Практика Shadowing: How Caffeine Affects Exercise & Athletic Performance - Изучайте разговорный английский по видео
Создание урока...
1
Caffeine is one of the most widely used psychoactive substances in the world.
2
Now, most of the time we think of caffeine as a stimulant that could help us feel more alert or awake, or get us through the workday, if you will.
3
However, caffeine as a performance enhancer for exercise, sports, and athletics is getting more and more attention,
4
with people using energy drinks or pre -workout supplements that contain caffeine, with the hopes in that it could maybe improve endurance,
5
or improve weightlifting capabilities or even just improve performance in certain sports.
6
So in today's video we're gonna talk about if caffeine can actually improve exercise and athletic performance, how it could possibly do this,
7
and the amount that you would need to take in order to get some of these potential benefits.
8
It's going to be a stimulating one, so let's do this.
9
So let's start by answering the first big question.
10
Can caffeine improve exercise and athletic performance?
11
Now there have been countless studies done on this, a handful of which we'll include in the description below, but the overall answer is yes, caffeine can improve exercise and athletic performance.
12
And it seems that these benefits of caffeine can be applied to a wide range of different exercises.
13
For example, caffeine has been shown to improve exercise capacity at prolonged submaximal exercise,
14
things lasting longer than 90 minutes like a long run or a long bike ride, but it has also been shown to improve it at the mid -range or more of a little bit higher intensity,
15
something that you might only be able to do for like 20 to 60 minutes.
16
Not only that, it's been also shown to improve at the higher intensity, it's like that high intensity interval timeline of one to five minutes.
17
So that you can see caffeine
18
and these improvements can be applied to a wide range of cardiovascular dominant type exercise
19
that requires a lot of output from the heart and cardiovascular system.
20
Not only that, caffeine has also been shown to improve movement velocity during resistance training, so moving weights faster, and also has been shown to improve reaction time.
21
So you can see how these characteristics or improvements in those two characteristics could be applied or be beneficial to weight training,
22
or sports that require explosive movements like throwing or jumping, or maybe even a sport that might require improvement in reaction time,
23
like maybe you're a martial artist and you need to react to a ninja kick coming towards your head.
24
But how is caffeine doing this?
25
What is it doing inside of your body that is accounting for these potential performance benefits?
26
Well, we're going to take a look at two main mechanisms.
27
One is how caffeine is a stimulant of the central nervous system, and the central nervous system or CNS in anatomy just includes the brain and the spinal cord.
28
And then we'll also look at how caffeine could possibly affect muscle tissue.
29
So let's start with the central nervous system by zooming in to what we'd find in your brain.
30
Now to be fair, this is a very simplistic drawing of what you'd find in your brain.
31
Really I just drew one neuron or one nerve cell, but the reality is you'd find billions of these neurons throughout your brain and nervous system.
32
But we actually only need to take a look at one to understand how caffeine affects athletic performance.
33
So if we take a look at this extension from the neuron, this is called the axon.
34
And I've drawn some branches here and I've zoomed into one of those branches by drawing it up here.
35
It's called the axon terminal, just the end of the axon and there are multiple receptors or chemicals that you find throughout your brain and nervous system.
36
We're obviously gonna focus on the receptor that has to do with caffeine, and I've drawn this in as these little green Ys, and these green Ys represent the adenosine receptor.
37
Now the blue diamond is the actual adenosine molecule which will obviously bind to the adenosine receptor, like a lock and key analogy.
38
You need a very specific shaped key to fit into a very specific shaped lock in order to turn
39
or activate that lock.
40
Now, it's thought that adenosine will build up on the outside of your neurons as the day goes on.
41
And maybe you've heard of something called ATP, which stands for adenosine triphosphate.
42
ATP, or adenosine triphosphate, is the energy currency for your cells.
43
And your neurons actually burn through a lot of energy or ATP throughout the day. So again,
44
that adenosine starts to build up on the outside of the neurons and then can start binding to those adenosine receptors.
45
But what does that cause to have happen?
46
Well, when adenosine binds to the adenosine receptors, it suppresses the activity of your neurons.
47
So your neurons will fire less frequently, less intensely.
48
And to you, that feels like you might feel a little bit more tired or fatigued, less focused, less alert.
49
But we bring caffeine into the picture.
50
You ingest it in some way, it gets into your bloodstream.
51
And we've got this nice little blood vessel coming into the brain here with our little red caffeine molecules
52
and the caffeine will diffuse from the bloodstream and bind to one of those adenosine receptors.
53
It's close enough in shape to the original adenosine to bind, but not close enough to actually activate the receptor.
54
Maybe you've put a key into a lock that.. fits in there but not quite enough to actually turn the lock.
55
Think of caffeine as doing that as getting in that lock, getting in that receptor and blocking it, so then adenosine can actually get into those receptors.
56
So caffeine blocks the effects of adenosine and therefore has these opposing effects.
57
Instead of feeling tired, less alert, more fatigued, you get increased awareness,
58
increased alertness, you're more focused and you can definitely apply those characteristics to athletic performance
59
and performing better in certain sports to be more focused and more alert.
60
But it doesn't only just stimulate or increase awareness, caffeine also suppresses your perception of effort.
61
Meaning, you're exercising at a certain intensity, it will feel a little bit less of an effort
62
or you feel like you're putting less effort in than you would without caffeine.
63
Now, caffeine also suppresses your perception of pain to a certain degree.
64
And so if you also suppress pain to a certain degree, we've all had those moments when we've been exercising
65
or playing sports where it's uncomfortable or maybe even causing a little bit of pain.
66
So if caffeine can also suppress the pain a little bit, again, you're going to be able to push it a little bit further and therefore increase athletic performance. So hopefully
67
that gives you a good baseline understanding on how caffeine works
68
on the central nervous system to help you feel a little bit more focused and alert during sports and exercise, as well as helps to diminish that perception of effort and even pain and discomfort.
69
But how does caffeine affect your muscle tissue?
70
Well, there are studies that suggest that caffeine affects intramuscular calcium or the calcium inside of your muscles.
71
Now this is significant because calcium plays a huge role on how your muscles contract.
72
So let's quickly explain this and then apply it to caffeine.
73
If you take a look at this biceps, you can see that it's made up of multiple muscle fibers or muscle cells.
74
And if we zoomed into an individual muscle cell and into the myofibro, we would see that we have these little contractile subunits called sarcomeres.
75
And these sarcomeres are stacked end to end to end lengthwise throughout the muscle.
76
And this is about what the inside of a sarcomere would look like with our little whiteboard drawing here.
77
But this is where we can figure out how calcium works.
78
So taking a look at this picture of the sarcomere, you can see the thick filament in red.
79
And it kind of looks like a bundle of golf clubs
80
and each individual golf club would be a myosin molecule which is a contractile protein.
81
Now keep in mind I will mention some of the names here, but you actually don't have to memorize all these names to understand the concepts, I'm just going to mention the names for all the anatomy and physiology nerds out there.
82
But those myosin molecules
83
or the myosin heads where you'd actually hit the ball with the golf club want
84
so badly to bind to the thin filament which is in green
85
and it looks like little circular beads slightly twisted and each little bead or circle would be an actin molecule, another protein.
86
Now the problem here is that the myosin
87
and the actin can't bind together yet because that blue line that's wrapping around the thin filament or those actin molecules,
88
this is called the troponin tropomyosin complex or just TTC, it's blocking those binding sites.
89
And this is what a muscle actually looks like at the microscopic level in the resting state.
90
But, when the nerve sends the signal to the muscle to make it contract, what happens is is calcium within the muscle cell
91
and therefore within the sarcomere will actually be released and binds to the TTC,
92
that blue line, and shifts it slightly out of the way so now myosin and actin can bind and myosin ratchets.
93
And you get this ratcheting effect throughout all those sarcomeres and that in turn would shorten the muscle and create the contraction.
94
So, what does this calcium have to do with caffeine?
95
Well, there are studies that suggest that caffeine can enhance
96
and increase the amount of calcium released within the muscle cell and therefore within the sarcomere, thereby enhancing the contraction of the muscle.
97
And this could in part explain why they were seeing increases in contraction velocity during resistance training
98
when people were supplementing with caffeine.
99
And you could obviously apply this to being beneficial to weight training
100
and even sports or athletic events that require explosive movements like we mentioned earlier,
101
throwing, jumping, sprinting, etc. Caffeine can also affect the cardiac muscle tissue within the heart, causing that cardiac muscle to contract with more force during each beat
102
and therefore delivering more blood and oxygen to your skeletal muscles throughout your body.
103
And you can see if you get more blood and oxygen to working skeletal muscles, there could be multiple benefits or enhancements to different types of exercises and athletic events.
104
So how much caffeine do you need in order to get some of these benefits?
105
Well, it used to be thought
106
that you needed to take as much as 5 to 6 milligrams of caffeine per kilogram of body weight.
107
So I weighed in at about 184 pounds this morning and if we converted that to kilograms, that put me at just under 84 kilograms.
108
And so, if I went with a 6 milligrams of caffeine per kilogram of body weight, that'd be 6 times 84 and I'd be taking over 500 milligrams of caffeine.
109
Now, I don't know about you but
110
that amount of caffeine for me would be a lot and I'd likely just be bouncing off the walls.
111
Now, luckily, the more recent research has shown that you need much less than that to get some of these performance benefits,
112
almost half of that, like 2 to 3 milligrams of caffeine per kilogram of body weight.
113
So, if I went with a three, I'd be taking about 250 milligrams.
114
If I went with a lower end at two, I'd be taking in about 167 -ish milligrams of caffeine.
115
Now, most of the pre -workout supplements actually have about 200 milligrams of caffeine, which is a pretty good starting point.
116
But if you're one of those that's very caffeine naive, you don't take a lot of caffeine or maybe you're a little more sensitive to it,
117
you could start even lower at like a one to two milligram of caffeine per kilogram of body weight
118
and in these levels
119
that we're talking about two to three milligrams per kilogram of body weight are all well studied
120
and are relatively safe for most people but
121
if you continue to push the level eventually you're just going to get to creating side effects
122
and even potential safety concerns
123
because caffeine does not have what we'd call a dose response
124
relationship meaning the more you take the more performance benefits for exercise and athletics that you're going to get.
125
You're going to get to a point where that peaks out
126
and then you're just going to be dealing with side effects and again potential safety concerns.
127
And another thing we need to mention is timing.
128
When should you take the caffeine?
129
Caffeine is rapidly absorbed with about 99 % of it making it into the bloodstream within about 45 minutes of ingestion.
130
So you should take it about 30 to 60 minutes prior to exercise
131
or whatever sporting or athletic event you're trying to get some of these caffeine induced benefits from.
132
But what if If you're like me and you don't like to take caffeine every single day, maybe you don't drink a lot of coffee or other caffeinated beverages and personally,
133
I just don't like the idea of feeling beholden to something
134
that I could potentially develop a tolerance or dependence to and that can happen with caffeine.
135
Anyone who's been on caffeine consistently or for an extended period of time
136
and then they've cut it out cold turkey has likely noticed some of those withdrawal symptoms like headaches, irritability and other potential withdrawal symptoms.
137
Now, even though I don't like taking caffeine every day, it's still extremely hard for me to ignore some of these potential performance benefits.
138
So what do I do?
139
I tend to selectively pick and choose
140
when I'm going to take about 200 milligrams of caffeine and they're generally centered around more competitive days.
141
So on my regular training days, I don't usually take any caffeine.
142
But if I know I'm going to run say like an obstacle course race on a Saturday
143
or maybe have a really competitive game of basketball with my friends, I'll take some caffeine 30 to 60 minutes prior to those events.
144
And so for me, I'm taking it at most one to two times a week.
145
And that's more of just a personal choice for me to try to kind of avoid any
146
or reduce my risk of developing the dependence or tolerance to caffeine.
147
But that does not mean that you can't take caffeine every day.
148
Plenty of people do it.
149
Plenty of people take pre -workout almost every single day, drink their coffee every single day, and that's okay, and that works for them.
150
You just have to also realize that if you decide to cut back on it or cut a cold turkey, there is some of the risk to developing some of those potential withdrawal symptoms.
151
So hopefully that gave you a good understanding of how caffeine can help with exercise and athletic performance.
152
And I wanna leave you guys with an incredible learning opportunity.
153
And that's by saying thank you to the sponsor of today's video, Brilliant.
154
Brilliant .org is an amazing interactive online learning platform for STEM subjects.
155
It's one of the best ways to learn math, science, and computer science.
156
And trust me, I wouldn't say it's one of the best ways to learn math, science, and computer science if I didn't actually use Brilliant myself.
157
I have it on my phone.
158
I also use it on my laptop.
159
And some of my favorite courses are the courses on scientific thinking
160
because I love challenging my logic and learning how to apply new things that I've learned to actual real -world situations.
161
Another incredible thing about Brilliant is that they are constantly adding new lessons each and every month.
162
So no matter where you are in your educational journey, whether you're in junior high, high school, college, or just want to be a lifelong learner, Brilliant will definitely have lessons that are applicable to you.
163
So if you want to become a little bit more brilliant, go to brilliant .org slash IHA to start your free 30 -day trial.
164
Plus, the first 200 people will get 20 % off their annual subscription.
165
We'll also include that link and the info in the description below.
166
And I do want to mention that we do have another caffeine video
167
that we've done previously
168
that goes into a little bit more of the interactions in the central nervous system
169
and talks a little bit more about the potential side effects.
170
So, we'll link that to this video.
171
And I also want to say thank you all so much for your support and watching all of our crazy
172
anatomical and physiological videos.
173
We really appreciate it and we couldn't do this without all of you.
174
So, if you want to like, we definitely appreciate that.
175
If you're not subscribed and you want to, go ahead
176
if you feel the need and of course leave some comments below and we'll see you next time
📺 Тот же канал
✨ Рекомендуемое видео
C1130
17 предложений
How exercise benefits your body
Daily ConversationUniversity StudentsWorking Adults
C11
107 предложений
How to Quickly Improve Focus - Andrew Huberman
Business EnglishUniversity StudentsWorking Adults
C13
177 предложений
How to Create a Strength & Conditioning Program for Athletes | Programming for Athletic Performance
Business EnglishUniversity StudentsWorking Adults
C15
64 предложений
PhD Gives His Take on Creatine for Longevity
Business EnglishUniversity StudentsWorking Adults
C13
144 предложений
This Exercise Changes How Women Store Belly Fat
Business EnglishUniversity StudentsWorking Adults
C11
145 предложений
13k
Business EnglishUniversity StudentsWorking Adults
B21
297 предложений
This Will Change How You Store Coffee
Business EnglishDaily ConversationUniversity Students
C150 предложений
The Science of Stress: How Does Stress Affect Our Brains and Bodies?
Business EnglishUniversity StudentsWorking Adults
B22
112 предложений
How F1 drivers survive their own cars
Business EnglishUniversity StudentsWorking Adults
C120
38 предложений
Tools to Set Your Cortisol Rhythm
Business EnglishUniversity StudentsWorking Adults
C16
384 предложений
Dr. Andy Galpin: Does Cardio Ruin Muscle Growth?.
Business EnglishUniversity StudentsWorking Adults
C13
130 предложений
This Is What Happens When You Rely on Stimulants - Andrew Huberman
Business EnglishUniversity StudentsWorking Adults
О этом уроке
В этом уроке вы узнаете, как кофеин влияет на физическую активность и спортивные результаты, а также потренируете разговорный английский с помощью аудиоматериала. Вы научитесь понимать научные термины, связанные с биологией и спортом, и улучшите навыки воспроизведения речи — это идеально для тех, кто хочет улучшить произношение английского и попрактиковаться в shadowing.
Ключевой вокабуляр и фразы
- Psychoactive substance — психоактивное вещество
- Performance enhancer — препарат для улучшения результативности
- Endurance — выносливость
- Resistance training — силовые тренировки
- Adenosine receptor — аденозиновый рецептор
- Central nervous system (CNS) — центральная нервная система
Советы по практике
Видео имеет умеренный темп и четкую речь, что делает его отличным для shadowing. Начните с прослушивания коротких фрагментов (5-10 секунд) и повторяйте их сразу после записи, обращая внимание на интонацию и ударения. Используйте shadowing site или приложения для отработки — они помогут синхронизировать ваше произношение с оригиналом. Для сложных терминов (например, adenosine triphosphate) разбейте их на слоги и повторяйте несколько раз. Памятите: shadowing — это не только повторение, но и ощущение ритма речи. Постепенно увеличивайте длительность фрагментов, и вы заметите, как ваше произношение становится более естественным. И не забывайте: shadowspeak (или shadow speech) — это эффективный способ улучшить как понимание, так и речь на английском!
Грамматика в этом видео
Конструкции, которые говорящий использует чаще всего, с точными словами из видео:
| Конструкция | В видео |
|---|---|
| Условные предложения if + предложение, will/would + глагол — условие и его результат | if I went with a three, I'd be |
| Present Perfect have/has + причастие прошедшего времени — прошлое действие, важное сейчас | have been · has been shown · has also been shown |
| Пассивный залог be + причастие прошедшего времени — важно, что происходит, а не кто это делает | can be applied · has been shown · been shown |
| Придаточные определительные who / which + предложение — уточнение о человеке или предмете | molecule which will · molecule which is · filament which is |
Что такое техника Shadowing?
Shadowing — это научно обоснованная техника изучения языка, изначально разработанная для подготовки профессиональных переводчиков и популяризированная полиглотом доктором Александром Аргуэльесом. Метод прост, но эффективен: вы слушаете аудио на английском от носителей языка и немедленно повторяете вслух — как тень, следующая за говорящим с задержкой в 1–2 секунды. В отличие от пассивного прослушивания или грамматических упражнений, Shadowing заставляет мозг и мышцы рта одновременно обрабатывать и воспроизводить реальные речевые паттерны. Исследования показывают, что это значительно улучшает точность произношения, интонацию, ритм, связную речь, понимание на слух и беглость речи — что делает его одним из самых эффективных методов для подготовки к IELTS Speaking и реального общения на английском.