Influence of postexercise cooling techniques on heart rate variability in men
Leicht, Anthony S., Sinclair, Wade H., Patterson, Mark J., Rudzki, Stephan, Tulppo, Mikko P., Fogarty, Alison L., and Winter, Sue (2009) Influence of postexercise cooling techniques on heart rate variability in men. Experimental Physiology, 94 (6). pp. 695-703.
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The reduction of core body temperature (TC) is vitally important in the treatment of hyperthermia; however, little is known regarding the impact of cooling treatments on the autonomic control of heart rate (HR). The aim of the present study was to examine the influence of three field-based hyperthermia treatments on the neural control of HR via heart rate variability (HRV). Following exercise-induced hyperthermia (TC ∼40.0°C) in a warm environment (34.2 ± 0.5°C), nine healthy, active men were treated during recovery, in a randomized order, with intravenous cold saline infusion (IV) or ice packs (ICE) or fan cooling with intermittent water spray (FAN) for 40 min. During each treatment, HR dynamics via power spectral (VLF, LF, HF), Poincare plot (SD1, SD2), approximate entropy (ApEn) and short- (α1) and long-term (α2) fractal scaling analyses were determined every 10 min. At recovery onset, HR and TC were similar between treatments and were significantly reduced over the 40 min recovery period. During recovery, HR and α2 were significantly reduced from initial levels but were significantly greater for IV compared with ICE and FAN. In contrast, VLF, LF, HF, SD1, SD2 and ApEn increased during recovery, with all being significantly lower for IV compared with ICE and/or FAN. The present results demonstrated that IV, compared with ICE and FAN, resulted in significantly greater HR, reduced spectral and geometrical HRV, lower HR complexity and reduced long-term HR control, indicative of reduced vagal and/or increased sympathetic modulation. Specific treatments for exercise-induced hyperthermia may result in an altered sympathovagal balance that requires further examination.
|Item Type:||Article (Refereed Research - C1)|
|Keywords:||hyperthermia, recovery, autonomic control, vagal, non-linear|
|Date Deposited:||26 Aug 2009 04:53|
|FoR Codes:||11 MEDICAL AND HEALTH SCIENCES > 1109 Neurosciences > 110901 Autonomic Nervous System @ 30%
11 MEDICAL AND HEALTH SCIENCES > 1106 Human Movement and Sports Science > 110602 Exercise Physiology @ 70%
|SEO Codes:||92 HEALTH > 9204 Public Health (excl. Specific Population Health) > 920405 Environmental Health @ 50%
92 HEALTH > 9204 Public Health (excl. Specific Population Health) > 920408 Health Status (e.g. Indicators of Well-Being) @ 50%
|Citation Count from Web of Science||