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Sleep quality is self-reported.\nexposure: 5 minutes of seated recovery at 15 degrees C after the last training session each day\nevidence_span: {\"source_cache\": \"artifacts/cold-research/21941017.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"0cd5dfad3441e660d67198cf010e5fa160936cb66c37b129b575d29d74940910\", \"start_char\": 0, \"end_char\": 1567, \"text_sha256\": \"0cd5dfad3441e660d67198cf010e5fa160936cb66c37b129b575d29d74940910\"}\n[cold-p21941017] Effect of daily cold water immersion on heart rate variability and subjective ratings of well-being in highly trained swimmers. (2012). https://pubmed.ncbi.nlm.nih.gov/21941017/ DOI: 10.1123/ijspp.7.1.33","model_system":"Eight highly trained swimmers over two matched training weeks in randomised order","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [cold-p21941017] Effect of daily cold water immersion on heart rate variability and subjective ratings of well-being in highly trained swimmers. (2012). https://pubmed.ncbi.nlm.nih.gov/21941017/ DOI: 10.1123/ijspp.7.1.33","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"feeccadc-1392-573e-a0b5-0939ee5de6e2","stable_key":"import-b3c3f45a-50fb-5b79-98d7-5e5228df00db","title":"Cold water immersion: cold sensing, heat production, the catecholamine axis and what repeated exposure changes (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"557f074d372c49c502c34e648651aff7ebf2c8816305d2d2f08e338a7e96a5f0","revision_id":"ecc19e8d-40db-5b5d-b98e-0507f645976c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}