Xand van Tulleken:
Everyone knows exercise is good for you, right?
Chris van Tulleken:
What if I don't wanna do exercise?
Xand van Tulleken:
Jog!
Chris van Tulleken:
Drive.
Xand van Tulleken:
Stairs?
Chris van Tulleken:
Escalators.
Xand van Tulleken:
Get some exercise!
Chris van Tulleken:
Relax and check out the lovely view.
Xand van Tulleken:
[GASPS]
Chris van Tulleken:
Nice of you to join me, Xand!
Xand van Tulleken:
Well this is a lovely view!
Xand van Tulleken:
Everyone knows that exercise makes you fitter and healthier. But did you know that exercise could also help you think, or improve your mood?
Chris van Tulleken:
Well today we are going to investigate the effect of exercise on the most important organ of all. That's right, the organ that makes you you.
Xand van Tulleken:
My nose. I think it's regal appearance gives me an air of authority.
Chris van Tulleken:
Not your nose, Xand, your brain!
Xand van Tulleken:
What? Aah [SCREAMS]!
Chris van Tulleken:
Our plan to investigate the effect of exercise on our brains is very simple.
Xand van Tulleken:
Earlier today, we did a test to measure how smart we are when we relax.
Chris van Tulleken:
We'll do the same test again after some exercise. Will anything have changed?
Xand van Tulleken:
As identical twins, our bodies are very similar to each other. So we can compare how small changes affect us.
Chris van Tulleken:
So today, one of us is going to do the exercise.
Chris van Tulleken:
And one of us isn't. Right Xand, heads or tails?
Xand van Tulleken:
Tails.
Chris van Tulleken:
Tails it is!
Xand van Tulleken:
Yes!
Chris van Tulleken:
Now that means that today, you get to do all the exercise while I have to put my feet up and relax.
Xand van Tulleken:
The one who wins has to do all the work?
Chris van Tulleken:
That's right. And I'll see you at the gherkin.
Xand van Tulleken:
The Gherkin?
Chris van Tulleken:
Tall glass building over there, looks like a gherkin. There's your bike helmet, and hi-vis jacket!
Xand van Tulleken:
But Chris, it's miles away!
Chris van Tulleken:
And that's why I'm getting the tube!
Xand van Tulleken:
What?
Chris van Tulleken:
Now it may look like I'm cheating, but what I'm doing is super important, as I'm what scientists call the control.
Chris van Tulleken:
Now the job of the control is to remain the same throughout an experiment, so that any differences in our results at the end of the test can be put down to the variable.
Xand van Tulleken:
And today, that variable is me, the one doing the exercise!
Xand van Tulleken:
Already I'm breathing more deeply and my heart is beating faster. That's so that my lungs can get more oxygen into my blood, and my heart can pump that blood around my body. So this exercise is giving my circulatory system a really good workout.
Chris van Tulleken:
Talking of circulatory systems, I'm sitting inside a giant one right now.
Chris van Tulleken:
The London underground moves over a billion people a year around this vast city, and the map is world famous.
Chris van Tulleken:
Hidden tubes moving everything around, a lot like the circulatory system of your body. The tubes are thousands of tiny blood vessels, and instead of trains, there are trillions of red blood cells, carrying oxygen as passengers. And one organ that's hungry for oxygen is the brain. It makes up just two percent of the body's weight, but uses around 20 percent of the oxygen youbreathe. The brain uses oxygen to break down sugars and produce energy. Oxygen powers your thoughts.
Chris van Tulleken:
[SIGHS] I wonder how Xand and his circulatory system are getting on.
Xand van Tulleken:
It's not just more oxygen that gets to your brain when you exercise. Your body releases soothing chemicals and you actually start to feel happier. I do feel happier, I feel great, I feel happy!
Chris van Tulleken:
And I feel, being the control is harder than I thought.
Xand van Tulleken:
There's time for a quick scientific detour.
Xand van Tulleken:
Here at Barts Pathology Museum, there are artefacts from the earliest days of scientific investigation, and these are actual human brains, the most complex and mysterious organ in the human body.
Xand van Tulleken:
Now just like a supercomputer, your brain needs lots of power. So it's no wonder that it grabs as much oxygen as possible.
Xand van Tulleken:
Scientists have taken scans of the brain during exercise, that show increased levels of electrical activity.
Xand van Tulleken:
Our investigation today should show that rather than tiring you out, a little exercise actually wakes your brain up a bit.
Xand van Tulleken:
I said "wakes your brain up a bit!"
Chris van Tulleken:
What? Not doing anything often makes you feel sluggish and sleepy. This is my stop!
Xand van Tulleken:
At last, our goal, the skyscraper known as the Gherkin, 118 metres of glass and steel.
Chris van Tulleken:
Oh, there you are, what took you so long?
Xand van Tulleken:
That, Chris, is what you call controlled moderate exercise. There was no place for competition in an experiment.
Xand van Tulleken:
If the scientist theory is correct, my leisurely cycle should already have made me smarter and happier.
Chris van Tulleken:
While I should be pretty much the same as before.
Xand van Tulleken:
How did you do?
Chris van Tulleken:
Well, my memory span actually got a bit worse.
Xand van Tulleken:
Mine got better!
Chris van Tulleken:
My reaction time got slower by a couple of hundred milliseconds.
Xand van Tulleken:
Well mine's faster! This calls for a celebration, for me at least!
Chris van Tulleken:
Not so fast, Xand, because there's one more thing I want to check, and that is the effect of maximal effort. Really working up a sweat, in your case by running to the top of that! Now here are your trainers. I'm gonna get the lift because I'm of course the control!
Xand van Tulleken:
But, but Chris, that's massive! Chris?
Chris van Tulleken:
For this investigation, we really need to get the blood pumping around Xand's body and into his brain. 32 floors should do the trick.
Xand van Tulleken:
So my heart is really beating hard now. That means more blood and more oxygen to important organs like my muscles and of course my brain. My body has been storing sugar in the form of glycogen for this very moment. Now it's being released for extra energy and that's waking up my brain as well.
Xand van Tulleken:
Floor 29, I hope this is all worth it!
Recorded voice (lift):
32nd floor.
Chris van Tulleken:
Oh, my ears have just popped, I hope Xand releases how much I'm suffering for science!
Xand van Tulleken:
Yes!
Chris van Tulleken:
Well done, big brother. That was definitely maximal effort. Let's see how it affected your brain.
Xand van Tulleken:
[GASPS]
Chris van Tulleken (unsure):
If scientists are correct, the effect of exercise on your brain isn't just short-term. The extra oxygen could help brain cells grow in the parts of your brain that control words, memory and learning.
Chris van Tulleken:
Well Xand, the maximal effort results are in. And I haven't really changed because I haven't really done anything. But you, on the other hand.
Xand van Tulleken:
Well come on, don't keep me in suspense!
Chris van Tulleken:
Well, your memory has got a tiny bit worse than it was at the bottom of the stairs, but your reaction speed has got even quicker!
Xand van Tulleken:
Wow! So I am tired at the end of doing all that, and yet I've actually got better at something!
Chris van Tulleken:
Success! Our small-scale sample of two appears to show that exercise does indeed improve your brain.
Xand van Tulleken:
But to really investigate a theory, scientists have to perform an experiment hundreds, maybe thousands of times.
Chris van Tulleken:
And that's where you lot come in. Out there, and in there!
Xand van Tulleken:
Hello.
Chris van Tulleken:
We need you to do your very own controlled version of this investigation.
Xand van Tulleken:
So get investigating.
Chris van Tulleken:
Yeah, what are you waiting for? Get on with it.
Xand van Tulleken:
Go on, get investigating, come on!..What are you waiting for?