Pratique du Shadowing: Fever Feels Horrible, but is Actually Awesome! - Apprendre l'anglais à l'oral avec la vidéo
Création de la leçon...
1
Fever feels bad, so we take medication to suppress it.
2
But is this a good idea?
3
It turns out fever is one of the oldest defenses against disease.
4
What exactly is it?
5
How does it make your immune defense stronger?
6
And should you take a pill to combat it?
7
The heat of life.
8
On Earth, life is able to thrive between the extremes of minus 10 degrees Celsius in deep cool pools
9
and 120 degrees Celsius in thermal vents.
10
Step outside this range and die.
11
Every animal or microbe has a temperature range that's ideal and one that's stressful but survivable for a while.
12
Your ideal temperature is where your cells work best, where their internal machinery is the most efficient and the animal as a whole the best adapted to its niche.
13
are warm-blooded animals and our bodies expend a lot of energy to keep us around 37 degrees Celsius or 98.6 degrees Fahrenheit.
14
Which seems wasteful, but this may actually be a defensive adaptation.
15
Our temperature makes us almost entirely immune to one of the worst killers and parasites, fungi.
16
Most colder animals and their insides are infected by them, but You are just too hot.
17
Which brings us to fever.
18
For any microbe that wants to infect you, your body is a world they want to conquer.
19
Fever is defensive climate change, pushing an invader outside its ideal temperature range and making the world horrible.
20
It evolved at least 600 million years ago and is widespread.
21
Most animals increase their core temperature when they're sick.
22
Fish swim into warmer waters, Lizards bathe in the sun, bees heat up the air inside their hive.
23
But you, warm-blooded mammal, you have way more drastic options.
24
Let's make you sick and see what happens.
25
When your blood turns into larva.
26
You're invaded by bacteria and viruses at the same time.
27
The invasion is powerful and you need to slow it down as fast as possible.
28
Fever is part of your first line of defense, triggered by a diverse group of chemicals called pyrogens, the creators of heat.
29
They float away from the battlefield and pass right into your brain, where specialized receptors pick them up and crank up your internal thermostat.
30
First, you begin to shiver.
31
Your skeletal muscles contract really quickly, which generates a lot of heat in your core.
32
At the same time, usually the blood vessels near your surfaces contract and prevent heat from escaping through your skin.
33
Your skin cools down while your insides burn.
34
Fever is a systemic body-wide response and is a serious energy investment for your body.
35
You burn about 10% more calories to stay alive for every degree centigrade your body temperature rises.
36
Fever is also a strong order to lay down and rest to save energy and give your immune system time to fight.
37
Back to the battlefield.
38
When the bacteria entered your body, they tried to be stealthy, but now they've switched into high production mode.
39
Their goal is to multiply as fast as possible, which means they need a lot of resources and are highly stressed.
40
Imagine running a marathon while eating a succulent Chinese meal and giving birth.
41
The last thing bacteria need right now is more stress.
42
So your immune system tries to stress them out as much as possible by ordering inflammation, which floods the battlefield with fluids, attack proteins and soldiers.
43
Pretty stressful.
44
Fever is even more stress.
45
For the bacteria a moment ago, the temperature range was pleasant.
46
Now the world burns.
47
Heat can cause their organs to break and the membranes to rupture, damage their DNA and diminish protein production.
48
They are seriously suffering from the heat.
49
Why doesn't this affect your cells?
50
It does.
51
All of this is stressful for your cells too.
52
Virtually every system and organ of your body works worse during fever except one, your immune system.
53
Neutrophils are recruited faster, macrophages and dendritic cells are better at devouring enemies, killer cells kill better, and so on.
54
And fever animates your immune cells to gobble up the critical resources your enemies need, like iron, glucose and glutamine, turning the battlefield into a food desert.
55
The viruses that infected millions of cells are doing even worse because they are also very sensitive to heat.
56
For example, the rhinovirus that causes the common cold can only infect your respiratory tract
57
because it is significantly colder than the rest of your body, even without fever.
58
The heat is also really bad for the millions of cells that are infected by viruses at this point.
59
They are working super hard producing viruses, which is pretty stressful.
60
As the heat becomes too much to bear, the super stressed cells panic.
61
If their internal machinery is breaking and failing, they quickly produce billions of heat shock proteins, or HSPs, that start repairs, keeping them alive.
62
But this is a trap.
63
Even your healthy cells produce HSPs to deal with the heat, but if a cell makes too many of them, this means it's more stressed than it should be.
64
And if it's too stressed, something is wrong and it should be killed.
65
So your natural killer cells and killer T cells are activated
66
and attracted by HSPs and start killing infected cells and all the viruses inside them.
67
By trying to protect themselves, infected cells are calling out to be destroyed.
68
But if fever is such an effective weapon, why don't your enemies adapt to it?
69
How is it still viable in so many different animals after hundreds of millions of years?
70
A wild reason is that fever actually might outsmart evolution.
71
If your enemies survive fever long enough, natural selection changes them.
72
The individuals that are better suited to deal with heat reproduce more.
73
After a few days, they've adapted.
74
But this becomes a handicap because the next step is to infect new victims in new bodies.
75
And now, healthy humans are too cold for them.
76
Not impossible to infect, just harder.
77
And the heat-resistant microbes now compete with their cousins that like it colder and have an advantage infecting healthy hosts.
78
This creates an evolutionary dilemma without a perfect solution.
79
To circumvent this, serious pathogens like measles use hit-and-run tactics.
80
The measles virus is the most infectious right before your fever hits with full force.
81
It's brutally beaten back once your full immune response shows up.
82
But by then, the damage is done.
83
Fever is an effective part of the puzzle of your immune system, helping to attack and stress your enemies from as many angles as possible.
84
But if fever is so great, why do we stop it when we're sick?
85
Should you fight fever with medications?
86
We think it's normal to have magic pills,
87
but relatively harmless, over-the-counter pain medication like aspirin or ibuprofen only became cheap and widely available in the last century or so.
88
Going to a pharmacy to get something for your headache is extremely new in human history.
89
Pain feels bad, so we've gotten used to stopping it when we feel it.
90
If you're sick, you're supposed to feel a reasonable amount of pain so you lie down and save energy.
91
This is not a bug, but a feature of your immune system.
92
But pain and fever are closely connected, and over-the-counter pain medication like ibuprofen and paracetamol also work against fever.
93
Especially in children, fever is often suppressed by worried parents or doctors, sometimes because they think fever itself is the disease,
94
or they're worried that it can do long-term harm.
95
In general, it's fair to say that for temperatures below 40 degrees Celsius or 104 Fahrenheit, fever is not dangerous and doesn't need to be treated.
96
Of course, there are also patients that should not have fever, like pregnant women, seniors and seriously weakened patients.
97
For them, the extra stress may be dangerous.
98
Fever over 40 degrees Celsius is dangerous to anybody, because it's most likely caused by your internal heat monitor failing.
99
Things get more complicated in serious disease territory.
100
We also have evidence that for some diseases like influenza or chickenpox, anti-fever drugs do not help you to heal faster.
101
But we're also running into ethics problems here that make clinical trials difficult.
102
In one study, doctors gave strong anti-fever treatment to critical care patients, but had to stop after mortality shot up.
103
Overall, we have strong indications that more people may survive serious infectious diseases better with a fever.
104
And there is very little clinical evidence that stopping fever leads to better health outcomes.
105
But there are important exceptions like neurological injuries and stroke.
106
We definitely need a lot more research.
107
So, should you fight fever?
108
Well, speak to your doctor and don't listen to internet videos.
109
But this decision is really about payoffs.
110
If a fever is not dangerously high and you can bear it, you're supporting your defenses and may even get healthy a bit faster.
111
But if you feel really bad and are healthy in general, taking a pill against pain
112
and fever will make you feel better quicker at the cost of a slightly less effective immune defense.
113
However you decide, the next time you're burning up and feeling bad, you can rest easy in the knowledge that your enemies are having a much worse time than you.
114
It's thanks to doctors and researchers that we have these insights.
115
We're just doing our part by bringing them to you.
116
If you are also aiming to make a positive difference in the world, where should you start?
117
Today's sponsor, 80,000 Hours, can help you with that decision.
118
80,000 Hours is a non-profit career advice organization
119
that wants to help people find fulfilling careers that also do a lot of good in the world.
120
And their advice is free, without any hidden cost or fee later on.
121
Like us, they care a lot about making sure their work is based on the best available evidence and consultation with experts.
122
So they spent the last decade compiling
123
and conducting research into topics like how much impact can one person actually have
124
and what are the best ways to make a positive difference on important global issues.
125
Turns out following a well-known career path isn't your only option to achieve that goal.
126
In fact, there may be many paths
127
that make an even bigger difference in the world that you may not have even heard of.
128
The time you'll spend on your career is probably your biggest opportunity to have an impact.
129
If you want to make the most of it, join the newsletter now and get a free copy of their in-depth career guide sent to your inbox.
130
Just sign up at 80000hours.org slash in a nutshell.
131
Thank you.
📺 Même chaîne
C120
Your Skeleton Is Electric
IELTS PrepUniversity StudentsWorking Adults
C1113
Could Humans Evolve Flight?
IELTS PrepUniversity StudentsWorking Adults
B2133
Can Earth Run Out of Water?
IELTS PrepUniversity StudentsWorking Adults
B232
Your Brain Peaked at Birth
IELTS PrepUniversity StudentsWorking Adults
B232
Why Ebola Keeps Coming Back
IELTS PrepUniversity StudentsWorking Adults
B2555
What If You Never Slept?
IELTS PrepUniversity StudentsWorking Adults
C17
3 Reasons Why Nuclear Energy Is Terrible! 2/3
IELTS PrepUniversity StudentsWorking Adults
B28
Would You Upload Your Mind?
IELTS PrepUniversity StudentsWorking Adults
C11
Your Brain on Magic Mushrooms
IELTS PrepUniversity StudentsWorking Adults
B264
What the Flu Does to Your Body
IELTS PrepUniversity StudentsWorking Adults
C12
Is War Over? — A Paradox Explained
IELTS PrepTOEFL PrepUniversity Students
C15
How ADHD Medication Works
Daily ConversationUniversity StudentsWorking Adults
C11
The Most Complex Language in the World
IELTS PrepUniversity StudentsWorking Adults
B25
Let’s Steal a New Moon
IELTS PrepTOEFL PrepUniversity Students
C1758
How Stress Changes Your Brain
IELTS PrepTOEFL PrepUniversity Students
C13
What Happens AFTER Nuclear War?
IELTS PrepUniversity StudentsWorking Adults
B21
3 Reasons Why Nuclear Energy Is Awesome! 3/3
IELTS PrepUniversity StudentsWorking Adults
B252
Can We Stop the Extinction?
University StudentsWorking Adults
B26
YOU Own the Moon. And Mars. And Venus.
IELTS PrepTOEFL PrepUniversity Students
C1209
The True Cost of War
IELTS PrepTOEFL PrepUniversity Students
✨ Vidéo recommandée
C18
118 phrases
This Disease is Deadlier Than The Plague
IELTS PrepTOEFL PrepUniversity Students
C146
12 phrases
Why Do We Itch?
IELTS PrepTOEFL PrepUniversity Students
B25
227 phrases
When Heat Becomes "Unsurvivable": How Do We Adapt? | CNA Correspondent
IELTS PrepTOEFL PrepBusiness English
C16
108 phrases
Homeostasis - How Your Body Keeps its Balance - Physiology Series
IELTS PrepTOEFL PrepUniversity Students
C11
380 phrases
A man hiked in the woods. Every brain cell got cooked.
IELTS PrepTOEFL PrepUniversity Students
C12
530 phrases
Human Immortality 4K | Can Science Defeat Aging?
IELTS PrepTOEFL PrepUniversity Students
C17
159 phrases
Introduction to the immune system
IELTS PrepTOEFL PrepUniversity Students
C11
222 phrases
How Fire Made Us Human
IELTS PrepUniversity StudentsWorking Adults
C13
67 phrases
Why Don't Snakes Poison Themselves?
IELTS PrepTOEFL PrepUniversity Students
C11
270 phrases
The Most Misunderstood Concept in Physics
IELTS PrepTOEFL PrepUniversity Students
C13
31 phrases
4 Subject Link 6 C1
IELTS PrepTOEFL PrepUniversity Students
C14
131 phrases
The medicine myth | Denis Noble, Nessa Carey, Guy Brown
IELTS PrepTOEFL PrepUniversity Students
Vocabulaire et conseils d’expression pour cette leçon
Cette leçon d’expression orale de niveau C1 s’appuie sur la vidéo « Fever Feels Horrible, but is Actually Awesome! ». Les mots qui reviennent le plus souvent : fever, heat, cell, immune, temperature. Cette vidéo contient 131 phrases et 1794 mots à répéter en shadowing. La partie parlée dure 11:05. Le locuteur parle à un rythme naturel d’environ 162 mots par minute, proche d’une conversation courante. Seuls 81 % des mots font partie des 3 000 mots les plus courants en anglais, le vocabulaire est donc exigeant.
Vocabulaire clé de cette vidéo
Les 15 mots les plus avancés de la vidéo, avec leur prononciation et leur sens :
| Mot | Prononciation | Sens |
|---|---|---|
| infect verbe | /ɪnˈfɛkt/ | infecter |
| bacterium nom | /bækˈtɪəɹ.ɪəm/ | bactérie |
| stressful adjectif | /ˈstɹɛsfəl/ | stressant |
| battlefield nom | /ˈbætəlˌfiːld/ | champ de bataille |
| microbe nom | /ˈmaɪkɹoʊb/ | microbe |
| adapt verbe | /əˈdæpt/ | adapter |
| pill nom | /pɪl/ | pilule, comprimé |
| ibuprofen nom | /ˌaɪ.bju.ˈpɹoʊ.fən/ | ibuprofène |
| infectious adjectif | /ɪnˈfɛk.ʃəs/ | contagieux |
| machinery nom | /məˈʃiːnəɹi/ | machines, parc de machines |
| animate adjectif | /ˈæn.ə.mət/ | animé |
| aspirin nom | /ˈæs.pɹɪn/ | aspirine |
| circumvent verbe | /səːkəmˈvɛnt/ | contourner |
| compile verbe | /kəmˈpaɪl/ | compiler |
| dangerously adverbe | dangereusement |
Les verbes à particule que vous entendrez
| Mot | Prononciation | Sens |
|---|---|---|
| lie down verbe | s'étendre, se coucher | |
| turn out verbe | se finir, se terminer | |
| cool down verbe | /kuːl ˈdaʊn/ | se refroidir, refroidir |
| heat up verbe | chauffer | |
| show up verbe | apparaître, se montrer se pointer |
Des phrases à répéter
Des phrases courtes et complètes de la vidéo, à réutiliser dans la conversation de tous les jours :
- How does it make your immune defense stronger?
- Let's make you sick and see what happens.
- Why doesn't this affect your cells?
- Should you fight fever with medications?
La grammaire de cette vidéo
Les structures que le locuteur utilise le plus, avec les mots exacts de la vidéo :
| Structure | Dans la vidéo |
|---|---|
| Voix passive be + participe passé — l’accent est mis sur ce qui arrive, pas sur qui le fait | are infected · are recruited · should be killed |
| Present perfect have/has + participe passé — une action passée qui compte encore maintenant | they've switched · they've adapted · we've gotten |
| Propositions relatives who / which + proposition — une précision sur une personne ou une chose | possible, which means · viruses, which is |
Prononciation à surveiller
Le locuteur utilise 19 contractions et formes réduites, comme you're, we're, doesn't. Prononcez-les sous leur forme courte, telles que vous les entendez.
- Les sons « th »: pathogen /ˈpæθəd͡ʒn̩/, stealthy /ˈstɛlθi/, thermostat /ˈθɝməstæt/, thrive /θɹajv/, thermal /ˈθɜːməl/
- Les sons « sh » et « zh »: infectious /ɪnˈfɛk.ʃəs/, machinery /məˈʃiːnəɹi/, diminish /dɪˈmɪnɪʃ/, nutshell /ˈnʌt.ʃɛl/, shiver /ˈʃɪvɚ/
- Mots longs — placez bien l’accent: ibuprofen /ˌaɪ.bju.ˈpɹoʊ.fən/, machinery /məˈʃiːnəɹi/, paracetamol /ˌpɛɹ.əˈsiː.təˌmɔl/, influenza /ˌɪn.fluˈɛn.zə/, neurological /nɝəˈlɑd͡ʒɪkəl/
Les sons difficiles pour les francophones :
- /h/ — il se souffle, il n’est pas muet: hive /haɪv/, handicap /ˈhændikæp/, harmless /ˈhɑɹmləs/, headache /ˈhɛdeɪk/
- /tʃ/ et /dʒ/ — à ne pas adoucir en « ch » et « j »: macrophage /ˈmækɹɔʊː.feɪd͡ʒ/, pathogen /ˈpæθəd͡ʒn̩/, rupture /ˈɹʌpt͡ʃɚ/, neurological /nɝəˈlɑd͡ʒɪkəl/, niche /nɪt͡ʃ/
- /r/ anglais — langue recourbée, sans frotter la gorge: bacterium /bækˈtɪəɹ.ɪəm/, stressful /ˈstɹɛsfəl/, microbe /ˈmaɪkɹoʊb/, ibuprofen /ˌaɪ.bju.ˈpɹoʊ.fən/, suppress /səˈpɹɛs/
Comment s’entraîner avec cette vidéo
- Écoutez la vidéo en entier une fois sans parler et notez les mots que vous ne connaissez pas.
- Commencez à la vitesse 0,75×, répétez phrase par phrase, puis revenez à la vitesse normale quand cela devient facile.
- Enregistrez-vous et comparez avec l’original, en faisant attention à des mots comme infect, bacterium, stressful.
Qu'est-ce que la technique du Shadowing ?
Le Shadowing est une technique d'apprentissage des langues fondée sur la science, développée à l'origine pour la formation des interprètes professionnels. Le principe est simple mais puissant : vous écoutez de l'anglais natif et le répétez immédiatement à voix haute — comme une ombre suivant le locuteur avec un décalage de 1 à 2 secondes. Les recherches montrent une amélioration significative de la précision de la prononciation, de l'intonation, du rythme, des liaisons, de la compréhension orale et de la fluidité.