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Updated: May 13, 2026

In vitro Assessment of Myocardial Protection following Hypothermia-Preconditioning in a Human Cardiac Myocytes Model
Published on: October 27, 2020
Cold exposure attenuates post exercise cardiovagal reactivation and sympathetic withdrawal
Marcos A Sanchez-Gonzalez1, Arturo Figueroa
1Department of Biomedical Sciences, College of Medicine, The Florida State University, Tallahassee, FL, USA. mas08u@my.fsu.edu
Abstract:
In a crossover design we investigated cardiac autonomic responses (heart rate variability, HRV) to isometric handgrip exercise (IHG) in cold (4°C) and temperate (24°C, temp) conditions in 20 men that assumed the supine position for 30 min in an environmental chamber. After a 5 min rest, subjects performed 3 min of IHG followed by a 3 min recovery period (REC). During REC, the low frequency of HRV was lower while the high frequency and the square root of the mean squared differences of successive NN intervals were higher (P<0.05) than the rest in the temp compared to a full recovery in the cold. In conclusion, recovery from concurrent cold exposure and exercise impairs cardiovagal modulation which may precipitate cardiac events.
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