Thermal, Cardiac and
Adrenergic Responses to Repeated Local Cooling
L. JANSKÝ1, E. MATOUŠKOVÁ1,
V. VÁVRA1, S. VYBÍRAL2, P. JANSKÝ3,
D. JANDOVÁ4, I. KNÍŽKOVÁ5, P. KUNC5
1Faculty of Biology, South Bohemian University, České
Budějovice, 2Faculty of Science, and 3Second
Faculty of Medicine, Charles University, Prague, 4Priessnitz
Spa, Jeseník, 5Research Institute of Animal
Production, Uhříněves, Czech Republic
Received date July 4, 2005
Accepted date November 2, 2005
On-line available December 12, 2005
Summary
The aim of this study was to ascertain whether repeated local
cooling induces the same or different adaptational responses as
repeated whole body cooling. Repeated cooling of the legs
(immersion into 12 °C water up to the knees for 30 min, 20 times
during 4 weeks = local cold adaptation – LCA) attenuated the
initial increase in heart rate and blood pressure currently
observed in control subjects immersed in cold water up to the
knees. After LCA the initial skin temperature decrease tended to
be lower, indicating reduced vasoconstriction. Heart rate and
systolic blood pressure appeared to be generally lower during
rest and during the time course of cooling in LCA humans, when
compared to controls. All these changes seem to indicate
attenuation of the sympathetic tone. In contrast, the sustained
skin temperature in different areas of the body (finger, palm,
forearm, thigh, chest) appeared to be generally lower in LCA
subjects than in controls (except for temperatures on the
forehead). Plasma levels of catecholamines (measured 20 and 40
min after the onset of cooling) were also not influenced by
local cold adaptation. Locally cold adapted subjects, when
exposed to whole body cold water immersion test, showed no
change in the threshold temperature for induction of cold
thermogenesis. This indicates that the hypothermic type of cold
adaptation, typically occurring after systemic cold adaptation,
does not appear after local cold adaptation of the intensity
used. It is concluded that in humans the cold adaptation due to
repeated local cooling of legs induces different physiological
changes than systemic cold adaptation.
Key words
Local cold adaptation • Cardiovascular and metabolic responses •
Man
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