Atc.ba

EUROPEAN ORGANISATION FOR THE SAFETY OF
AIR NAVIGATION
EUROCONTROL
This document is issued as EATCHIP Reference Material. The contents are not
mandatory. They provide information and explanation or may indicate best practice.
Human Factors Module
HUM.ET1.ST13.2000-REP-01
Edition Date
15.03.1996
Released Issue
EUROPEAN AIR TRAFFIC CONTROL HARMONISATION
AND INTEGRATION PROGRAMME
DOCUMENT IDENTIFICATION SHEET
DOCUMENT DESCRIPTION
Document Title
EWP DELIVERABLE REFERENCE NUMBER: HUM.ET1.ST13.2000-DEL.05.
PROGRAMME REFERENCE INDEX
EDITION :
EDITION DATE :
Abstract
This document is, within the Human Resources Domain, one of the Human Factors Modules. Thesemodules deal with Human Performance. This module explains human stress.
It describes the sources for stress, human reactions to stress and human perception of stress. Themodule further defines prevention & coping techniques, prevention in terms of selection, training,jobdesign, medical checks, attitudes and behaviour and coping in terms of recognition, food, exerciseand relaxation techniques.
Keywords
CONTACT PERSON :
TEL : 3566
DIVISION :
DOCUMENT STATUS AND TYPE
CATEGORY
CLASSIFICATION
ELECTRONIC BACKUP
INTERNAL REFERENCE NAME :
HOST SYSTEM
SOFTWARE(S)
DOCUMENT APPROVAL
The following table identifies all management authorities who have successively approvedthe present issue of this document.
AUTHORITY
NAME AND SIGNATURE
DOCUMENT CHANGE RECORD
The following table records the complete history of the successive editions of the presentdocument.
SECTIONS PAGES
REASON FOR CHANGE
AFFECTED
TABLE OF CONTENTS
DOCUMENT IDENTIFICATION SHEET . ii
DOCUMENT APPROVAL . iii
DOCUMENT CHANGE RECORD . iv
TABLE OF CONTENTS . v
EXECUTIVE SUMMARY . 1
INTRODUCTION . 3
STRESS REACTIONS. 5
2.1 Fight-flight response . 52.2 Stress hormones . 6 STRESS SOURCES. 7
3.1 Introduction . 73.2 Environment. 83.3 Body and thoughts . 123.4 Two dimensional theory of activation . 13 STRESS PERCEPTION . 15
4.1 Introduction . 154.2 Physiological symptoms . 154.3 Behavioural symptoms . 154.4 Symptoms in mental functioning . 164.5 Emotional symptoms. 16 HELPING OTHERS . 17
5.1 Phase 1 : Recognition . 175.2 Phase 2 : Emotional support . 175.3 Phase 3 : Logical support. 17 PREVENTION AND COPING . 19
6.1 Prevention. 196.2 Coping . 196.3 Relaxation techniques . 196.4 Autogenic-type exercise . 216.5 Understanding sleep . 23 REFERENCES . 25
EXECUTIVE SUMMARY
The EATCHIP Human Resources Domain develops several human factors modules thatdeal with the management of human performance. This module is about stress. The aim ofthis module is to present an overview, which will enable the reader to recognise stress, tounderstand stress and to cope with stress.
Chapter 1 explains that a certain amount of stress is essential to life and that too much ortoo little can lead to stress reactions. People have no absolute level of strain that producesstress. Stress occurs because of natural bodily mechanisms, a series of physiological andbiochemical changes.
Chapter 2 describes the three basic sources for stress, the environment, the body and themind. Environmental sources can be divided in conditions and events in work and private life.
People learn to cope with conditions, events can cause stress reactions. A list of measurablestress factors is added. The sources body and mind are explained by two theories.The firstdescribes different personality types and their typical stress reactions. The second theorydifferentiates two systems of activation, anxiety and energy, and explains the relationshipbetween these systems.
Chapter 3 covers the perception of stress. Four categories of symptoms are listed,physiological, behavioural, mental and emotional symptoms. Recognition of these symptomsis important because it helps in managing stress.
Chapter 4 shows how to react on emotional and rational level to a person who shows stresssymptoms.
Chapter 5 gives ways of prevention and coping, on individual and on organisational level.
The importance of sleep and relaxation is emphasised and dealt with in more detail in theparagraphs 3, 4 and 5 of this chapter.
References can be found at the end of the document.
1. INTRODUCTION
Stress is an everyday fact of life. You can't avoid it. It is caused by changethat you must adjust to. While you usually think of negative events which canevoke stress, such as injury, illness, or death of a loved one, they can also bepositive. For instance, getting a new home or a promotion brings with it thestress of change of status and new responsibilities. Falling in love can be asstressful for some people as falling out of love.
All stress is not bad. A certain amount of stress is not only desirable butessential to life. Not enough pressure can cause inactivity and you feel bored.
Too much pressure can cause that you can't cope, your work suffers, yousuffer. The right pressure can make you active and interested, you producegood work, you feel good.
What is experienced as stress varies between individuals and varies for thesame individual from time to time. In engineering, stress is defined as: "toomuch pressure". Unlike in engineering, people have no absolute level ofpressure that produces stress, stress comes in a variety of shades andshapes.
1.1 Scope
Within the EATCHIP Human Resources Domain the Human Factors Modulesseek to provide a better understanding of the factors that influence humanperformance. Stress is such a factor. A better understanding of what stress isand an improved insight in the positive and negative functions of stress lead tobetter application of prevention and coping techniques.
Stress management contributes in that respect directly to safety in air trafficmanagement.
1.2 Purpose
The aim of this module is to present an overview, which will better enable thereader to recognise stress, to understand stress and to cope with stress. Thisdocument is intentionally written in a style which is easy to read andunderstand. It should address operational staff in the execution of their job,trainers in the preparation of course content and documentation, andsupervisors in the management of hectic and stressful situations.
The reference material at the end of the document provides the interestedreader with further detailed documentation.
2. STRESS
REACTIONS
2.1 Fight-flight
response
Whether your stress experience is a result of major life changes or thecumulative effects of minor daily hassles, it is how you react to stressfulevents that determines degree and kind of your stress-response.
Stress reactions occur because of natural bodily mechanisms. The fight-flightresponse is described as a series of physiological and biochemical changesthat prepare us to deal with threats. This has already proofed valuable in pre-civilisation when primitive man needed, for example, quick bursts of energy tofight or flee wild animals. But in civilised society, when we get the samealertness-response, social custom prevents us from direct fighting or runningaway. So we have learned to apply indirect fight and flight behaviour.
What exactly happens in our brains and body when we show a fight-flightresponse? Figure 1: The human brain
This simplified figure shows the main parts of the brain of a Homo Sapiens.
The oldest part is the hypothalamus which some also call the reptile brainbecause we share it with crocodiles and other reptiles. If we are in athreatening situation this part of our brain quickly decides whether we shouldprepare our body to fight or to leave the situation as quickly as possible.
2.2 Stress
hormones
Another part of the brain, the limbic system, which is above the reptile brain,manages the emotions we perceive as likes or dislikes. These two parts of thebrain co-ordinate and send signals to our hormone system which increases ordecreases the amount of stress hormones in our blood circulation. We alwayshave a certain amount of these stress hormones in our body dictating activityand energy. But if the amount of stress hormones is over a certain thresholdwe tend to react through our reptile brain and sometimes the Homo Sapiensbecomes a Hormo Sapiens (one of the most dangerous animals). Typicalsymptoms are the increase of heart rate and blood pressure, diaphragm andanus locks, hands and feet get cold because the blood is needed by the largermuscles to prepare for fight or flight. The cerebral cortex, the youngest part ofthe brain, where all the logical thinking processes are located is covered in“psychological fog” - we are no longer able to think clearly and showreasonable behaviour. The perception of time changes, you will know fromyour own experience that pleasant events seem to pass quicker thanunpleasant ones. In fact, a person who is in a stressful unpleasant status hasmore time to “enjoy” it! The same mechanism that turned the stress response on can turn it off again.
After you decide that the situation is no longer threatening, your brain stopstriggering stress hormones. The hormones and chemicals are metabolisedand within three minutes the body stops sending emergency signals to yourreptile brain. The stress hormones of the fight and flight response burn outand you return to normal. Unfortunately, if the message to turn off the fight orflight response does not occur, a second response mechanism often is turnedon simultaneously, and if the biochemical and hormonal changes that happenduring the fight or flight response continue, chronic stress can result. Peoplewho suffer from chronic stress often develop typical psychosomatic symptomsand diseases like headache, migraine, back pain, digestive problems andhypertension (see also chapter 3: stress perception).
3. STRESS
3.1 Introduction
You experience stress from three basic sources : Your environment
Your environment bombards you with demands to adjust. You must endureweather, noise, crowding, interpersonal demands, time pressures,performance standards, unpredictable traffic load and various threats to yoursecurity and self-esteem.
Your body
The second source of stress is physiological. The rapid growth ofadolescence, menopause in women, ageing, illness, accidents, lack ofexercise, poor nutrition, shiftwork and sleep disturbances all tax the body.
Your reaction to environmental threats and changes also produce bodychanges which are themselves stressful.
Your thoughts
The third source of stress is your thoughts. Your brain interprets andtranslates complex events in your environment and body and determineswhen to push the panic button. How you interpret, perceive, and label yourpresent experience and what you predict for the future can serve either torelax or stress you. Interpreting a sour look from your boss to mean that youare doing an indadequate job is likely to make you anxious. Interpreting thesame look as tiredness or preoccupation with personal problems will not be asfrightening.
The influences from your environment will be dealt with in the first part of thefollowing chapter. In the second part we will look at two theories. One ofFriedman & Rosenmann (1970) about the influences of the differences inpersonality and one theory of Thayer (1989) which explains the dependencybetween anxiety and energy.
3.2 Environment
One useful way of looking at the sources of stress is to distinguish betweenconditions (relatively fixed, permanent circumstances that people have to copewith) such as unusual working hours or hot, noisy working conditions, andevents which occur suddenly, such as an organisational change or the deathof a colleague. And although we are concerned with the work setting, theseconditions or events can occur outside work too and can stress people(illness, disability or financial worries, for example). We can develop a simpleframework for these potential sources of stress like this : Table 1: Stress sources
3.2.1 Conditions
Table 1.1: Stress sources, conditions at work situations
The conditions at work with which we learn to cope, are relatively fixedcircumstances like job overload, either quantitative (too much work) orqualitative (too difficult), lack of control over work, lack of physical activity,extensive requirements to communicate, poor relations, responsibility forpeople, working hours and working conditions. Even unclear objectives orexpectations and role conflicts (like responsinility for high output and perfectquality) are conditions with which people learn to cope.
Table 1.2: Stress sources: Conditions at non work situations
Conditions in the private life can be things like family problems, livingconditions, financial difficulties and disability. And in relation to work there canbe conflicts between one’s own and the company’s values or between familyand company demands, and who doesn’t get irritated by the daily trafficproblems to and from work? Conditions are often unpleasant experiences but they are part of life, peoplelearn to cope with them.
3.2.2 Events
Table 1.3: Stress sources, events at work situations
Events can suddenly cause a stress reaction, their impact varies however perperson per situation. A rating scale of events is shown in the next paragraph.
At work we experience events like promotion (positive) or demotion (negative).
Other examples are reorganisation, disciplinary action, new tasks, a new bossor an accident.
Table 1.4: Stress sources: Events at non work situations
At home, or privately, we experience events like births, marriages and deaths.
But also marital disputes, illness or accidents are experienced as stressful andcan cause stress reactions.
The readjustment rating scale
Events vary in their potential impact. Holmes and Rahe (1967) havedeveloped a scale that is meant as a guide of measurable stress factors. Seethe rating scale at the next page, 100 = massive impact, 0 = no impact.
There are many other sources of stress, but it is true to say that a high score(300 or more) on this chart over a time span of six months or so, is a strongindicator of the likelihood of major stress syndromes and/or possible psycho-somatic diseases becoming apparent. A relatively high score (150 - 299) (overa period of 6 months) leads to stress afterwards for about 50 % of people.
Under 150 points (over a period of 6 months) fewer than 30 % of people It is known that these scores and the position on the scale of some of theevents, vary in different cultures. Different belief systems place the stress ofmarriage higher in Europe, for example than in Japan. It is also clear from thelist that stress factors are not necessarily unpleasant episodes. A marriage orholiday, for example, is seen as a cause of stress.
Change itself, pleasant or unpleasant, is therefore one potential factor forstress, but it is the response of the individual, his/her attitudes, beliefs andunderlying health status, that is the real determining factor in the effects ofstress.
Table 2: The social readjustment rating scale
Changes in lifestyle
Body and thoughts
Research strongly indicates that personality is an important factor in the stressresponse of an individual.
It is found that so-called type A personalities are more prone to stressedreaction than type B personalities.
It is possible for type A personalities to modify their behaviour, and by doingso to reduce their tendency to stressed reactions. Modification is achieved byselecting a particular characteristic and deliberately copy to opposite (type B)characteristic. For example, the quick eater should allow more time to eat andchew more slowly, until this has become a habit.
Around 40 % of the population are type A.
Age is also factor. Increasing age can lessen ability to cope with stress,although coping skills can be developed.
Table 3: Personality behaviour patterns
Type A personality
Type B personality
Relaxed facial muscles and doesnot clench fists Two dimensional theory of activation
Thayer(1989) developed the two-dimensional theory of activation. Hedifferentiates two systems of activation. One is called energetic arousal andcan be described in terms of energy, activity and readiness; it prepares thebody for movement and action. The other is called tense arousal and isassociated with feelings of fear and anxiety; it prepares the organism foractions and/or resistance and inhibition when dangerous situations areperceived.
The two dimensions are the basis for various emotional conditions.
Figure 2: Two dimensional theory of activation
The combination of higher energetic and lower tense arousal describes thestatus of well-being when we are awake and active to do something. Lowenergetic and low tense arousal is the level when we are relaxed or asleep.
The two other combinations can be described with the fight-flight reaction. Inunpleasant, threatening situations, where we tend to fight, we need a higherenergetic and higher tense arousal. The flight response however requires alower energetic and higher tense arousal.
4. STRESS
PERCEPTION
4.1 Introduction
Possible stress symptoms can be defined in four categories. Look forrelatively sudden, but recognisable changes in several of these symptoms.
There may be other causes than stress, especially for the physiologicalsymptoms.
4.2 Physiological
symptoms
4.3 Behavioural
symptoms
Symptoms in mental functioning
4.5 Emotional
symptoms
• dissatisfaction with work and/or life 5. HELPING
How to react to a person whose behaviour indicates stress ? Phase 1 : Recognition
The four categories of symptoms help in recognising the symptoms (seechapter 4). Focus on recent, sudden changes in behaviour.
Phase 2 : Emotional support
Communication is so much more than the words we say. They form only asmall part of our expressiveness as human beings. Research shows thatwords only determine 7 - 12 % of the impact and meaning of our message.
Our body language - posture, gestures, eye-contact - and our tone of voicedetermine the context in which the message is embedded, and representmore than 80% (!) of our message. The exact figures may differ in differentsituations, but clearly body language and tonality make an enormousdifference to the impact and meaning of what we say. In other words, we hearbest through our eyes ! We learned that a stressed person mainly reacts on his/her reptile brain, thepsychological fog causes that the logical thinking and acting is hindered to agreat extent. Responding on the emotional level is therefore the bestresponse. We can do so by showing open body language. Open arms, openlegs, a friendly smile, nodding the head, a touch on the shoulder, that's theway to show understanding.
Limit your verbal reactions in this phase to ‘hums’, ‘yes’ and short repetitionsor summaries of the words the other person uses. Mirror the person'semotions. You will notice that the person calms down, the psychological fogdisappears. Only then is it time to communicate on the logical level.
Phase 3 : Logical support
Your support in this phase is aimed at helping the other to find logicalsolutions. People very often find their own solutions. Help in formulating thecoping action is often appreciated. Ask: “What are you going to do about it ?” and summarise the planned action(s), that is the best help you can give.
It does occur that during the definition of solutions in phase 3 people fall backto phase 2, the emotional phase. Repeat your emotional support until the fogdisappears again, and only then return to the logical level for definition ofsolutions.
PREVENTION AND COPING
You can do a lot about stress. Decide what's really important to you, you arecapable of doing far more than you ever think! Here are two basic approachesto do something about stress. First there is prevention, designing the stressout. Then there is coping, finding ways to deal with stress.
6.1 Prevention
• Job training, the better a person is prepared for the job, the better he or • Job (re)design, state your objectives clearly, define your autonomy, be active in giving and receiving feedback and participate actively in thethings happening.
• Selection procedure including tests for stress resistance.
• Open, supportive attitude and behaviour.
6.2 Coping
• Recognise stress symptoms in self and others.
• Time management and prioritising, at the beginning of each day.
• One thing at a time, and deal with everything only once.
• Food : less calories, less fat, less sugar.
• Exercise : swim, walk, cycle, jog.
• Relaxation : breathing, time off and relaxation techniques ( see • Develop support systems: family, friends and/or workgroups.
6.3 Relaxation
techniques
We all need to learn our own ways of dealing with stress and anxiety, and thetensions they cause. Firstly, these are things that all of us suffer from - theyare a natural, inevitable part of our lives. The differences lie in how we copewith them, what is tolerable for one person is quite unbearable for another.
The ways in which they affect us in no way indicate our worth and quality as human beings, so there is great need for us all to become used to relaxing,slowing down and calmly becoming aware of how we are and what ourpriorities are. To avoid getting caught up in the confusion of events around usand of our own over-active minds.
Relaxation is not difficult - all we need to do is focus on the act of relaxing andignore all those distractions. All those important matters that occupy our mindscan still be attended to, after we have given ourselves these precious 'timeout' sessions.
In order for relaxation to work, we need to create the right setting. Somewherequiet without disturbance, where ideally, we can lie down full-length, if theroom can be darkened so much the better. Having established ourselves in acomfortable position - if lying down is a problem, sitting with the backsupported will do at a pinch.
Mental and bodily awareness are crucial in relaxation, we can only change ifwe know how we feel. So check out how your body feels. Are you quitecomfortable? Snuggle down and settle your body so that it feels limp. Noticeyour mental state, are you tense or nervous, is your head full of thoughts. Allof this is quite normal, but whilst practising relaxation, you will learn to turnyour attention away from all this and just focus on relaxing.
The main ingredient of relaxation is breathing slowly and deeply from theabdomen, so as you commence breathing, place one hand on the upper chestand the other on the stomach, just below the ribcage. Concentrate on thebreath filling your lungs from the abdomen upwards. There should be as muchmovement there as from the chest. Getting into the habit of this style ofbreathing is quite important as when we breath slowly, using only the upperchest, this can actually add to our feelings of anxiety.
As you settle into this vital aspect of the relaxing process, it is useful whenbreathing out to imagine that you are letting go all of your worries andtensions. Continue with this style of breathing for about 3/4 minutes andwhenever you find your attention wondering, gently bring it back. You willnotice that the distractions of thoughts and 'noises off' will gradually lessen.
6.4 Autogenic-type
exercise
True autogenic exercises need to be taught by a special teacher orpractitioner, well versed in this excellent system. The modified methodoutlined below is based on the work of Schultz (1932), the pioneer in this field.
The distinction between a relaxation exercise and a meditation technique isblurred at all times, but never more so than in autogenic methods which are ablend of the two. At least fifteen and ideally twenty minutes should be given tothe performance of this method. At another time of the day, this or anotherrelaxation method should also be performed. This routine should become awelcome, eagerly anticipated oasis of calm and peace in the dailyprogramme. Stress-proofing, without such periods of 'switching off', is notlikely to be successfully achieved.
A reclining position should be adopted, with the eyes closed. External,distracting sounds should be minimised. The exercises involve the use ofspecific, verbalised messages to focus awareness on a particular area. Noeffort is involved, but simply a passive concentration on any sensations oremotions which may result from each message. Imagination orautosuggestion has been found to have definite physiological effects. Bycombining a sequence of autogenic (i.e. self-generated) instructions with thepassive, focused aspect of meditation techniques, a powerful method of self-help has been created.
The exercise starts with a general thought, such as 'I am relaxed and at peacewith myself'. Begin to breathe deeply in and out. Feel the light movement ofthe diaphragm and feel calm.
Stage I : The mind should focus on the area of the body to which the thought
is directed. Start by silently verbalising 'my right arm is heavy'. Think of the
image of the right arm. Visualise it completely relaxed, and resting on its
support (floor, arm of the chair, etc.). Dissociate it form the body, and from
will-power. See the limp, detached arm as being heavy, having weight. After a
few seconds the phrase should be repeated. This should be done a number of
times, before proceeding to the right leg, left leg, left arm, neck, shoulders and
back. At each area, try to sense heaviness and maintain a passive feeling in
the process.
Stage II : Again, begin with the right arm, concentrating on it as you silently
verbalise 'My right arm is warm'. Repeat this and pause to sense warmth in
the arm or hand. Repeat this several times. The pause should be unhurried.
To encourage this feeling of warmth, it may be useful to imagine that the sun's
rays are shining onto the back of the hand, warming it. The sensation of
warmth spreads from there to the whole arm. Proceed through all areas of the
body, pausing for some seconds at each to assess sensations which may
become apparent. Such changes as occur cannot be controlled, but will
happen when the mind is in a passive, receptive state. This exercise
increases the peripheral flow of blood, and relaxes the muscles controlling theblood vessels. It is possible to measurably increase the temperature of anarea of the body, using these simple methods.
Stage III : This focuses on the breathing cycle with the phrase 'My breathing
is calm and regular'. No conscious effort should be made to control the
breathing. Unlike the form of breathing used in the exercise, this involves a
passive approach. You should direct your concentration to the slight, even
motion of the diaphragm. Nothing should be consciously done about the
breathing, which should be completely automatic. Sometimes the verbalised
statement can be altered to 'The breathing is calm', or 'I am being breathed',
to good effect. Sometimes, quite unconsciously, a deep breath is taken during
the otherwise shallow breathing. This is quite normal. Nothing should be done
to control the pattern. Simply repeat the chosen phrase, and passively
observe and experience the sensations that accompany it. Slow repetition of
the phrase promotes deep, slow, regular breathing without effort. Continue for
several minutes, repeating the phrase periodically.
Stage IV : The phrase 'My forehead is cool' is repeated for several minutes.
This appears to produce a combination of alertness and relaxation. When
repeating this phrase, with suitable pauses, try to sense the coolness as a
pleasant sensation.
Stage V : The phrase 'I am alert and refreshed' ends the exercise. Breathe
deeply, stretch, and continue the day's activities.
During stages I and II, the time in each area should not be less than abouthalf a minute; it is, however, quite permissible to spend two or three minutesfocusing on any one part, especially if the desired sensation of heaviness orwarmth is achieved.
It will probably be found that the desired sensation is more easily sensed inone stage than another, and that some areas seem more 'responsive' thanothers. This is normal. It is also quite normal for there to be no subjectiveappreciation of any of the verbalised sensations. Do not worry about this.
Even if nothing at all is sensed for some considerable time, even somemonths, there is a great deal actually taking place within the body as a resultof the whole exercise. Persistence, patience and a total lack of urgency is allthat is necessary for this method to lead to a decrease in muscular tensionand a sense of calm and well-being. A 'side-effect' of this particular method isfrequently experienced in terms of much improved peripheral circulation, i.e.
an end to cold hands and feet! 6.5 Understanding
Sleep is a great healer. It regenerates your body, clears emotional conflictsand helps you think and work at top efficiency. It is another form of relaxation,essential to health and well-being. It must be admitted however, that in manyways, sleep remains a mystery despite much research and investigation.
Many of our ideas and notions about it are not accurate. For instance, it is nota kind of 'small death' from which we are rescued, upon wakening, eachmorning. Nor after going to sleep do we fall into a deeper and deeper slumberuntil we reach some 'deep sleep bottom'. Deep sleep is no more beneficialthan a light slumber. A fact of particular interest is that we do not always need8 hours a night to remain well, energetic and fresh looking. The amount ofsleep we do need will vary enormously from person to person and depend oncircumstance.
Sleep provides us with a balanced system of well adjusted hormones. Manyhormones are secreted into the body at night. When considering your sleepneeds, think about how energetic you are during the day, is your sleepdisturbed by discomfort, noise or being worried about anything. Your diet andeating habits will also have some influence on how well you sleep. Forinstance, a rich or heavy meal late in the evening could well cause indigestion.
Stimulants like tea, coffee or alcohol are best avoided by poor sleepers.
Alcohol may initially put you to sleep, but can cause you to wake in the earlyhours.
Obviously the practice of relaxation during the time before going to bed, willalways be beneficial. Above all, it is important not to worry aboutsleeplessness - so you can't get to sleep - maybe you are not yet ready to goto sleep, but just need to lie quietly or even do some low stress activity - likereading or listening to music.
Other aids to sleeping that you might like to try are: a milky drink (but avoidtea, coffee or cacao), a lukewarm bath, submerging as much of yourself aspossible for about 10 minutes. Avoid hot water as this can be too stimulatingto the heart.
REFERENCES
Friedman M., Byers S.O., Rosenman R.M., Newman R. (1970): CoronaryProne Individuals (Type A behaviour pattern), in: Journal of the AmericanMedical Association 217.
Holmes T.H., Rahe R.H. (1967): The Social Readjustment Rating Scale, in:Psychosomatic Medicine 11.
Hopkin V.D. (1995): Human Factors in Air Traffic Control.
Glass D.C. (1977): Behaviour Patterns, Stress and Coronary Disease. Jacobson E. (1938): Progressive Relaxation. University of Chicago.
Kanner A.D. et al. (1981): Comparison of two modes of stress measurement:Daily hassles and uplifts versus major life-events, in: Journal of behaviouralMedicine 4.
Rahe R.H. (1978): Editorial): Life Change Measurement Clarification, in:Psychosomatic Medicine 40.
Schultz T.H. (1932): Autogenic training, concentration and self relaxation,Stuttgart, Thieme.
Stokes A. and Kite K. (1994): Flight Stress: Stress, Fatigue and Performancein Aviation. Thayer R.E. (1989): The Biopsychology Mood and Arousal.

Source: http://www.atc.ba/doc/Stress.pdf