HEAT TRANSFER MODEL FOR PREDICTING SURVIVAL TIME IN COLD WATER IMMERSION

2005 ◽  
Vol 17 (04) ◽  
pp. 159-166 ◽  
Author(s):  
F. TARLOCHAN ◽  
S. RAMESH

In the present paper a heat transfer (HT) model to estimate survival time of individual stranded in cold water such as at sea is proposed. The HT model was derived based on the assumption that the body specific heat capacity and thermal conductance are not time dependent. The solution to the HT model simulates expected survival time as a function of water temperature, metabolism rate, skin, muscle and fat thickness, insulation thermal conductivity and thickness, height and weight of the subject. Although, these predictions must be considered approximate due to the complex nature of the variables involved, the proposed HT model can be employed to determine supplemental body insulation such as personal protective clothing to meet a predefined survival time in any given water temperature. In particular, the results obtained are useful as a decision aid in search and rescue mission in predicting survival time for shipwreck victims at sea.

2003 ◽  
Vol 95 (1) ◽  
pp. 89-96 ◽  
Author(s):  
Peter Tikuisis

Certain previous studies suggest, as hypothesized herein, that heat balance (i.e., when heat loss is matched by heat production) is attained before stabilization of body temperatures during cold exposure. This phenomenon is explained through a theoretical analysis of heat distribution in the body applied to an experiment involving cold water immersion. Six healthy and fit men (mean ± SD of age = 37.5 ± 6.5 yr, height = 1.79 ± 0.07 m, mass = 81.8 ± 9.5 kg, body fat = 17.3 ± 4.2%, maximal O2 uptake = 46.9 ± 5.5 l/min) were immersed in water ranging from 16.4 to 24.1°C for up to 10 h. Core temperature (Tco) underwent an insignificant transient rise during the first hour of immersion, then declined steadily for several hours, although no subject's Tco reached 35°C. Despite the continued decrease in Tco, shivering had reached a steady state of ∼2 × resting metabolism. Heat debt peaked at 932 ± 334 kJ after 2 h of immersion, indicating the attainment of heat balance, but unexpectedly proceeded to decline at ∼48 kJ/h, indicating a recovery of mean body temperature. These observations were rationalized by introducing a third compartment of the body, comprising fat, connective tissue, muscle, and bone, between the core (viscera and vessels) and skin. Temperature change in this “mid region” can account for the incongruity between the body's heat debt and the changes in only the core and skin temperatures. The mid region temperature decreased by 3.7 ± 1.1°C at maximal heat debt and increased slowly thereafter. The reversal in heat debt might help explain why shivering drive failed to respond to a continued decrease in Tco, as shivering drive might be modulated by changes in body heat content.


2015 ◽  
Vol 50 (8) ◽  
pp. 792-799 ◽  
Author(s):  
Kevin C. Miller ◽  
Erik E. Swartz ◽  
Blaine C. Long

Context Current treatment recommendations for American football players with exertional heatstroke are to remove clothing and equipment and immerse the body in cold water. It is unknown if wearing a full American football uniform during cold-water immersion (CWI) impairs rectal temperature (Trec) cooling or exacerbates hypothermic afterdrop. Objective To determine the time to cool Trec from 39.5°C to 38.0°C while participants wore a full American football uniform or control uniform during CWI and to determine the uniform's effect on Trec recovery postimmersion. Design Crossover study. Setting Laboratory. Patients or Other Participants A total of 18 hydrated, physically active, unacclimated men (age = 22 ± 3 years, height = 178.8 ± 6.8 cm, mass = 82.3 ± 12.6 kg, body fat = 13% ± 4%, body surface area = 2.0 ± 0.2 m2). Intervention(s) Participants wore the control uniform (undergarments, shorts, crew socks, tennis shoes) or full uniform (control plus T-shirt; tennis shoes; jersey; game pants; padding over knees, thighs, and tailbone; helmet; and shoulder pads). They exercised (temperature approximately 40°C, relative humidity approximately 35%) until Trec reached 39.5°C. They removed their T-shirts and shoes and were then immersed in water (approximately 10°C) while wearing each uniform configuration; time to cool Trec to 38.0°C (in minutes) was recorded. We measured Trec (°C) every 5 minutes for 30 minutes after immersion. Main Outcome Measure(s) Time to cool from 39.5°C to 38.0°C and Trec. Results The Trec cooled to 38.0°C in 6.19 ± 2.02 minutes in full uniform and 8.49 ± 4.78 minutes in control uniform (t17 = −2.1, P = .03; effect size = 0.48) corresponding to cooling rates of 0.28°C·min−1 ± 0.12°C·min−1 in full uniform and 0.23°C·min−1 ± 0.11°C·min−1 in control uniform (t17 = 1.6, P = .07, effect size = 0.44). The Trec postimmersion recovery did not differ between conditions over time (F1,17 = 0.6, P = .59). Conclusions We speculate that higher skin temperatures before CWI, less shivering, and greater conductive cooling explained the faster cooling in full uniform. Cooling rates were considered ideal when the full uniform was worn during CWI, and wearing the full uniform did not cause a greater postimmersion hypothermic afterdrop. Clinicians may immerse football athletes with hyperthermia wearing a full uniform without concern for negatively affecting body-core cooling.


2015 ◽  
Vol 46 (4) ◽  
pp. 503-514 ◽  
Author(s):  
Aryane Flauzino Machado ◽  
Paulo Henrique Ferreira ◽  
Jéssica Kirsch Micheletti ◽  
Aline Castilho de Almeida ◽  
Ítalo Ribeiro Lemes ◽  
...  

2016 ◽  
Vol 51 (6) ◽  
pp. 500-501 ◽  
Author(s):  
Emma A. Nye ◽  
Jessica R. Edler ◽  
Lindsey E. Eberman ◽  
Kenneth E. Games

Reference: Zhang Y, Davis JK, Casa DJ, Bishop PA. Optimizing cold water immersion for exercise-induced hyperthermia: a meta-analysis. Med Sci Sports Exerc. 2015;47(11):2464−2472. Clinical Questions: Do optimal procedures exist for implementing cold-water immersion (CWI) that yields high cooling rates for hyperthermic individuals? Data Sources: One reviewer performed a literature search using PubMed and Web of Science. Search phrases were cold water immersion, forearm immersion, ice bath, ice water immersion, immersion, AND cooling. Study Selection: Studies were included based on the following criteria: (1) English language, (2) full-length articles published in peer-reviewed journals, (3) healthy adults subjected to exercise-induced hyperthermia, and (4) reporting of core temperature as 1 outcome measure. A total of 19 studies were analyzed. Data Extraction: Pre-immersion core temperature, immersion water temperature, ambient temperature, immersion duration, and immersion level were coded a priori for extraction. Data originally reported in graphical form were digitally converted to numeric values. Mean differences comparing the cooling rates of CWI with passive recovery, standard deviation of change from baseline core temperature, and within-subjects r were extracted. Two independent reviewers used the Physiotherapy Evidence Database (PEDro) scale to assess the risk of bias. Main Results: Cold-water immersion increased the cooling rate by 0.03°C/min (95% confidence interval [CI] = 0.03, 0.04°C/min) compared with passive recovery. Cooling rates were more effective when the pre-immersion core temperature was ≥38.6°C (P = .023), immersion water temperature was ≤10°C (P = .036), ambient temperature was ≥20°C (P = .013), or immersion duration was ≤10 minutes (P < .001). Cooling rates for torso and limb immersion (mean difference = 0.04°C/min, 95% CI = 0.03, 0.06°C/min) were higher (P = .028) than those for forearm and hand immersion (mean difference = 0.01°C/min, 95% CI = −0.01, 0.04°C/min). Conclusions: Hyperthermic individuals were cooled twice as fast by CWI as by passive recovery. Therefore, the former method is the preferred choice when treating patients with exertional heat stroke. Water temperature should be <10°C, with the torso and limbs immersed. Insufficient published evidence supports CWI of the forearms and hands.


2021 ◽  
Vol 9 (2) ◽  
pp. 118
Author(s):  
Dewi Sartika

Introduction: DOMS is a complaint of muscle pain experienced by athletes by exercising overloadedly. DOMS pain tolerance improvement was carried out with several interventions, in the form of a combination of stretching with cold water immersion, and stretching with contrast water immersion. The purpose of this research is to proving which comparison of physiotherapy interventions is better for DOMS pain tolerance improvement. Method: The research was carried out in the Ngurah Rai athletics field in Denpasar in January 2020, experimental in nature with a pretest and post test two group design. Samples were male athletes divided into two groups, each group consisting of 9 respondens. Group I was given a combination of stretching and cold water immersion, Group II was given a combination of stretching and water immersion in contrast. Cold water temperature is 10 ?C and warm water temperature 36-40 ?C. Pain tolerance value measured by sphygmomanometer placed on the calf. The higher the value mmHg, the higher the tolerance would be. Result: Results in Group I, the mean pain tolerance before intervention was 153 ± 7.76 (mmHg) and the mean after intervention (48 hours) 206 ± 8.32 (mmHg) with p = 0,000 (p <0.05). In Group II, the mean pain tolerance before intervention was 154 ± 8.35 (mmHg) and after intervention (48 hours) 188.4 ± 6.95 (mmHg) with a value of p = 0,000 (p <0.05). This showed a significant increase in pain tolerance in each group. Statistical tests conducted between the two groups also showed significant differences, with a result of p = 0,000 (p <0.05) where the value of pain tolerance in Group I was better than Group II. Conclusions: combination of stretching and cold water immersion is better than the combination of stretching and water immersion in contrast in reducing DOMS.     Keywords: Delayed onset muscle soreness; stretching; cold water; contrast water immersion.


1992 ◽  
Vol 262 (4) ◽  
pp. R617-R623 ◽  
Author(s):  
K. B. Pandolf ◽  
R. W. Gange ◽  
W. A. Latzka ◽  
I. H. Blank ◽  
A. J. Young ◽  
...  

Thermoregulatory responses during cold-water immersion (water temperature 22 degrees C) were compared in 10 young men before as well as 24 h and 1 wk after twice the minimal erythemal dose of ultraviolet-B radiation that covered approximately 85% of the body surface area. After 10 min of seated rest in cold water, the mean exercised for 50 min on a cycle ergometer (approximately 51% of maximal aerobic power). Rectal temperature, regional and mean heat flow (hc), mean skin temperature from five sites, and hearrt rate were measured continuously for all volunteers while esophageal temperature was measured for six subjects. Venous blood samples were collected before and after cold water immersion. The mean skin temperature was higher (P less than 0.05) throughout the 60-min cold water exposure both 24 h and 1 wk after sunburn compared with before sunburn. Mean hc was higher (P less than 0.05) after 10 min resting immersion and during the first 10 min of exercise when 24 h postsunburn was compared with presunburn, with the difference attributed primarily to higher hc from the back and chest. While rectal temperature and heart rate did not differ between conditions, esophageal temperature before immersion and throughout the 60 min of cold water immersion was higher (P less than 0.05) when 24 h postsunburn was compared with presunburn. Plasma volume increased (P less than 0.05) after 1 wk postsunburn compared with presunburn, whereas plasma protein concentration was reduced (P less than 0.05). After exercise cortisol was greater (P less than 0.05) 24 h postsunburn compared with either presunburn or 1 wk postsunburn.(ABSTRACT TRUNCATED AT 250 WORDS)


Author(s):  
Anup K. Paul ◽  
Swarup A. Zachariah ◽  
Liang Zhu ◽  
Rupak K. Banerjee

Understanding the thermal response of the human body under various environmental and thermal stress conditions is of growing importance. Calculation of the core body temperature and the survivability of the body during immersion in cold water require detailed modeling of both the body tissue and the time-dependent blood temperature. Predicting body temperature changes under cold stress conditions is considered challenging since factors like thickness of the skin and blood perfusion within the skin layer become influential. Hence, the aim of this research was to demonstrate the capability of a recently developed whole body heat transfer model that simulates the tissue-blood interaction to predict the cooling of the body during immersion in cold water. It was shown that computed drop in core temperature agrees within 0.57 °C of the results calculated using a detailed network model. The predicted survival time in 0 °C water was less than an hour whereas in 18.5 °C water, the body attained a relatively stable core temperature of 34 °C in 2.5 hours.


2017 ◽  
Vol 12 (1) ◽  
pp. 2-9 ◽  
Author(s):  
Jessica M. Stephens ◽  
Shona Halson ◽  
Joanna Miller ◽  
Gary J. Slater ◽  
Christopher D. Askew

The use of cold-water immersion (CWI) for postexercise recovery has become increasingly prevalent in recent years, but there is a dearth of strong scientific evidence to support the optimization of protocols for performance benefits. While the increase in practice and popularity of CWI has led to multiple studies and reviews in the area of water immersion, the research has predominantly focused on performance outcomes associated with postexercise CWI. Studies to date have generally shown positive results with enhanced recovery of performance. However, there are a small number of studies that have shown CWI to have either no effect or a detrimental effect on the recovery of performance. The rationale for such contradictory responses has received little attention but may be related to nuances associated with individuals that may need to be accounted for in optimizing prescription of protocols. To recommend optimal protocols to enhance athletic recovery, research must provide a greater understanding of the physiology underpinning performance change and the factors that may contribute to the varied responses currently observed. This review focuses specifically on why some of the current literature may show variability and disparity in the effectiveness of CWI for recovery of athletic performance by examining the body temperature and cardiovascular responses underpinning CWI and how they are related to performance benefits. This review also examines how individual characteristics (such as physique traits), differences in water-immersion protocol (depth, duration, temperature), and exercise type (endurance vs maximal) interact with these mechanisms.


Author(s):  
Wélia Yasmin Horacio dos Santos ◽  
Felipe J. Aidar ◽  
Dihogo Gama de Matos ◽  
Roland Van den Tillaar ◽  
Anderson Carlos Marçal ◽  
...  

Background: Recovery from training is vital as it ensures training and performance to continue at high intensities and longer durations to stimulate the body and cause further adaptations. Objective: To evaluate different methods of post-workout recovery in Paralympic powerlifting athletes. Methods: Twelve male athletes participated (25.4 ± 3.3 years; 70.3 ± 12.1 kg). The presence of muscle edema, pain threshold, plasma cytokines, and performance measurement were evaluated five times. The recovery methods used in this study were passive recovery (PR), dry needling (DN), and cold-water immersion (CWI). Results: The data analysis showed that the maximal force decreased compared to the pretest value at 15 min and 2 h. The results also revealed that CWI and DN increased Interleukin 2 (IL-2) levels from 24 to 48 h more than that from 2 h to 24 h. After DN, muscle thickness did not increase significantly in any of the muscles, and after 2 h, muscle thickness decreased significantly again in the major pectoralis muscle. After CWI, pain pressure stabilized after 15 min and increased significantly again after 2 h for acromial pectoralis. Conclusion: The strength training sessions generate several changes in metabolism and different recovery methods contribute differently to maintain homeostasis in Paralympic powerlifting athletes.


2000 ◽  
Vol 122 (5) ◽  
pp. 541-544 ◽  
Author(s):  
W. G. Van Dorn

A thermodynamic heat flow model for the human body gives survival time as a function of water temperature, assuming constant specific heat and thermal conductance. [S0148-0731(00)01305-4]


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