title: Diving bradycardia of elderly Korean women divers, haenyeo, in cold seawater: a field report.
abstract: The purpose of the present field study was to explore diving patterns and heart rate of elderly Korean women divers (haenyeo) while breath-hold diving in cold seawater. We hypothesized that the decreasing rate in heart rate of elderly haenyeos during breath-hold diving was greater and total diving time was shorter than those of young haenyeos from previous studies. Nine haenyeos participated in a field study [68 ± 10 yr in age, ranged from 56 to 83 yr] at a seawater temperature of 10 to 13 °C. Average total diving time including surface swimming time between dives was 253 ± 73 min (155-341 min). Total frequency of dives was 97 ± 28 times and they dived 23 ± 8 times per hour. All haenyeos showed diving bradycardia with a decreased rate of 20 ± 8% at the bottom time (101 ± 20 bpm) when compared to surface swimming time (125 ± 16 bpm) in the sea. Older haenyeos among the nine elderly haenyeos had shorter diving time, less diving frequencies, and lower heart rate at work (p<0.05). These reductions imply that haenyeos voluntarily adjust their workload along with advancing age and diminished cardiovascular functions.
authors.affiliation: College of Human Ecology, Seoul National University, Republic of Korea.
authors.forename: Joo-Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Hyo-Hyun
authors.initials: HH
authors.lastname: Lee
authors.forename: Siyeon
authors.initials: S
authors.lastname: Kim
authors.forename: Young-Joon
authors.initials: YJ
authors.lastname: Jang
authors.forename: Yoon-Jeong
authors.initials: YJ
authors.lastname: Baek
authors.forename: Kwon-Yong
authors.initials: KY
authors.lastname: Kang
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001919:Bradycardia / Q000209:etiology*; D062485:Breath Holding; D003080:Cold Temperature; D004242:Diving / Q000502:physiology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008875:Middle Aged; D016272:Occupational Health; D056910:Republic of Korea; D012623:Seawater; D013997:Time Factors; D016526:Workload