not improve.\nEvidence access: Primary abstract\nEffect of astaxanthin on cycling time trial performance. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21984399/ · DOI 10.1055/s-0031-1280779","source_key":"import-a8bedee0-a740-5bbb-921e-bfd144c7b68c","source_title":"Astaxanthin: transport, membrane chemistry, signaling and nutrient interactions (2026-09-19)","claim_ids":["9f9845ef-0468-5fe7-ae05-4ef27580718b"]},{"conflict_id":"6061c385-019a-5def-825f-819530a7e289","ordinal":1,"label":"2013 trained-cyclist null result","revision_id":"a82757ce-1feb-582c-a5fc-f7de36308f1f","start_line":462,"end_line":468,"quote":"## astaxanthin-cycling-null-2013\nHigher blood exposure did not translate into better performance.\nIn 32 well-trained male cyclists, 20 mg/day for four weeks raised plasma astaxanthin but did not improve time-trial performance or fat oxidation.\nModel: Human randomized trial in trained cyclists.\nLimitations: Different dose, training status and protocol from the positive trials; these are candidate explanations, not a demonstrated reconciliation.\nEvidence access: Primary abstract\nAstaxanthin supplementation does not augment fat use or improve endurance performance. · 2013 · https://pubmed.ncbi.nlm.nih.gov/23274592/ · DOI 10.1249/MSS.0b013e31827fddc4","source_key":"import-a8bedee0-a740-5bbb-921e-bfd144c7b68c","source_title":"Astaxanthin: transport, membrane chemistry, signaling and nutrient interactions (2026-09-19)","claim_ids":["389e453d-bb6f-5475-8be8-a38ae6153a4c"]},{"conflict_id":"6061c385-019a-5def-825f-819530a7e289","ordinal":2,"label":"2021 small crossover positive trial","revision_id":"a82757ce-1feb-582c-a5fc-f7de36308f1f","start_line":470,"end_line":476,"quote":"## astaxanthin-cycling-positive-2021\nAnother small trial found a modest performance improvement.\nTwelve recreationally trained men completed a crossover trial of 12 mg/day for seven days; 40-km performance improved by about 1.2%, or 51 seconds on average.\nModel: Human crossover trial with 14-day washout.\nLimitations: Small sample; a reported fat-oxidation difference occurred at the final 39–40 km and should not be generalized to the entire event.\nEvidence access: Primary abstract\nThe effect of astaxanthin supplementation on performance and fat oxidation during a 40 km cycling time trial. · 2021 · https://pubmed.ncbi.nlm.nih.gov/32660833/ · DOI 10.1016/j.jsams.2020.06.017","source_key":"import-a8bedee0-a740-5bbb-921e-bfd144c7b68c","source_title":"Astaxanthin: transport, membrane chemistry, signaling and nutrient interactions (2026-09-19)","claim_ids":["c95d96a3-15be-556b-8d07-75e8db7dcbbd"]}]}],"corrections":[],"research":null}