scholarly journals Effects of Cooling During Exercise on Thermoregulatory Responses of Men With Paraplegia

2016 ◽  
Vol 96 (5) ◽  
pp. 650-658 ◽  
Author(s):  
Coen C.W.G. Bongers ◽  
Thijs M.H. Eijsvogels ◽  
Ilse J.W. van Nes ◽  
Maria T.E. Hopman ◽  
Dick H.J. Thijssen

Background People with spinal cord injury (SCI) have an altered afferent input to the thermoregulatory center, resulting in a reduced efferent response (vasomotor control and sweating capacity) below the level of the lesion. Consequently, core body temperature rises more rapidly during exercise in individuals with SCI compared with people who are able-bodied. Cooling strategies may reduce the thermophysiological strain in SCI. Objective The aim of this study was to examine the effects of a cooling vest on the core body temperature response of people with a thoracic SCI during submaximal exercise. Methods Ten men (mean age=44 years, SD=11) with a thoracic lesion (T4–T5 or below) participated in this randomized crossover study. Participants performed two 45-minute exercise bouts at 50% maximal workload (ambient temperature 25°C), with participants randomized to a group wearing a cooling vest or a group wearing no vest (separate days). Core body temperature and skin temperature were continuously measured, and thermal sensation was assessed every 3 minutes. Results Exercise resulted in an increased core body temperature, skin temperature, and thermal sensation, whereas cooling did not affect core body temperature. The cooling vest effectively decreased skin temperature, increased the core-to-trunk skin temperature gradient, and tended to lower thermal sensation compared with the control condition. Limitations The lack of differences in core body temperature among conditions may be a result of the relative moderate ambient temperature in which the exercise was performed. Conclusions Despite effectively lowering skin temperature and increasing the core-to-trunk skin temperature gradient, there was no impact of the cooling vest on the exercise-induced increase in core body temperature in men with low thoracic SCI.

2013 ◽  
Vol 58 (6) ◽  
pp. 1077-1085 ◽  
Author(s):  
Samuel Penna Wanner ◽  
Kátia Anunciação Costa ◽  
Anne Danieli Nascimento Soares ◽  
Valbert Nascimento Cardoso ◽  
Cândido Celso Coimbra

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Kazuyuki Miyamoto ◽  
Keisuke Suzuki ◽  
Hirokazu Ohtaki ◽  
Motoyasu Nakamura ◽  
Hiroki Yamaga ◽  
...  

Abstract Background Heatstroke is associated with exposure to high ambient temperature (AT) and relative humidity (RH), and an increased risk of organ damage or death. Previously proposed animal models of heatstroke disregard the impact of RH. Therefore, we aimed to establish and validate an animal model of heatstroke considering RH. To validate our model, we also examined the effect of hydration and investigated gene expression of cotransporter proteins in the intestinal membranes after heat exposure. Methods Mildly dehydrated adult male C57/BL6J mice were subjected to three AT conditions (37 °C, 41 °C, or 43 °C) at RH > 99% and monitored with WetBulb globe temperature (WBGT) for 1 h. The survival rate, body weight, core body temperature, blood parameters, and histologically confirmed tissue damage were evaluated to establish a mouse heatstroke model. Then, the mice received no treatment, water, or oral rehydration solution (ORS) before and after heat exposure; subsequent organ damage was compared using our model. Thereafter, we investigated cotransporter protein gene expressions in the intestinal membranes of mice that received no treatment, water, or ORS. Results The survival rates of mice exposed to ATs of 37 °C, 41 °C, and 43 °C were 100%, 83.3%, and 0%, respectively. From this result, we excluded AT43. Mice in the AT 41 °C group appeared to be more dehydrated than those in the AT 37 °C group. WBGT in the AT 41 °C group was > 44 °C; core body temperature in this group reached 41.3 ± 0.08 °C during heat exposure and decreased to 34.0 ± 0.18 °C, returning to baseline after 8 h which showed a biphasic thermal dysregulation response. The AT 41 °C group presented with greater hepatic, renal, and musculoskeletal damage than did the other groups. The impact of ORS on recovery was greater than that of water or no treatment. The administration of ORS with heat exposure increased cotransporter gene expression in the intestines and reduced heatstroke-related damage. Conclusions We developed a novel mouse heatstroke model that considered AT and RH. We found that ORS administration improved inadequate circulation and reduced tissue injury by increasing cotransporter gene expression in the intestines.


2008 ◽  
Vol 109 (2) ◽  
pp. 318-338 ◽  
Author(s):  
Daniel I. Sessler ◽  
David S. Warner ◽  
Mark A. Warner

Most clinically available thermometers accurately report the temperature of whatever tissue is being measured. The difficulty is that no reliably core-temperature-measuring sites are completely noninvasive and easy to use-especially in patients not undergoing general anesthesia. Nonetheless, temperature can be reliably measured in most patients. Body temperature should be measured in patients undergoing general anesthesia exceeding 30 min in duration and in patients undergoing major operations during neuraxial anesthesia. Core body temperature is normally tightly regulated. All general anesthetics produce a profound dose-dependent reduction in the core temperature, triggering cold defenses, including arteriovenous shunt vasoconstriction and shivering. Anesthetic-induced impairment of normal thermoregulatory control, with the resulting core-to-peripheral redistribution of body heat, is the primary cause of hypothermia in most patients. Neuraxial anesthesia also impairs thermoregulatory control, although to a lesser extent than does general anesthesia. Prolonged epidural analgesia is associated with hyperthermia whose cause remains unknown.


1984 ◽  
Vol 57 (6) ◽  
pp. 1738-1741 ◽  
Author(s):  
T. G. Waldrop ◽  
D. E. Millhorn ◽  
F. L. Eldridge ◽  
L. E. Klingler

Respiratory responses to increased skin temperatures were recorded in anesthetized cerebrate and in unanesthetized decerebrate cats. All were vagotomized, glomectomized, and paralyzed. Core body temperature and end-tidal Pco2 were kept constant with servoncontrollers. Stimulation of cutaneous nociceptors by heating the skin to 46 degrees C caused respiration to increase in both cerebrate and decerebrate cats. An even larger facilitation of respiration occurred when the skin temperature was elevated to 51 degrees C. However, respiration did not increase in either group of cats when the skin was heated to 41 degrees C to activate cutaneous warm receptors. The phenomenon of sensitization of nociceptors was observed. Spinal transection prevented all the respiratory responses to cutaneous heating. We conclude that noxious, but not nonnoxious, increases in skin temperature cause increases in respiratory output.


2019 ◽  
Vol 163 ◽  
pp. 104849 ◽  
Author(s):  
Wataru Iwasaki ◽  
Shuichi Ishida ◽  
Daisuke Kondo ◽  
Yuichi Ito ◽  
Jun Tateno ◽  
...  

2017 ◽  
Vol 12 (5) ◽  
pp. 662-667 ◽  
Author(s):  
Matthijs T.W. Veltmeijer ◽  
Dineke Veeneman ◽  
Coen C.C.W. Bongers ◽  
Mihai G. Netea ◽  
Jos W. van der Meer ◽  
...  

Purpose:Exercise increases core body temperature (TC) due to metabolic heat production. However, the exercise-induced release of inflammatory cytokines including interleukin-6 (IL-6) may also contribute to the rise in TC by increasing the hypothalamic temperature set point. This study investigated whether the exercise-induced increase in TC is partly caused by an altered hypothalamic temperature set point.Methods:Fifteen healthy, active men age 36 ± 14 y were recruited. Subjects performed submaximal treadmill exercise in 3 randomized test conditions: (1) 400 mg ibuprofen and 1000 mg acetaminophen (IBU/APAP), (2) 1000 mg acetaminophen (APAP), and (3) a control condition (CTRL). Acetaminophen and ibuprofen were used to block the effect of IL-6 at a central and peripheral level, respectively. TC, skin temperature, and heart rate were measured continuously during the submaximal exercise tests.Results:Baseline values of TC, skin temperature, and heart rate did not differ across conditions. Serum IL-6 concentrations increased in all 3 conditions. A significantly lower peak TC was observed in IBU/APAP (38.8°C ± 0.4°C) vs CTRL (39.2°C ± 0.5°C, P = .02) but not in APAP (38.9°C ± 0.4°C) vs CTRL. Similarly, a lower ΔTC was observed in IBU/APAP (1.7°C ± 0.3°C) vs CTRL (2.0°C ± 0.5°C, P < .02) but not in APAP (1.7°C ± 0.5°C) vs CTRL. No differences were observed in skin temperature and heart-rate responses across conditions.Conclusions:The combined administration of acetaminophen and ibuprofen resulted in an attenuated increase in TC during exercise compared with a CTRL. This observation suggests that a prostaglandin-E2-induced elevated hypothalamic temperature set point may contribute to the exercise-induced rise in TC.


Nutrients ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2797 ◽  
Author(s):  
Hitomi Ogata ◽  
Masaki Horie ◽  
Momoko Kayaba ◽  
Yoshiaki Tanaka ◽  
Akira Ando ◽  
...  

Breakfast is often described as “the most important meal of the day” and human studies have revealed that post-prandial responses are dependent on meal timing, but little is known of the effects of meal timing per se on human circadian rhythms. We evaluated the effects of skipping breakfast for 6 days on core body temperature, dim light melatonin onset, heart rate variability, and clock gene expression in 10 healthy young men, with a repeated-measures design. Subjects were provided an isocaloric diet three times daily (3M) or two times daily (2M, i.e., breakfast skipping condition) over 6 days. Compared with the 3M condition, the diurnal rhythm of the core body temperature in the 2M condition was delayed by 42.0 ± 16.2 min (p = 0.038). On the other hand, dim light melatonin onset, heart rate variability, and clock gene expression were not affected in the 2M condition. Skipping breakfast for 6 days caused a phase delay in the core body temperature in healthy young men, even though the sleep–wake cycle remained unchanged. Chronic effects of skipping breakfast on circadian rhythms remain to be studied.


2019 ◽  
Vol 127 (1) ◽  
pp. 168-177 ◽  
Author(s):  
Sayaka Aritake-Okada ◽  
Kosuke Tanabe ◽  
Yoshiko Mochizuki ◽  
Ryuji Ochiai ◽  
Masanobu Hibi ◽  
...  

The effects of exercise on sleep have been explored from various perspectives, but little is known about how the effects of acute exercise on sleep are produced through physiological functions. We used a protocol of multiple daytime sessions of moderate-intensity aerobic exercise and examined the subsequent effects on sleep structure, core body temperature (CBT), distal-proximal skin temperature gradient (DPG), and subjective parameters. Fourteen healthy men who did not exercise regularly were evaluated under the baseline (no exercise) and exercise conditions on a within-subject crossover basis. Under the exercise condition, each participant performed a 40-min aerobic workout at 40% of maximal oxygen intake, four times between morning and early evening. We observed a 33% increase in slow-wave sleep (SWS; P = 0.005), as well as increases in slow-wave activity (SWA; P = 0.026), the fast-sigma power/SWA ratio ( P = 0.005), and subjective sleep depth and restorativeness the following morning. Moreover, both CBT and the DPG increased during sleep after exercise ( P = 0.021 and P = 0.047, respectively). Regression analysis identified an increased nocturnal DPG during sleep after exercise as a factor in the increase in SWA. The fast-sigma/SWA ratio correlated with CBT. The performance of acute exercise promotes SWS with nocturnal elevation in the DPG. Both CBT and fast-sigma power may play a role in the specific physiological status of the body after exercise.NEW & NOTEWORTHY We used multiple daytime sessions of moderate-intensity aerobic exercise to examine the effects on the sleep structure, core body temperature (CBT), distal-proximal skin temperature gradient (DPG), and subjective parameters. Significant increases in slow-wave activity (SWA), CBT, DPG, fast-sigma power, and subjective parameters were observed during the night and the following morning. Nocturnal DPG is a factor in the increased SWA.


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