TY - JOUR
T1 - The "ice-mile"
T2 - Case study of 2 swimmers' selected physiological responses and performance
AU - Kenny, John
AU - Cullen, Sarahjane
AU - Warrington, Giles D.
N1 - Publisher Copyright:
© 2017 Human Kinetics, Inc.
PY - 2017/5
Y1 - 2017/5
N2 - Purpose: "Ice-mile" swimming presents significant physiological challenges and potential safety issues, but few data are available. This study examined deep body temperature (BT), respiratory rate (RR), and swim performance in 2 swimmers completing an ice-mile swim of 1 mile (1600 m) in water less than 5°C. Methods: Two male cold-water-habituated swimmers completed a 1-mile lake swim in 3.9°C water. For comparative purposes, they completed an indoor 1-mile swim in 28.1°C water. The Equivital physiological monitoring system was used to record BT and RR before, during, and after each swim. Total time to complete the swims and 400-m splits were recorded. Results: One swimmer became hypothermic after 27 min while swimming, reaching BT of 33.7°C at swim's end. On exiting the water the swimmers experienced large BT after-drops of -3.6°C and -2.4°C, reaching low points of 33.2°C and 31.3°C 38 and 23 min postswim, respectively. Respiratory rate and swim pace decreased over the course of the ice-mile swim for both swimmers. Swim pace for 1 swimmer declined sharply in the final 400-m lap of the ice mile when he was hypothermic. Both swimmers remained hypothermic 60 min postswim (34.2°C and 33.4°C). Conclusions: Ice-mile swimmers may become hypothermic while swimming, and the postswim BT after drop may expose them to dangerous levels of hypothermia. Pace and RR should be monitored as proxies for a swimmer's physiological state. Postswim recovery should also be monitored for hypothermia for at least 1 h.
AB - Purpose: "Ice-mile" swimming presents significant physiological challenges and potential safety issues, but few data are available. This study examined deep body temperature (BT), respiratory rate (RR), and swim performance in 2 swimmers completing an ice-mile swim of 1 mile (1600 m) in water less than 5°C. Methods: Two male cold-water-habituated swimmers completed a 1-mile lake swim in 3.9°C water. For comparative purposes, they completed an indoor 1-mile swim in 28.1°C water. The Equivital physiological monitoring system was used to record BT and RR before, during, and after each swim. Total time to complete the swims and 400-m splits were recorded. Results: One swimmer became hypothermic after 27 min while swimming, reaching BT of 33.7°C at swim's end. On exiting the water the swimmers experienced large BT after-drops of -3.6°C and -2.4°C, reaching low points of 33.2°C and 31.3°C 38 and 23 min postswim, respectively. Respiratory rate and swim pace decreased over the course of the ice-mile swim for both swimmers. Swim pace for 1 swimmer declined sharply in the final 400-m lap of the ice mile when he was hypothermic. Both swimmers remained hypothermic 60 min postswim (34.2°C and 33.4°C). Conclusions: Ice-mile swimmers may become hypothermic while swimming, and the postswim BT after drop may expose them to dangerous levels of hypothermia. Pace and RR should be monitored as proxies for a swimmer's physiological state. Postswim recovery should also be monitored for hypothermia for at least 1 h.
KW - After-drop
KW - Deep body temperature
KW - Hypothermia
KW - Respiratory rate
KW - Swim performance
UR - http://www.scopus.com/inward/record.url?scp=85024380110&partnerID=8YFLogxK
U2 - 10.1123/ijspp.2016-0323
DO - 10.1123/ijspp.2016-0323
M3 - Article
C2 - 27736258
AN - SCOPUS:85024380110
SN - 1555-0265
VL - 12
SP - 711
EP - 714
JO - International Journal of Sports Physiology and Performance
JF - International Journal of Sports Physiology and Performance
IS - 5
ER -