Getting Fit The Truth About...

I'm medical journalist Dr Michael Mosley.

It's that time of year when, like most of us,

I'm already struggling with my New Year's resolution

to become much more active.

Ooh! Now, I know I should do more regular exercise

but the honest truth is, I have neither the time

nor the inclination.

What I want is the absolute maximum gain for the minimum pain.

The good news is that new science is giving us the best ways to keep fit,

without taking up too much time.

More research is going into exercise than ever before and I'm delighted,

because what the latest science is showing us

is the most effective ways to get fit and healthy

with the minimum sweat.

So I'm teaming up with the scientists...

Off you go.

..who are turning what we know about fitness on its head.

That's excellent.

Together, we'll show you a far more effective way to walk yourself fit

than 10,000 steps...

-Going to follow me?

-Yes!

-Here we go. Right.

A little bit faster.

..how two minutes of intense exercise a week

may be all you need...

That's quite an easy way to get back into fitness.

..the latest research that will help you

actually stick to your fitness plans...

If you're relying on willpower for you to exercise,

it will probably fail.

..and the activity that can make you instantly cleverer.

It's so amazing to see the results, because I just think,

"I can shake, shake, shake, but actually to know, wow, I'm getting smarter..."

Whether you want to get fit, look good, lose weight,

gain strength or be healthier,

we're going to use the latest research to find

the most effective ways for you.

This is The Truth About Getting Fit.

We don't all love the gym.

In fact, 20 million Brits are classed as physically inactive.

But, if you are unfit, scientific studies show

you'll make the biggest health gains from doing even a little exercise.

So, what shape are you in right now?

How can you tell how fit you are at the moment?

Well, I'm going to show you a couple of simple tests you can do at home,

without having to use any fancy equipment.

Very good! Faster!

These are tests you can do right now in your house

and they will give you a quick, but reasonably accurate,

measure of your current fitness.

Helping me is Professor Lorna Paul,

a health scientist at Glasgow Caledonian University.

I like the idea that if you can't be bothered to go to the gym,

you bring the gym to your house.

Yeah. And, indeed, that's what we've done. What we are going to do today

is two tests that everybody can do in their own homes.

The first test is how long it takes you to stand up and sit down

from a chair ten times.

All you need is a hard chair and a way of timing yourself.

This test assesses one of the key aspects of fitness, our strength.

It's an important test,

because it's testing our big muscles in the lower limbs,

so our quadriceps at the front, and our gluteals at the back.

-These big muscles.

-Biggest muscles in your body!

These muscles start to weaken if we don't use them,

so it's the use it or lose it.

It's the time it takes that gives you your score.

That's 15. Well done. 17. Well done.

The faster, the better.

-How are we doing?

-Eight seconds.

OK! Good!

This test is used around the world

as a measure of how fit you are for your age.

Men under 35 should be able to do

ten chair stands

in ten seconds or less.

For women, it's 12 seconds.

If you're under 55,

men should do it in 13 seconds.

Women in 15 seconds.

And men over 55 should take

less than 18 seconds.

19 seconds if you are a woman.

It's harder than it looks.

-Yeah.

-Nine, ten.

Now it's time for test number two.

So, although this is clearly a bit of gym kit,

presumably you can just use the steps at home.

Yes, so if you've got stairs in your house

or you've got a front doorstep, just use the step you've got at home.

This is a test of aerobic fitness -

how strong your heart and lungs really are.

We're going to get you to step up and down on the step

for three minutes.

But we're going to set the pace, and we want you to keep to the pace.

It's up, up, down, down.

-OK.

-Up, up, down, down.

The key thing we're looking at is heart rate.

The lower your heart rate, the fitter you are.

If you're less fit, then your heart rate is going to have to go up more.

Yeah, your heart is going to have to pump harder to get that oxygen to

your tissues. So that's why heart rate

is a good indicator of your fitness.

Three minutes of steps later, it's time to take my pulse

and work out my beats per minute.

If you can't find it, think about where your index finger is,

and just come straight down.

If people find that hard, that might be a bit easier.

I reckon my pulse is about 96 at the moment.

For a man of your age, we'd certainly be looking

for a pulse under 115, so that's great.

That's a good measure of fitness.

What should your heart rate be?

If you're under 35 and male,

it should be

under 105 beats per minute.

For a woman, 110.

If you're a man under 55,

less than 110.

115 for women.

Over 55 and male, 115.

Female, 120.

So, those are a couple of tests you can do at home

to measure how fit you are at the moment.

But what should you do if you actually want to get fitter?

Well, keep watching.

One obvious way for most of us to get fitter is walking.

But how much do you really need to do to make a difference?

There is one number everyone bangs on about - 10,000 steps a day.

These days, you see a lot of people wandering around,

wearing something like this.

It's an activity monitor. And, amongst other things,

it keeps track of the number of steps you take.

10,000 steps a day is the goal.

10,000 steps to stay young and healthy for ever!

It's become a huge health craze -

13 million Brits now tracking their steps.

But where does that magic number come from?

In the run-up to the Tokyo Olympics in 1964,

a company came up with a device they called a Manpo Meter.

That literally means a 10,000 step meter.

So that magical figure didn't come as a result of

rigorous scientific studies, but was actually the product

of a clever marketing campaign.

It was clearly a great marketing slogan,

but is 10,000 steps really worth doing?

I've come to a factory in Sheffield,

where six employees have agreed to help me put it to the test.

Hi, all. Hello.

Thank you very much for agreeing to take part in this.

They all have different reasons for wanting to get fitter.

I'm very aware that I'm not as fit as I used to be

and I've put a lot of weight on.

My only hobby at the moment is knitting.

I've got a little six-year-old girl that runs about like a dafty

and I can't catch her up.

We're going to put the fabled 10,000 steps

up against a much shorter walking target.

Running the experiment is Professor Rob Copeland,

from Sheffield Hallam University.

So, you're going to test 10,000 steps against something

which may be more doable and more practical

and also, perhaps, more effective?

That's what we're really interested in,

exploring this concept of 10,000 steps -

is that really the best thing to aim for?

Or is there something that perhaps you could fit into your life

that might give you the same bang for your buck, if you like?

Fantastic. I'm in, then.

Rob is splitting our six volunteers into two groups.

Today, Dave, Darren and Gillian

will, a little reluctantly, be attempting to hit

the 10,000 step target.

That's around five miles.

All I want you to do is to incorporate 10,000 steps

into your normal day. Simple as that.

Meanwhile, Nathan, Gary and Judy

will be trying something Rob calls Active Ten.

What I'd like you to do today

is try to incorporate three ten minutes of brisk walking

into your normal day.

-We'll do it together.

-We'll do it together.

-And I'll race you.

-Walking buddies.

-Yes.

That's a good idea. I like that. It's a good idea.

Three sessions of an active ten minutes of brisk walking

adds up to a total of around one and a half miles, more like 3,000 steps.

Rob wants to compare the health effects

of these different approaches.

Everyone is given a monitor to track their activity.

And Rob is particularly interested in how much

they increase their heart rate.

Everyone goes back to work, with their new targets.

The 10,000 step group have quite a challenge on their hands.

To get 10,000 steps, today, one of the things I've been doing

is parking my car further away from the factory.

In an attempt to get my steps up,

I'm going to load the dishwasher item by item.

Fitting five miles of walking into a busy day can take some ingenuity.

For the Active Ten group, the aim is to get their pace up,

so they're working their heart and lungs.

This should get them a bit out of breath.

They can still talk, but not sing.

-You follow me?

-Yes.

-Here we go!

I'm joining them for their first brisk outing.

-ALL:

-# It's a long way to Tipperary... #

We're not going fast enough.

Shouldn't be able to sing!

One ten-minute walk down, two to go.

The next morning, everyone is back at the factory

to hand in their activity trackers.

So, how easy was it for the volunteers to reach their targets?

First, the 10,000 steps group.

Hi, gang. Good to see you again, looking lean and mean.

Gillian, Dave and Darren, two of you managed to achieve

your target of 10,000 steps, so well done.

Darren, you actually managed to do 11,000, so that was fantastic.

Dave, you were slightly below that - you managed just over 5,000 steps.

-Slightly below.

-Slightly below.

-Did you find it hard to hit that target?

-Yeah.

It took more time up from my day than I thought it was going to.

Dave, what do you think? You're shaking your head.

Yeah, no, I found it really difficult. I'm office-based.

I do, like, 2,000 normally, and I found it really hard work.

And what about the Active Ten group?

Nathan, Judy, and Gary, you all managed to fit into your daily life

these three ten-minute bouts of brisk walking,

so that's absolutely fantastic.

Well done for that. Really good.

So, how did you find doing those bursts of ten minutes?

Quite easy, actually.

Me and Nathan chose to do it together on two occasions,

which made it a bit more interesting as well.

And who was the driving force?

-Me.

-Yeah, definitely, definitely.

-Yeah.

10,000 steps was harder to achieve,

but which of our activities was better for health?

The Active Ten group actually moved for 30% more

in the moderate to vigorous physical activity intensity,

even though you moved for less time.

And that's where you start to get the greatest health benefits.

The recommended amount of exercise

is 150 minutes a week of moderate intensity physical activity.

This means getting out of breath and increasing heart rate.

So even though the Active Ten group spent less time moving,

they did more worthwhile moderate exercise.

What we wanted you to do, actually,

was to get your heart beating faster.

There's lots of evidence to suggest that you can lower your risk of

diabetes, cardiovascular disease, some cancers, even up to 20%,

if you can increase your physical activity.

You going to join the club, Dave?

It's not a very good looking club, but I'll...

-That's why we need you, Dave.

-Raise the average age.

That's why we need you.

So, three short brisk walks were easier to fit in the day

and better for health.

I thought that was really interesting

and I found it very encouraging,

because I really don't like doing 10,000 steps,

so the fact that you can get similar, perhaps greater, benefits

from a few brisk walks a day is enormously encouraging.

To start doing some Active Tens in your day,

you can download this free Public Health England app

to see how much brisk walking you're doing,

and how to do more.

If even 30 minutes of walking a day sounds a little too much,

then don't despair. It's possible to get significantly fitter

in far, far, less time.

There's a form of exercise which, it is claimed,

can give you the benefit of a long workout in a fraction of the time.

It's called Hiit - high-intensity interval training.

It's said that just two minutes a week can transform your body.

So, how much benefit can you really get from just two minutes a week?

To find out, we're doing an experiment

that has never been done before.

We're installing an exercise bike in this London office.

And six busy office workers will be putting it to the test.

Hi, all. Hello.

Thank you for volunteering.

Do you think it's going to work?

I really hope it will because, if it does,

then that's quite an easy way to get back into fitness.

Personally, I don't think it's going to work.

I'm more used to doing an hour, hour and a half,

of really intense exercise,

and feeling like I've had a proper workout.

Dr Niels Vollaard is an exercise scientist and Hiit expert.

First, he tests everyone's aerobic fitness,

by measuring how efficiently their body uses oxygen.

He will test them again in five weeks' time,

to see if they've improved.

Now it's time for their first session of high-intensity training.

They'll cycle as hard as they can, in just two bursts of 20 seconds.

Not as bad as I thought it was going to be, actually.

Yeah, it's pretty good.

It was harder than I expected.

I'd be delighted if it works.

They have to do 40 seconds of high-intensity sprinting,

three times a week.

That means two minutes a week in total, plus a warm-up

and cool-down each session.

Niels's research has shown that one of the main ways Hiit seems to work

is by triggering changes deep inside the muscles.

He can detect these changes using an ultrasound on Igor,

one of our volunteers.

So, what are you hoping to do here?

So, we're going to measure Igor's muscle glycogen,

or muscle sugar stores, here, before and after exercise.

In this image of Igor's muscle, the dark areas are glycogen,

a type of sugar that we store in our muscles.

Igor hasn't done any exercise today, so the muscles' sugar stores,

at the moment, are full. So, 100%.

Niels will measure his sugar store again after a Hiit sprint.

So, are you ready to go?

-Yep.

-OK, right. Good luck.

As Igor sprints, the sugar stored in his muscles is released,

broken down and used to power the exercise.

After the sprint, Niels measures the amount of sugar

that's left in Igor's muscle.

You looked as though you were going flat out.

You are really going for it, there?

It's definitely my max.

There are now fewer dark areas,

which means his glycogen stores have fallen.

They can calculate exactly by how much.

We have a result. He has a depletion

of 24% on average for his whole muscle.

OK, 24% of the sugar has been,

sort of, bashed up, smashed up and removed.

The body responds to this stress

by trying to make itself more resilient. It stimulates genes

which improve the function of the whole cardiovascular system.

And so it's also affecting the heart and all sorts of other things?

Yeah. The adaptations will affect the whole body,

even though they start off in the muscle.

-How are you feeling? Recovered?

-Yeah, I've recovered.

-A little bit.

-Another five goes?

No. No way.

All exercise releases some glycogen from our muscles,

but Hiit does it faster and more effectively.

To achieve the same results with other types of exercise,

you'd have to run for 45 minutes.

But does it actually make you any fitter?

Five weeks later, Niels is back to find out.

He's retesting the fitness of our office workers

to see whether this novel exercise regime

really has made any difference.

Yeah, we've analysed the results and I'm very pleased to say

that all of you improved.

Charlie, you were our star performer -

-14% increase in your fitness levels.

-Wow!

As a group, the improvement that we saw in your fitness levels

was on average 11%, which is an excellent improvement.

-Are you surprised?

-I'm very surprised, yeah.

-Definitely.

-I did run up the escalators today, and I did feel...

I didn't feel as out of breath as I would normally have felt.

An 11% increase in aerobic fitness is really impressive

and, if they keep it up, has significant health benefits.

You might think, "Oh, well, 11%, that's so-so."

That's actually really good.

We can compare that to risk of disease,

risk of getting heart disease, for example.

Your risk of getting heart disease over a certain amount of time

has been reduced, on average, by about 20%.

Do you think that, having heard the numbers,

you will be tempted now to keep going?

-Yeah.

-Absolutely.

-Definitely.

-You're all going for it, are you? OK, yeah.

In this office, it looks like the bike is here to stay.

Hiit, high-intensity training, isn't for everyone.

If you prefer going for a long run

or a vigorous game of football, great.

But if you're looking for something

which gives you the maximum health benefits

in the minimum possible time, then Hiit is it.

Hiit is clearly an incredibly efficient way

to get the most out of exercise,

but what if you don't have access to a Hiit bike?

Until very recently, almost all the studies which have looked at

the benefits of Hiit have been done on specialised bicycles.

But there is really new research which has shown it's possible

to get all those lovely benefits of Hiit without a bicycle -

in fact, without even leaving your home.

-Hi, Beth.

-Hi.

-Come in.

Dr Beth Phillips is an assistant professor at Nottingham University.

She's going to show me the short programme of intense exercise

that she has developed for you at home.

What do I do?

OK, so, this Hiit protocol is based around five minutes of hard work.

First, it's some gentle jogging to warm up.

Feels slightly bonkers doing this inside, but still, yeah...

The first exercise that we're going to go into is your star jumps,

OK? So, you're going to do a minute, hard and as fast as you can,

-so when you're ready...

-I'm ready.

-Off you go.

-OK.

Two, three, four...

Well done. That's great.

19, 20...

-Try and keep the pace.

-21, 22...

-And halfway.

-Halfway?

BETH CHUCKLES 32, 33...

I have to do as many as I possibly can in one minute.

And three, two, one, and recover.

So, that was about 57.

After a brief recovery, it's exercise two -

one minute of squats.

Make sure those knees don't go over your toes.

That's it. Weight on the heels.

-Well done.

-15, 16...

Nearly there. Last five seconds.

43...

Three, two, one, and recover.

Oh, feel them thighs. 46.

Now, exercise three - static sprinting.

Usain Bolt. That's it - keep it going, keep it going. Really good.

Well done. Keep going, come on.

That's it. Great stuff. Well done.

Really good. Come on, keep that pace, keep that pace.

That's it. Really, really well done.

20 seconds left. Three, two, one, and recover.

That was knackering!

Ha!

Certainly feel it.

Now I do the squats and star jumps again to finish.

That's it. Don't slow at the end. Keep it going.

Three, two, one, and recover.

Well done. Great work.

End of. How did you find it?

It was actually more intense than I was expecting it to be.

-And no equipment.

-No equipment at all.

In Beth's research, people who did five minutes

of these living-room exercises three times a week

made the same impressive gains in fitness as those who used a bike

in the lab. But it's worth getting a checkup before you start doing

high-intensity exercise, especially if you've been

inactive for a long time.

Try and get your knees up,

try and get the thighs parallel to the floor.

We've started by looking at the best ways

to improve your aerobic fitness - your heart and lungs.

But now I want to look at what the latest science says

is the best way to get stronger.

Strength training is a hugely important part of getting fit,

and it's often neglected.

There is, however, a trend, particularly amongst young women,

to building muscle under the slogan "strong over skinny".

These hard-won abs and toned biceps are the results of hours

pumping iron down the gym. But I'm hoping there might be an easier way.

So, what's the best way to build muscle?

Researchers from Glasgow University

are about to start an intriguing study to find out.

Dr Stuart Gray and his colleague Danai Stefanaki

want to test whether it's best to lift heavy weights

or if you'll get just as good results from lifting light weights.

They've got five female recruits

who currently don't do any strength training.

Do you think that strength exercises are more typically a male thing?

Do you perceive it as that?

I think, from my experience, certainly sometimes the gym I go to,

the weights area is full of men.

I think things are changing, though.

Young girls are much more inclined to go for strength now as opposed to

skinny, so they're wanting muscles and six-packs and things and putting

them up on Instagram rather than trying to look like Kate Moss.

To compare the effects of light and heavy weights,

they're going to use an unusual training method.

With one arm, our volunteers will lift a heavy weight

and with the other, a light weight.

And the same with the legs - heavy on one side, light on the other.

So is there a risk we'll end up

with one huge bicep and one not-so-huge bicep?

I wouldn't like to prejudge. We shall wait and see

what the result shows and we'll hopefully find out at the end.

There's just one important rule.

Both arms, regardless of the weight,

have to go until you can't lift any more.

Stuart measures how strong they are at the start by asking them

to lift the heaviest weight they can.

Up, up, up, up.

He'll measure how much stronger they are at the end.

Now training can begin.

They'll do two sessions a week for six weeks.

My first training session was good. It was pretty tiring.

I'm not really used to doing weights at all.

I can feel it already,

so I think tomorrow it's going to be even worse.

I felt really strange.

Obviously, the heavy one feels really strong on your arm,

whereas the light one feels like you're almost repeating nothing.

I'm feeling worked out and I've only been here a few minutes.

Strength training is important for our mobility and our health.

If we don't do it, there's a natural muscle wastage as we get older.

Normally about the age of 35, people will start to lose muscle -

roughly about 1% of your muscle mass every year.

You probably won't notice it until you kind of cross a threshold

where you lose the ability to carry out things,

tasks you could normally do, like climbing up the stairs,

getting off a chair and these kind of things.

The good news is, this loss of muscle mass can be prevented -

at any age.

So, these are MRI images which are looking down

into somebody's thigh from the top. You can see the kind of bone here.

A cross-section through the thigh?

Yeah, and then you've got the muscle tissue

and then you've got the fat just under the skin, round the edge.

So this is a 65-year-old who is relatively sedentary,

doesn't do a lot of physical activity at all,

and this is a 65-year-old who has throughout their life

done a lot of physical activity.

As well as maintaining mobility,

there are other important benefits to having bigger, stronger muscles.

They can reduce our risk of type-two diabetes.

Muscle is the main place where sugar goes when you eat a meal,

so this muscle here is going to be able to take a lot more sugar

than this muscle here, because of the size and quality of the muscle,

and if the sugar doesn't come out of the blood

and hangs about in the blood,

that's going to increase your risk of diabetes.

Right, so it's like a giant sponge in a way,

sucking the sugar out of your system and reducing the amount that is

circulating in a rather unhelpful way around the rest of you?

Our volunteers are hard at it with their training programme.

So, I've woken up this morning, my legs feel OK, my right arm feels OK,

but my left arm, I can definitely feel that I've put it to work.

Well, guys, do you think I'm more muscly?

I'm finding that the day after, the lighter side,

my lighter leg is really...

Especially the leg is really killing me.

After six weeks of commitment...

Oh!

..hard work...

..and determination...

..everyone has been retested to see how much stronger

their arms and legs are at the end.

So which has made more of a difference to their strength -

the heavy or the lighter weights?

Show of hands -

who thinks the heavy weight will produce the biggest result?

OK, that's two of you. Who thinks the light weight?

OK, one of you, and who's going for both? OK, two of you.

So, did it make any difference whether they were doing

the heavy weights or the light weights?

The short answer...is "no".

THEY CHEER

I knew it!

OK, so, two of you voted for no difference - exactly.

No gloating. Come on.

Regardless of weight, arms increased by 18%, 19%

and the legs by about 25%, but the weight made no difference at all.

An increase in strength of 25% in just six weeks is impressive.

And the volunteers haven't ended up lopsided.

They've got stronger by the same amount in both arms and both legs.

But which did they prefer?

The heavy or the light weights?

Who will actually want to continue with the heavy weights?

So, all of you.

All of you preferred the heavy weights to the light weights?

Interesting. Because I would have thought, I must admit,

light weights sound easier, but it wasn't?

No, I don't think light weights are easier.

I think it burns more at the time, so, yeah,

-I definitely don't think it's easier.

-And it took longer?

And it takes longer.

This is a surprise result.

We found that light weights are just as effective as heavy.

But all of the volunteers preferred the heavy weights,

because it didn't take as long.

I've never, ever been tempted to do weights before.

But I must admit, as a result of seeing what happened in this study,

I am going to take it up. And, like our volunteers,

I am tempted to use the kind of heavier weights,

because it's over and done with really fast.

Although you can, of course, do the lighter things but, in that case,

it's going to take you longer before you reach the point of exhaustion.

But the great thing is, you only need to do this twice a week.

To build muscle, you don't have to use weights.

You can use your own body weight

with exercises like squats and press ups.

Aim for twice a week, and keep going until you're tired.

So far, we've seen how the latest science is pointing us

towards quicker, more effective ways to improve

our aerobic fitness and our strength.

Heavy weights came out on top as the fast favourite to build muscle.

And whether it's brisk walks or short, sharp bursts of Hiit,

intensity is best.

The problem many of us face is how to make our good intentions last.

We waste nearly £600 million a year on unused gym memberships.

So what's the secret to sticking to our fitness plans?

Like a lot of people, I have these moments when I think,

"Ooh, I must get in shape,"

and so I start doing loads of exercise, and then I injure myself

or it gets cold and dark outside or perhaps I just get busy at work,

I give up, and then I find it incredibly difficult

to get motivated again.

So what is the secret behind discovering an exercise regime

that you will stick to? Is it simply a matter of willpower

or is it something else?

Willpower is all about determination,

making yourself do something that's not easy.

Studying it is exercise psychologist Dr Ian Taylor

at the University of Loughborough.

So, Ian, a lot of people sign up to places like this,

they pay their money, they come for a few weeks, and then they give up.

-Now, why is that?

-People are mostly motivated by willpower.

And it's a not-very-good motivation at all.

It's a very fragile type of motivation.

Hopefully, I'm going to demonstrate this to you in an experiment,

exactly how fragile it is.

Ian has invited ten volunteers to the University.

They've been told they are here to take part in a study

about exercise techniques.

But they don't know it's really a psychology experiment,

or that it has anything to do with willpower.

Who here has ever joined a gym?

-Me.

-All of you? OK.

I did try for about three weeks, but I only managed to get there twice.

I made about two months,

and continued paying the membership for about another six months.

We're going to look at what affects willpower,

and how big a part it really plays in how much exercise you do.

So, if we can have Sally, Sam, Brett, David and Alex on this side.

After being split into two groups,

each volunteer does a timed wall sit,

using their thigh muscles to balance against a wall,

which they'll repeat after their willpower has been tested.

Each group has their own experiment room -

identical, except one will feature some freshly warmed,

delicious smelling, tasty treats.

A volunteer from each group had been brought into their room

for stage one of the experiment.

They can't see us but we can see them.

What's going on in here?

So we've got a participant at the minute,

filling out some questionnaires, and they're completely bogus.

They're nothing to do with the experiment.

But what we've got on the table, as you can see, is some cookies.

Don't worry about the cookies -

they're for something we're doing later.

We've also wafted the smell of cookies.

Now, we've told the participants not to eat for a couple of hours

before the experiment, so they'll probably be hungry.

So the idea is that while they finish out those questionnaires,

they'll be tempted by the cookie smell

and they'll have to resist that temptation.

They'll be using willpower at the moment.

I mean, just standing here, I'm tempted. I can't smell them,

I can see them, I like cookies, I'm hungry,

-I want to go in there, grab one. I'm not going to.

-Exactly, exactly!

In the other room, their willpower won't be tested

before they're asked to exercise.

OK, same sort of room, no cookies.

Got a couple of questionnaires for you to fill out.

This is the room where they're doing exactly the same thing.

The only difference is, they can't smell cookies,

they can't see cookies.

So they're not being tempted,

they're not having to use willpower to resist the cookies.

After five minutes of form filling and some cookie smelling,

the volunteers repeat the wall sit.

So will having to use willpower to resist the cookies

affect how long they can do the exercise?

The hypothesis is that,

because they have not used any willpower to resist cookies,

they should be more willing to use willpower in the second task,

the wall-sit task.

Legs gave out before I wanted to.

After analysing the results, it's time to reveal to our volunteers

what today has really been about.

Now, you came here thinking this had something to do with exercise,

efficiency, better ways of doing exercise.

Actually, it has absolutely nothing to do with that.

THEY CHUCKLE

Who here went into a room where there were some biscuits?

Oh, are you beginning to get a hint here?

That is part of what we were looking at.

We were actually looking at willpower.

For two people, there was very, very large effects,

where you had big decreases from your first wall sit

to your second one in the cookie group.

So, within your group, who do you think it was?

I think I was.

-You think as well?

-It might have been me.

OK. Was it out of those two?

It was...Giuseppe...

-..and Ian...

-THEY CHUCKLE

..who were... Yeah, you absolutely replicated the effects well.

Huge decreases from your first to second wall sit.

All the volunteers in the room without the cookie temptation

lasted just as long in the wall sit as they did at the start of the day.

But Ian and Giuseppe,

after manfully resisting the delicious smelling cookies,

managed 30 seconds less than they had previously.

This experiment was based on a renowned psychology study in the US.

We're trying to replicate an effect that's been shown in the research

where, when you use willpower once, you will use less the second time.

So you'll give up on the wall sit a lot quicker,

because willpower reduces over time.

So if you think about the cookies in your experiment,

equate that to the sofa for exercise.

The sofa is the cookie.

-Get rid of the sofa.

-Get rid of the sofa!

Or at least don't go into that room where the sofa is,

or go straight to the gym after work.

What are the temptations in your house and think,

"OK, how can I avoid those temptations?

"Can I remove those temptations?"

Basically, make sure there's no wine in the house, then, as well.

If you're relying on willpower for you to exercise,

it will probably fail.

If willpower isn't a good motivator, what is?

What you need to do is to look at more immediate satisfactions.

A podcast while you're walking or if you enjoy the company

of the fitness instructor, what do you enjoy?

If you fancy the fitness instructor...

I didn't want to say that!

Sometimes you have to get motivation

for doing stuff with other people, don't you?

I find I'm far more motivated to go

if it's with somebody else. If it's by myself, there's no chance.

If you really enjoy your daughter's company or your friend's company,

then it's short-term satisfaction.

They will keep you going.

It's the enjoyment and the value of that exercise,

rather than the guilt or other people telling you to do so.

If you don't enjoy going to the gym, don't go to the gym.

Find something else that you DO enjoy.

So the secret of willpower is not to need it in the first place.

Another reason some of us are reluctant to exercise

is a fear of doing ourselves damage.

And there's one activity that has a particularly bad reputation,

especially for our joints.

But new research

could be about to turn this fear of running on its head.

Running is good for your heart and your lungs.

But there are many people, including me,

who worry that it's bad for the joints,

particularly the knees.

Is this true? I'm about to find out.

I've come to St Mary's University in London

to meet Professor John Brewer,

exercise scientist and running enthusiast.

I'm pretty convinced that when I run, when I exercise,

it leads to potential injuries to the knee.

Because it makes sense, you're pounding away on the concrete.

-Yeah.

-And that sends shocks through your knee,

and that adds to wear and tear, osteoarthritis and things like that.

That's an easy assumption to make,

because of course there'll be forces going to the foot, the lower leg,

and the knee when you're running.

And it's thought that those forces

will damage this all-important cartilage

that rests between the bones of the knee.

We're doing an experiment to measure the forces that go through our knees

when we run, compared with walking.

And I'm the guinea pig.

John is using motion capture technology.

This helps him to see exactly how my body moves.

My first challenge is an easy one.

So you're going to walk along the track here.

We've got two force platforms.

They will measure the force every time your foot hits the ground.

So just walk naturally, look ahead,

nice and steadily down towards the camera at the end there.

-Take your time, off you go.

-OK.

I'm glad there aren't any mirrors in here,

as I don't think this is a good look.

First, walking.

By analysing my movement and the forces going through my joints,

this will allow John to measure how much impact and potential damage is

happening to my knees.

Now for something a little more energetic.

OK, Michael, so this time we're not going to walk.

We're going to ask you to run. In your own time, a nice...

No, no, no. Definitely not, not Usain Bolt.

-More Mo Farah.

-OK.

-OK.

Even Mo Farah is probably about three times as fast as I am.

-Yeah, yeah.

-By tracking my running movements,

John can see how they compare with walking.

So which causes the greatest impact on my knees,

running or walking?

John has analysed the results.

We have two lines here. This first red graph shows the forces that your

foot encountered when you were running,

and the blue one is when you're walking.

The forces from running were higher

than the forces from when you were walking,

when you were going much more slowly.

So that one is nearly twice as big as that one?

Yes, it is. So that would in a sense play into the hands

of the theory that running causes a lot of extra force and more damage.

Yeah.

As you might expect, at the moment I hit the ground, the forces going

through my knee are greater when I run than when I walk.

But John has also compared how much time my knees

experience that impact.

What's really interesting is that when you look at this a little

bit more closely, you can see that the length of time that your foot

was experiencing force for

was much longer than when you were walking.

We can actually see that the force per metre, from running,

was significantly lower,

almost half the force from walking.

OK, I find that very surprising, I must admit.

Mmm, it is, it's a big surprise,

but it's a function of the speed that you're going at,

your stride length, and the shorter period of time

that your foot is in contact with the ground.

When I ran, my foot touched the ground for less time

and I made fewer steps in total.

This means that, overall, the force through my body

was actually lower for running than it was for walking.

It's still the case that when I was running, there was more sharp impact

and, you know, if I punch you hard

or I punch you more gently but slower,

you're still going to feel the hard punch much more than the gentle one

which goes on for a while.

If we look at the peak force,

that's actually quite acceptable a force

because it's the sort of force

that the human body is designed to experience.

We are all designed to both walk and to run.

We had to run, you know,

our ancestors had to run in order to catch food or to avoid being prey.

So running is a natural part of our lives.

So the type of force that we see is not excessive.

When it comes to our knees,

John doesn't simply believe running is harmless.

He believes it might actually be beneficial.

Scientific studies suggest that the regular impact from running

repeatedly compresses and releases the cartilage.

Surprisingly, that's actually good for the joint.

One of the benefits is that the regular impact from running,

actually, are compressing and then relaxing the cartilage.

That's stimulating blood flow,

it's bringing more oxygen and nutrients to the cartilage,

and of course that will help it to both repair,

and to grow and to develop.

-So not an excuse?

-Not an excuse at all.

Get your training shoes on and get out for a run.

New research shows that runners are in fact less likely to suffer

from arthritis than non-runners.

So it would seem that in the long term,

running can be good for our joints.

But I know all too well there are plenty of other ways

that you can injure yourself while running.

I managed to injure my knee while running.

I was going through a wood, I sort of slid on something, twisted it,

-and it hasn't been the same since.

-Injuries are an occupational hazard,

they will always happen to anybody in sport,

particularly at higher risk in running,

when you're on an uneven or slippery surface.

But I think what we've seen today is that the scientific evidence

shows that, actually, running can be good for you,

particularly if you start off slowly and build up gradually.

A mistake that many people make is to do too much, too soon.

The most common cause of injury is trying to run too far or too fast

before your body has had a chance to get used to it.

So start with brisk walking,

and build up distance and pace gradually.

If you are very overweight or have an injury,

then you might be better off doing something like cycling or swimming.

But for most of us, a small amount of running

can be good for our health and our knees.

So the claim that running, at least in moderation,

leads to wearing out of the joints and possibly to arthritis,

turns out to be false.

Another excuse for not doing exercise bites the dust.

Most people exercise to improve their health, lose a bit of weight,

and tone their bodies.

But some people, and they can be very annoying,

do exercise just because they love it.

New science is beginning to explain why exercise can be so pleasurable.

Many runners claim that when they go for a run,

they get this runner's high,

the release in the brain of feel-good chemicals,

a bit like illegal drugs,

which just makes them feel terrific.

Now, I have never experienced anything like that,

so can it possibly be true?

For a long time, it's been claimed that the runner's high

is the result of endorphins,

something our bod produces during exercise.

But now, physiologist Dr Saoirse O'Sullivan

believes a different brain signal may be responsible,

one that is very similar to an illegal drug.

So I'm interested in a class of chemicals called endocannabinoids.

And these are presumably like cannabis?

So they're...they're similar in structure to the main chemical

that you find in cannabis, but we make them in our own body.

We're interested in whether or not these chemicals

might be part of the high.

To find out, we're doing a brand-new experiment

with the help of some runners in Nottingham.

Saoirse is going to see if the level of endocannabinoids in their blood

increases after they've been for a run.

-Has this been done before?

-It hasn't been done

in an outdoor setting before, so there's been a couple of studies

that have been done, but they were in a laboratory setting,

and they've actually got them to exercise

for quite a long period of time.

We want to find out if you can get an increase in endocannabinoids from

the sort of easy short run that you or I might do in the local park.

I think it's probably time for you lot to go off.

-I'll see you back here in about half an hour.

-OK.

-OK.

-Enjoy.

-Good luck.

-You look as though you're quite jealous.

I am, really jealous. I'd like to be doing that now.

Whereas I absolutely wouldn't.

The idea that cannabinoids might increase during exercise is new.

These natural brain chemicals were discovered by accident

when scientists were researching why the drug cannabis makes us high.

They first discovered that there is a specific receptor in the bodies,

so a protein found on the outside of cells, to which the chemicals from

cannabis combined and that's what brings about their actions.

And once they knew that we have this in our brain,

people started looking for, what do we make in our body

that binds to this?

Because we don't have proteins and receptors that bind to cannabis

for no reason. We must make some chemical in our body that also binds

to them that might have similar effects.

And it was just a couple of years later

that they discovered the first compound

that they called anendocannabinoids.

The image on the right is a cannabinoid from cannabis,

on the left is an endocannabinoid we produce in our body.

They're almost identical.

They're structurally very similar.

They're very similar compounds,

have very similar pharmacological properties.

Both chemicals put out positive emotions and increase appetite -

sensations that people report after they've been for a run.

OK, whoa, slow down. Well done, how are you feeling?

Really good. Really exhilarated, actually.

I feel tingly, warm, light on my feet.

Good, alive, pumping.

But is their euphoria due to a rise in endocannabinoids?

We are about to find out.

Their blood samples are analysed.

And the results are in.

And what we found was, when you came back from the run,

you had 30% more endocannabinoids in your blood than you did.

So exercise seems to stimulate across all of you

a big increase of endocannabinoids in your blood.

-Surprising?

-That's very surprising.

That is surprising, isn't it? That proves what I thought,

-to be honest with you.

-Yeah.

-Yeah.

More of a runner's bliss than a runner's high, maybe.

So even a relatively short run can bring chemical bliss.

But why do people produce endocannabinoids when they exercise?

Saoirse believes it may be our body's way of encouraging us

-to keep fit.

-Now we know exercise is good for us,

we know that we're fitter and healthier.

We're mentally and physically healthier, we're more fertile,

and there's lots of reasons why exercise is good for us.

So the body having a reward mechanism for exercise would seem

like a good evolutionary thing that, you know,

just makes us want do it more,

and that makes us fitter and stronger and happier.

So how is getting, you know, a bliss from doing exercise different to,

for example, from smoking cannabis?

So I think probably the big difference

is the amount of these chemicals.

So you've got a 30% increase.

It caused a mood-altering effect in you, it made you feel better.

But if you were to smoke a cannabis cigarette or joint,

you would have a much, much bigger increase and that can have a lot of

negative impacts on some people as well.

Taking in too many cannabinoids can overwhelm our system.

But when our bodies produce cannabinoids,

it keeps them within safe limits.

So we experience a high without the downsides.

Now, I have always been rather cynical about the idea

of a runner's high, having never personally experienced it.

But this new research really does suggest there may be

naturally occurring chemicals that can help explain

why some people really love exercise.

So far, we've been looking at the science of how good

exercise is for our bodies, but some of the most exciting new research

is looking at the impact it can have on our brains.

In this final test,

I want to look at an exercise that may be able to make us

instantly cleverer.

Now, there is plenty of evidence that exercise is good for the brain

but there is one particular activity

which seems to be unusually beneficial,

and we're about to test it out.

SALSA MUSIC

I've come to Coventry University to meet a team of scientists

who want to test whether our brains get an immediate boost from dancing.

Cognitive scientist Professor Michael Duncan is running

the experiment.

OK, I must admit it is a great deal more fun seeing them doing this

than being on a treadmill, or something like that, but why dance?

Dance is physically active but it's also very co-ordinative.

It has a cognitive element in order to accomplish that.

You have to use your brain, basically, to remember the steps,

-and things like that.

-Yeah.

-So what you're going to be measuring

is the effect, if you like, of doing a dance class on your brain.

If we give somebody one session,

does that produce an immediate response?

They're obviously enjoying themselves.

The question is, is it actually making them in any sense smarter?

Yes.

SALSA MUSIC

Helping Mike with the experiment is salsa instructor

and exercise scientist Dr Pablo Domene.

He's invited his entire dance class to the lab.

What keeps you coming back?

Like, the power, the atmosphere, enjoyment that you come

and you don't want to finish.

Do you feel smarter afterwards?

I'm not sure about smarter.

You have a much better spatial awareness and much better reflexes.

These dancers will do some mental tests before and after

a dance session to see if there's any change in performance.

So, we've got one which looks at decision-making

and ability to avoid distractions.

We've got another one that looks at working memory

and can you recognise patterns, and we have another one

that looks at, can you anticipate moving objects?

So it's basically being able to anticipate something

in space and time, if you like?

It has wide application in a whole range of different parts of life.

The test assesses skills we use every day - decision-making, memory,

and our ability to judge how fast things are moving through space.

Now the volunteers have had their brains assessed,

it's time to test their feet.

As the class progresses, the music gets faster, and so do the moves.

Con brazos!

Everyone is building up a sweat.

Salsa basica.

After 30 minutes of high-paced salsa...

..it's time for everyone to repeat the mental test.

So, did the dance class make any difference?

Mike has the results.

The anticipation timing task,

which looks at the perception and cognition together,

we found an 8% improvement pre to post for the whole group.

-Pretty good?

-Yeah, pretty good.

For the visual discrimination test,

where we're looking at can you focus and avoid being distracted,

-we saw a 13% improvement which, again...

-I could do with that.

I find I get distracted by all sorts of things when I'm at work.

-So, yeah.

-The test that's probably more surprising to me

and the biggest change is the one that looked at working memory,

where we found an 18% improvement in that particular test.

Working memory is our ability

to hold different bits of information in our heads

and use it to get the job done,

anything from following a recipe to holding a conversation.

And Mike has never seen a result like this for any other type

of activity, including running and cycling.

It's so amazing to see the results because I just think

I just shake, shake, shake.

But actually, to know, wow, I'm getting smarter!

I think cognition, the ability to repeat something, I think

it is a great asset at work.

So, what's special about dancing?

Most types of exercise will have a positive effect

on cognitive performance.

With something like salsa dance, you have to think about these steps,

you have to think about the pattern, you have to think about

staying in time with the music,

so that actually requires a lot of cognitive manipulation

while the dance is going on,

while you are also physically exerting yourself.

One reason people say they don't do exercise

is because they ain't got time,

but presumably this would suggest that if you put...

find a bit of time to do a bit of dancing, then you might become

a bit more productive and therefore you might get more out of your day.

You become more effective in your use of existing time.

So, dance, it's like that.

Snap. Snap, snap. OK.

One, two. One, two.

Exercise really can make us quicker. And perhaps cleverer.

And current research suggests

that dancing could be the best exercise of all

to get maximum brain benefits.

Focus! Five, six, seven, eight. One, two, three. And shimmy!

No, that's really good, that's really good.

Whoo!

I've come to the end of my search

into the most effective ways to get fit.

I've been really impressed at the scientific breakthroughs

that are helping us to understand exactly how exercise gives us

all these wonderful benefits, and this new knowledge means

we can be more targeted when choosing the right activity for us.

So, what have I learnt about getting fit?

If lack of time is your problem, then the intensity is the way to go.

Brisk walks, some Hiit and also some weight training.

I'm never going to love doing exercise,

but at least I now know how to do it properly

and how to get the maximum benefit for the minimum effort.