Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
The effects of cold water immersion on the body’s ability to perform dexterity tasks that can aid survival. Falmouth Marine School, Thomas D. Batchelor, 2012
Raising awareness for the hazard of a man overboard situation in cold water seas.
Thomas D. Batchelor Carinthia Weston Road Totland Bay Isle of Wight PO29 0HA 07792312602 Tombatchelor1002@hotmail.co.uk
1
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
ABSTRACT Cold water immersion is a very real hazard for all water users in Britain; it can kill regardless of how competent one is as a swimmer as it is not hypothermia that causes the most fatalities, but is in fact drowning due to the colds effect on the body’s muscles. Sever cold will restrict the muscles ability to function, and as a result, swimming becomes an impossible task. However, it is also clear that drowning is often the main cause of death following cold water immersion, as opposed to hypothermia. There is a general consensus of naivety, from the general public, when it comes to just how dangerous cold water immersion is, especially seeing as forty percent of drowning victims are children aged less than four years old; making drowning the second most common cause of accidental death amongst children (Orlowski, 1987). This experiment used a selection of asymptomatic students of 16-25 to investigate the body’s ability to perform dexterity tasks, when subject to cold water immersion, that can aid survival; using a VHF radio or signal flare. It was completed in a controlled environment, with the participants volunteering to be subject to mild hypothermia throughout the experiment. The subject would therefore witness first hand, how hard it is for the body to function when subject to such intense cold; especially in the hands or fingers. The results showed that the time taken to complete a safety task increased and became more difficult as the subject spent nearer 5 minutes in water of 10 degrees Celsius. This would mean that there is a limited amount of time that one can spend immersed in cold water before it is not only just their fingers that stop functioning with ease, but also larger body parts responsible for keeping one afloat or swimming after a man overboard situation. Conclusions The practical applications of the data gathered from this experiment are of course marine industry or maritime linked. They are to educate water users of the dangers of cold water
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Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
immersion, to provide safety advice and basic survival knowledge to the general public on water safety, to further educate professionals in the marine sector of the general perception to cold water immersion awareness and to assist in the risk assessment of situations where cold water immersion is a very real hazard. For example, to reiterate the importance of a personal flotation device in aiding cold water immersion survival, especially at water sport centres across the country. Keywords: Hypothermia. Cold Water Immersion. Cold Water Shock. Dexterity Tasks
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Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
INTRODUCTION H0. There will be no significant difference between time spent immersed in cold water and time taken to complete dexterity task. H1. There will be a significant difference between time spent immersed in cold water and time taken to complete dexterity task. A study conducted by the RNLI in 2008 brought to reality the very real hazard of death by drowning in the United Kingdom (UK), and the main harsh reality of the matter was that “approximately 1,500 people drown in the UK per year” however, the worrying statistic was that only “25% of these drowning occur at sea”. This means that up to 75% of reported drowning did in fact occur in water situated in land; areas like lakes, rivers, reservoirs etc; the ideal locations where water sport centres thrive best as businesses in the UK. Such are the threats of cold water immersion at these locations, that ignorance to water safety is thoroughly unacceptable; as such, the importance of this study is indeed relevant when considering a practical application to help promote water safety to the general public and marine industry; water safety such as flotation devices for inexperienced water goers and properly completed risk assessments for water sport centres. Wissler (2003) also stresses the importance of personal flotation devices (PFD’s) and goes on to say that flotation is an absolute requirement for survival; these ideas are backed up by Higenbottam (1995) and Jacobs (2008). The alternate hypothesis, “There will be a significant difference between time spent immersed in cold water and time taken to complete dexterity task”, can be further developed to state that the cold water immersion will decrease the overall body temperature and thus making muscular movement more difficult to complete. This increase in difficulty to move whilst immersed can be significantly linked with finer, dexterous movement, such as; moving ones fingers to use a VHF radio to signal for help in a man overboard situation, or sinking of a craft etc. It is fact that the
4
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
areas of the body situated furthest away from the core are the first to lose heat and the first be subject to slow blood flow carrying oxygenated blood to working muscles. It is deemed necessary for the core to have the majority of the oxygenated blood sent to it, so to keep vital organs safe and surrounding muscles working to keep generating heat. However, as fingers, toes, arms, ears, nose and legs are the first parts of the body to start feeling cold (Tipton, 1989) and that it is in fact these parts of the body, especially hands, legs and arms that play the majority gross muscle movers in swimming, or staying afloat, it is clear to see just how bad of an effect cold water can have in restricting muscle movement. There are many survival tips that the marine industry are aware of and have produced, however, as far as survival tips for the general public go, it is naively considered a specialist situation, when statistics prove that death by cold water immersion is a far too common occurrence which can be avoided and prevented. Cheung et al (2003) provides advice to any victim of cold water immersion to reduce the danger affiliated with the cold water shock; by controlling their breathing for the first 3-5 minutes prior to attempting escape, the strain on the cardiac muscle and the effect from the aspiratory gasp with relation to aspiration of fluid into the lungs are controlled. This study will hopefully bring to light just how quickly cold water immersion can restrict the body’s ability to function and as such result in chances of survival being drastically reduced.
5
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
METHODS Experimental approach to the problem To simulate how the body reacts in cold water immersion, firstly a body of water in a controlled environment must be attained, this body of water must be safe and have no additional variables that may reduce the validity of the test or any such results gathered from the test. To test the hypothesis, a tank of water (1meter wide x 1 meter deep x 7 meters long) was filled with water with a temperature of 10 degrees Celsius as this would be a controlled environment with absolutely no risk of drowning for the participant as long as safety cover was at hand to assess the subject’s welfare conditions. The extended duration of time spent in the cold water would result in the subject experiencing all changes and body adaptations that a person who has actually fallen into cold water would feel; all except possibly the factor of fear, which would be eliminated for the purpose of a valid, ethical and controlled test. The simple dexterity task would then be used as the physical indicator on how much the body is affected by cold water immersion, which would then be measured and analysed alongside the scientific reading of the subject’s actual body temperature. By controlling all outside variable that a person would experience in a real cold water immersion situation, such as wind chill, water current and the presence of swimming, it is a clearer indication on how cold water alone effects the body’s functioning ability and just how little variables are needed to place someone in a life and death situation. In addition, clearer recommendations can be made regarding safety awareness that takes into account how long the body can resist the cold up to the point where the subject in succumbed to the cold no longer has the ability to move body parts. Subjects “Table 1” shows the list of asymptomatic students from Falmouth Marine School, within the ages of 18 to 24 of both sexes that had consent to participate in the experiment. All willingly signed 6
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
a consent form and were allowed to withdraw from the experimentation process at any point, no subject had any medical condition that may interfere with the results and no subject had any practise in the dexterity task, used as the main test of cold water restriction on the body, before the experiment, so performance enhancing by practise could not occur at the initial stages of testing. Table 1 Participant Number
Name
Sex
Age
Height (CM)
Weight (KG)
1
Benjamin Tun Pe
M
21
167.64
63
2
Leon Vessey
M
19
177
72
22.98 kg/m
2
(Healthy weight)
3
Josh Neely
M
19
181
65
19.84 kg/m
2
(Healthy weight)
4
Katie Buddoch
F
18
5
Josh Burgon
M
21
6
Tom Greaves
M
19
7
Georgia Thompson
F
18
8
Edward Jones
M
18
9
Richard Smith
M
18
10
Callum Knight
M
18
11
Chris Garbet
M
18
12
Thomas Batchelor
M
19
182.88
73
21.83 kg/m
2
(Healthy weight)
13
Alex Sawdon
M
19
14
William West
M
24
179.4
75
15
William Stitson
M
20
162.4
69.85
16
Daniel Flint
M
22
17
Craig Stearman
M
21
18
Elliot Shilling
M
19
7
BMI
22.42 kg/m
23.30 kg/m 21.48 kg/m
2
2
2
(Normal)
(Normal)
(Healthy weight)
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
Equipment List
Water tank (7m x 1m x 1m) filled with water of 10 degrees Celsius
Indoor location (protected from the wind) with an air temperature of 14 degrees Celsius
“Vicks” Digital Thermometer for oral use
Deactivated handheld VHF Radio
Stopwatch x2
Swimming costumes (standard swimming apparatus, shorts for males, bikini’s for females)
“Gull” water proof overalls trousers
“Gull” water proof overalls jacket
Towel
Dry clothing
First aid kit
Foil Blankets
Procedures 1. Subject to get changed into swimming clothing 2. Subject to get changed into waterproof overalls 3. Subject’s body temperature to be measured using the digital thermometer 4. Subject to be briefed for a second time (initial brief is stated on consent form) on to what the experiment is and what they will experience: i. Participant will enter the water, fully immersing themselves in the water, then to lie on their back in the water for 5 minutes. They will then be asked to complete the dexterity test on the 1 minute, 3 minute and 5 minute marker, before they can exit the water slowly and safely. 5. Subject is given practical tutorial on how to conduct initial dexterity test i. Press the channel 16 button 8
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
ii. Adjust the squelch iii. Press and hold the communication button and say the following phrase in a clear and concise manner: iv. “Coastguard Coastguard Coastguard� 6. Subject is to stand on the side of the tank and enter the water quickly so as to submerse for a brief moment of time, to simulate falling overboard into the water. 7. Subject the lays on their back in the water with VHF in hand 8. Timing begins as soon as the subjects head is under the water. Timing to last 5 minutes. 9. Subject remains in water for one minute with hands fully immersed in water 10. Body temperature to be taken orally after one minute of immersion is reached 11. Result to be recorded 12. Subject is told to complete VHF dexterity task and timed 13. Time of task to be recorded 14. Subject is then to rate on a scale of 1 to 10 (1=easy & 10=difficult) how easy it was to perform task. 15. Rating to be recorded 16. Points 10 through to 15 are repeated on the 3 minute mark and on the 5 minute mark 17. Throughout experiment, first aider is to monitor visual signs of hypothermia 18. Subject is also to be reminded throughout the test that they can exit the water at any time 19. After the results for the 5 minute data is recorded the subject may exit water by simply standing up and stepping out of the tank slowly and carefully with assistance if needed. 20. Drying and reheating precautionary measures are then given to the subject to help slowly warm up the body 21. This whole process is then repeated for all 18 participants that volunteered for the experiment.
9
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
Statistical analysis The data gathered from the above experiment will be statistically analysed using a T-test with a significance level of 0.05 being used. The mean age of the group will be calculated, along with the mean body temperature and time taken to complete dexterity task for the control, at 1 minute in the water, 3 minutes and 5 minutes. The means will serve as a more ecologically valid and less generalised sample group data. Furthermore, it makes the statistical analysis using a T-test more relevant to reach a significance level.
10
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
RESULTS Table 2 shows the results of the participants’ body temperature, in degrees Celsius, for the control and over 5 minutes immersed in cold water. The hypothesis would predict that the longer spent in the water, the lower the body temperature will drop; however, due to the nature of the experiment and the time spent in the water, the participant’s body temperature would not decrease to a number around the severe mark as stated by Kernshaw (2002), which is that “any persons immersed in cold water...if reaching a body temperature read out of 24-26 degrees Celsius then death is going to occur”. Kernshaw’s justification of cold is as follows:
37 °C (99 °F) - Normal body temperature (which varies between about 36–37.5 °C (97–100 °F))
36 °C (97 °F) - Mild to moderate shivering (body temperature may drop this low during sleep). May be a normal body temperature.
35 °C (95 °F) - (Hypothermia) is less than 35 °C (95 °F) - Intense shivering, numbness and bluish/grayness of the skin. There is the possibility of heart irritability.
34 °C (93 °F) - Severe shivering, loss of movement of fingers, blueness and confusion. Some behavioral changes may take place.
33 °C (91 °F) - Moderate to severe confusion, sleepiness, depressed reflexes, progressive loss of shivering, slow heart beat, shallow breathing. Shivering may stop. Subject may be unresponsive to certain stimuli.
32 °C (90 °F) - (Medical emergency) Hallucinations, delirium, complete confusion, extreme sleepiness that is progressively becoming comatose. Shivering is absent (subject may even think they are hot). Reflex may be absent or very slight.
31 °C (88 °F) - Comatose, very rarely conscious. No or slight reflexes. Very shallow breathing and slow heart rate. Possibility of serious heart rhythm problems.
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Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
28 °C (82 °F) - Severe heart rhythm disturbances are likely and breathing may stop at any time. Patient may appear to be dead.
24–26 °C (75–79 °F) or less - Death
Due to the nature of this experiment however, the mean body temperature for the group did not reach lower than 35.9°C, with lowest single results not dropping under 35.2°C; this means that all participants were safe as long as safety cover was at hand to assess the mild hypothermic conditions that some subjects may have been subdued to. Table 3 shows the time taken to complete the VHF signal call (dexterity task) and what was expected from the hypothesis was that as time immersed in cold water increases, so would the time taken to complete the dexterity task. This part of the experiment was the key factor in looking at how the body’s functioning ability is affected by the cold. It is then given a qualitative backing from table 4 which shows the subjects own personal assessment of the conditions they are experiencing and their analysis of their own performance on the task.
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Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
Table 2
Participant no. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Control 36.4 36.2 36.7 36.4 36.4 36.8 36.9 36.5 36.4 36.1 36.5 36.4 36.1 36.5 36.4 36.6 36.6 36.2
Mean
36.5
Body Temperature (â °C) 1min 3min 36.4 36.3 36.2 36.1 36.5 36.4 35.8 35.6 36.4 36.3 36.4 36.1 35.3 35.3 36.5 36.3 35.9 35.5 35.3 36.1 36.2 35.9 36.2 36.1 35.9 35.8 36.2 36.1 36.3 36.2 36.4 36.4 36.4 36.1 36.2 36.1
5min 36.2 36 36.2 35.4 35.8 36 35.2 36.1 35.3 35.9 35.8 35.8 35.6 36.1 36.0 36.4 36.1 35.7
36.1
35.9
36.0
Body Temperature Results
Body Temperature (Celcius)
37.5 37 36.5 36
Control 1min
35.5
3min
35
5min
34.5 34 1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18
Participants Figure 1
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Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
Time Taken to Complete VHF Task 5 4.5 Time Taken (Seconds)
4 3.5 3
Control
2.5
1min
2
3min
1.5
5min
1 0.5 0 1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18
Participants Figure 2
Table 3
Participant no.
14
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Control 2.97 1.93 2.44 2.19 1.97 1.53 2.57 2.05 2.66 2.37 2.69 1.67 2.68 2.75 2.21 2.59 2.59 2.84
Mean
2.372222
Time taken for VHF Task (S.MS) 1min 3min 3.22 3.88 2.84 2.89 2.15 2.78 2.47 2.5 2.69 2.81 2.18 2.5 2.03 3.19 2.68 3.13 3.44 4.08 3.69 4.34 2.72 3 2.7 3.09 2.69 2.25 2.35 2.16 3.23 2.8 2.6 3.22 2.94 3.09 3.7 2.68
2.795556
3.021667
5min 4.57 2.98 2.91 3 2.99 2.99 3.5 2.48 4.47 4.66 3.09 4 2.58 2.35 2.81 2.25 2.35 2.63
3.145
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
Table 4
Participant no.
Own Performance rating (n/10) 1min 3min 5 6 5 8 3 5 3 4 4 6 4 5 5 8 6 8 6 9 6 7 4 6 4 8 4 6 5 5 5 7 6 7 5 6 5 7
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Control 3 2 2 2 2 1 3 2 3 3 1 2 1 2 2 2 2 2
Mean
2.055556
4.722222
5min 3 2 2 2 2 1 3 2 3 3 1 2 1 2 2 2 2 2
6.555556
2.055556
Self Assesment of Performance 10 9 8 Rating 1-10
7 6 5
1min
4
3min
3
5min
2 1 0 1
2
3
4
5
6
7
8
9
10
Participant
Figure 3
15
11
12
13
14
15
16
17
18
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
DISCUSSION The results show that the mean body temperature of each participant decreased from 36.5°C to 35.9°C, this is definitely a case for the longer the amount of time spent in the cold water, the more the body’s temperature will decrease, thus resulting in the subject entering more dangerous stages of hypothermia. The participants that showed the lowest body temperature at the end of the 5 minute immersion were subjects 4, 7 and 9; who coincidently are the two female participants and the youngest male participant. The remaining participants showed a much better result of around 36°C; this is evidence for males, with a larger body composition being able to keep thermoregulation at a steadier pace than females with smaller body compositions and less muscle mass. The results of the three lowest body temperatures can be seen against the three highest body temperatures in figure 4, figure 4 shows that there is a noticeable difference between the top three temperatures and the bottom three temperatures, which means that body composition, sex and age may be the most likely factors to keeping a steady thermoregulatory heat loss. Interestingly however, it is the female participant (participant 7) who starts with the highest body temperature before entering the water; who then ends up with lowest body temperature. The sever loss of heat may be due to what is known as the cold water shock; Wissler (2003) reports that in a fraction of accidental immersions, death may occur quickly owing to cold water shock due to the stressed character of the casualty.
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Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
Figure 4
Three Highest Body Temperatures against Three Lowest Temperatures Body Temperature (celsius)
37.5 37 36.5
4
36
7
35.5
9 1
35
3
34.5
16
34 Control
1min
3min
5min
Time
The mean time taken for the completion of the dexterity task, starting at control and ending after 5 minutes of immersion, increased from 02:37 (SS:MS) to 03:14 (SS:MS), this increase in time positively backs up the hypothesis that the muscles are being hindered by the effects that the cold water is presenting. Figure 5 shows the three participants that completed the task the quickest at the end of their 5 minute immersion against the participants that took the longest times; this shows that participants 1, 9 and 12 noticed a more significant effect, or succumbed to the cold in a more noticeable manner, in their body’s ability to complete the dexterity task. Whereas, participants 14, 16 and 17 managed to keep their fingers moving in a more efficient way as the cold was setting in. The three slowest participants all showed a constant increase in time, which shows that the cold was indeed having an effect as time went on; however, the results for the three fastest showed interesting anomalies in the data. Participant 14 shows a decrease in time from the control to the 3rd minute, then an increase up to the 5th minute, which suggests that the cold did indeed affect this participant after extended immersion; however, the reasoning for the decrease in time at the start of the experiment could be the practise effect, which means that the participant knew what to
17
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
expect, kinaesthetically, in terms of the dexterity task. In relation to participants 16 and 17, the practise effect has also seemed to have occurred during the 5th minute however, which definitely suggests that the cold had not affected their fingers in the same physiological way that it did for the slowest participants. Figure 5
Three Longest Task Completions against Three Shortest Task Completions 5
Time Taken (seconds)
4.5 4 3.5
1
3
9
2.5
12
2
14
1.5 1
16
0.5
17
0 Control
1min
3min
5min
Time Stage
After using “mini tab� for the statistical analysis of my data means, there is definitely a significant difference between the relationship of body temperature and time taken to complete the dexterity task. This means that the null hypothesis can be rejected and that the time spent immersed in cold water will in fact increase the time taken to complete the dexterity task. In addition, it proves that cold water has a sufficiently dangerous effect on the body’s functioning ability, which can of course result in drowning and hypothermia. After an analysis of these results, it is surprising to see just how short the amount of time a subject needs to spend in cold water, deemed an average water temperature for most of the bodies of water in the United Kingdom, before noticeable effects are seen.
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Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
From assessing the results, the recommendations that can be made for all practical applications are that cold water immersion should be avoided at all costs, unless professional measures are taken, e.g. wearing a winter wetsuit and a personal flotation device. As far as a man over board situation is concerned, it is a reasonable action to suggest that all maritime or marine professionals in the industry should be wearing personal flotation devices when the threat of cold water immersion is a very real hazard, due to the short amount of time needed for the body’s functioning to succumb to the cold, and drowning to become a reality.
2-Sample t Test for the Mean of Body Tempera and Time taken f Summary Report Statistics
Do the means differ? 0
0.05 0.1
> 0.5
Yes
No
P = 0.000 The mean of Body Tempera is significantly different from the mean of Time taken f (p < 0.05).
Sample size Mean 95% CI Standard deviation
Body Tempera
Time taken f
4 36.113 (35.73, 36.49) 0.23936
4 2.8336 (2.2927, 3.3745) 0.33993
Difference between means* 33.279 95% CI (32.745, 33.813) * The difference is defined as Body Tempera - Time taken f.
95% CI for the Difference Does the interval include zero? Comments 0
10
20
-- Test: You can conclude that the means differ at the 0.05 level of significance. -- CI: Quantifies the uncertainty associated with estimating the difference from sample data. You can be 95% confident that the true difference is between 32.745 and 33.813. -- Distribution of Data: Compare the location and means of samples. Look for unusual data before interpreting the results of the test.
30
Distribution of Data Compare the data and means of the samples. Body Tempera
Time taken f
0
19
10
20
30
40
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
2-Sample t Test for the Mean of Body Tempera and Time taken f Diagnostic Report Data in Worksheet Order Investigate outliers (marked in red). Body Tempera
Time taken f
30
20
10
1
2
3
4
60%
90%
2
3
4
What difference can you detect with your sample sizes of 4?
Power What is the chance of detecting a difference? < 40%
1
100%
Difference
Power
0.56216 0.63319 0.71690 0.83402
60.0 70.0 80.0 90.0
0.56216 0.83402 For alpha = 0.05 and sample sizes = 4: If the true means differed by 0.56216, you would have a 60% chance of detecting the difference. If they differed by 0.83402, you would have a 90% chance.
Power is a function of the sample sizes and the standard deviations. To detect a difference smaller than 0.71690, consider increasing the sample sizes.
2-Sample t Test for the Mean of Body Tempera and Time taken f Report Card Check
Status
Unusual Data Normality
Sample Size
20
Description There are no unusual data points. Unusual data can have a strong influence on the results.
!
Because the sample sizes are less than 15, normality can be an issue. If the data are not normally distributed, the p-value may be inaccurate with small samples. Because normality cannot be reliably checked with small samples, you should use caution when interpreting the test results. The sample is sufficient to detect a difference between the means.
Thomas Batchelor
FdSc Marine Sport Science - Project
2012/04/20
References 1. Brajkovic, D. & Ducharme, M.B. (2003) Finger dexterity, skin temperature, and blood flow during auxiliary heating in the cold. Journals of Applied Physiology; 95: 758-770 2. Cheung, S.S. Monte, D.L. White, M.D. & Behm, D. (2003) Changes in Manual Dexterity Following Short-Term Hand and Forearm Immersion in 10â °C Water. Aviation, Space and Environmental Medicine; Vol. 74, No 9: 990-993 3. Deighton, L. (1993) Blood, Tears, and Folly: An Objective Look at World War II. New York: Harper Collins 4. Flouris, A.D. Cheung, S.S. Fowles, J.R. Kruisselbrink, L.D. Westwood, D.A. Carrillo A.E. & Murphy, R.J.L. (2006) Influence of body heat content on hand function during prolonged cold exposures. Journals of Applied Physiology; 101: 802-808 5. Golden, F.S.C. Tipton, M.J. & Scott, R.C. (1997) Immersion, near-drowning and drowning. British Journal of Anaesthesia; 79: 214-225 6. Goodall, S. & Howatson, G. (2008) The effects of multiple cold water immersions on indices of muscle damage. Journal of Sport Science and Medicine; 7: 235-241 7. Higenbottam, C. (1995) The risk of drowning for immersion victims wearing lifejackets
in
rough
water.
Defence
Research
Agency;
Report
No:
DRA/CHS(Hs2)/CR95/071 8. Jacob, M. (2008) Cold-Water Immersion. Wilderness Medicine magazine; Vol. 25, No. 3: 6-7 9. Keatinge, W.R. Nadal, J.A. (1965) Immediate respiratory response to sudden cooling of the skin. Journal of applied physiology; 20: 65-69 10. Knight. Horvarth, S.M. (1985) Urinary responses to cold temperatures during water immersion. American Journal of Physiology; 248: 560-566 11. Modell, J.H. (1993) Drowning. New England Journal of Medicine; 328: 253-256 12. Orlowski, J.P (1987) Drowning, near-drowning and ice-water submersions. Paediatric Clinics of North America; 34: 75-92
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FdSc Marine Sport Science - Project
2012/04/20
13. Orlowski, J.P (1988) Drowning, near-drowning and ice-water drowning. Journal of the American Medical Association; 260: 390-391 14. Paton, B. (2001) Cold, casualties, and conquests: The effects of cold on warfare. Medical Aspects of Harsh Environments: 311-349 15. Pozos, R.S (2003) Nazi Hypothermia Research: Should the data be used? Military Medical Ethics; Volume 2: 438-444 16. Stein S, trans. Partial translation of document 1602-PS. Letter from Dr. Rascher to Himmler requesting use of prisoners for high altitude experiments. Source: Nazi Conspiracy and Aggression, Vol. 4. Washington, DC: US GPO; 1946. 17. Steinman, A. & Giesbrecht, G. (2001) Cold-Water Immersion. Wilderness Medicine; 4th edition: available from: http://www.experts.com/Articles/Immersion-Into-ColdWater-By-Dr-Alan-Steinman 18. Tipton, M.J. Golden, F.S.C. Higenbottam, C. Mekjavic, I.P. Eglin, C.M. (1998) Temperature dependence of habituation of the initial responses to cold-water immersion. European Journal of Applied Physiology and Occupational Physiology; Volume 78, Number 3: 253-257 19. Wissler, E.H. (2003) Probability of Survival During Accidental Immersion in Cold Water. Aviation, Space and Environmental Medicine; Vol. 74, No1: 47-55 20. Wittmers, L.E. & Savage, M.V (1996) Cold Water Immersion. Medical Aspects of Harsh Environments; Vol. 1: 531-555
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