Ask the Doctor (2017–…): Season 1, Episode 8 - Genes - full transcript
Dr Shalin Naik debates the ethics of having his genomes sequenced. What could the consequences be if he proceeds with the test?
[Renee] Most of us would like
to remain active and healthy
for as long as we live.
Research shows that
one of the best ways to do that
is to get moving.
But despite this, globally,
one in four adults isn't active enough.
So in this episode, we ask,
why should we exercise?
As Sandro finds out how much we need
to combat one of the most serious
health issues of our time.
Some scientists are suggesting that
sitting might be the next smoking.
[Renee] What is it about exercise
that helps combat depression?
I myself have had experiences
of depressive episodes,
and interestingly,
I've turned to exercise every time.
And there's some good news
for all of us,
when Shalin discovers how much exercise
is enough to keep us healthy.
There's almost no room
for your lung in there!
[theme music]
[Shalin] I cycle to work most days
and keep moderately active.
But is that enough
to prevent health problems
such as cardiovascular disease,
high blood pressure and stroke?
I'm hoping the Baker Institute
will have the answers.
They'll push me to the max
in two exercise-based tests,
where the health of my heart
can be measured
by how much oxygen it pumps
through the body via the bloodstream.
Does being fitter mean
you're also healthier?
And finding that out
is making me feel a bit nervous.
The man who'll be putting me
through my paces
is cardiologist Professor Andre La Gerche.
He's also a gun marathon and trail runner.
There is one little thing
that I haven't told you.
- OK.
- We need a comparison for this test,
and so I've enlisted the services
of a colleague of mine,
Dr Mitch Anderson.
He's both a medical doctor
and an elite endurance athlete.
He broke the world record for cycling...
just under 500km in 12 hours,
averaging 42km an hour.
Really a Herculean feat.
- That's the comparison?
- That's the comparison.
[Shalin] Oh.
- Morning!
- How are you?
- Dr Mitch.
- Oh, sweaty palms. Good to see.
- Oh, gee.
Mitch, looks like you're all ready to go.
I've got my ECG dots on, which means
that we need to get yours on as well.
There's a slight difference
in follicular composition going on.
OK, we have a modern medical device
called a shaver, that's gonna--
Oh, great.
...that's gonna help us around
that little problem.
[Shalin] This might seem like
ritual public humiliation...
Ahh! [chuckles]
...but actually, it's for a VO2 max test.
The VO2 max test
measures the amount of oxygen
our body can effectively use
when pushed to the max.
It's the closest thing we have
to a crystal ball in medicine,
and is the best predictor of things
like how long you're going to live,
your risk of heart attack,
your risk of stroke,
and lots of these very important
health outcomes.
[Shalin] OK, I'm pumped.
May the force be with me.
[Mitch, in deep voice]
Shalin, I am your father.
[laughs]
[chuckling] Oh, God...
Who brought this guy? Seriously.
So, we'll get you both
to start cycling for us.
[Shalin] Because Mitch is
Mr Elite Athlete,
this test will establish whether
he's healthier than Mr Ordinary... me.
He's definitely trying to psych me out.
He's obviously worried
about the competition.
[Mitch] How you feeling?
[Shalin] Ah, it's alright.
The seat's pretty...
It's cutting into something.
[Mitch] You can get numbness
in your undercarriage.
[Shalin] Undercarriage?
[Mitch] Yes.
[Shalin] Bloody hell.
[Andre] At the moment,
you're both at 56 watts,
and that's just increasing
a few watts per second.
[Shalin] Both Mitch and I
have to cycle non-stop until we can't,
with the resistance in the pedals
increasing steadily as we go.
I can feel the resistance rising.
And all of a sudden,
more than my undercarriage is hurting.
I'm starting to breathe a little bit
more intensely now,
which means my heart has to pump
a bit harder
to deliver the oxygen my muscles need
to keep going.
[Andre] So, at the moment,
you're both doing 138 watts,
so now this is really a moderate level
of exercise.
[Shalin] Mitch, on the other hand,
hasn't even raised a sweat,
so already it looks as if
his heart function is better,
because he's a whole lot fitter.
So, what we can see is that
as the intensity of cycling is increasing,
Shalin is using progressively more oxygen
and also more carbon dioxide,
which is this blue line here.
173 watts.
[Shalin] It's getting tough.
[Mitch chuckles]
175 watts.
Now you can hear that Shalin is breathing
more strenuously.
He's no longer able to get enough oxygen
for the muscle needs,
and at the same time, we can see Mitch,
who's pedalling at
exactly the same wattage...
and he's still breathing
really quite comfortably.
[Shalin] That's because,
as an elite athlete,
Mitch's heart,
which is a muscle, after all,
is far stronger than mine,
and able to deliver oxygen
via the bloodstream
much more efficiently than the heart
of an everyday cyclist like me.
[Andre] Keep it going.
You're doing really well.
Keep it going, Shalin.
You're doing really well.
OK, good job.
I'm going to take this mask off.
We've got all of the information
that we require.
[Shalin breathing heavily]
You've done a superb job.
But as you can see,
there's quite some variability
in the degree of fitness
that can be achieved.
That was pretty hard.
At the start it was fine,
but as it went on,
you could feel your thighs
and your calves kind of burning.
I mean, I definitely noticed my
breathing rate going up tremendously
and ordinarily if I get tired,
I just take a 30-second break
and then keep going,
but the point of this test is to not stop.
It was hard. It was really hard.
Mitch, on the other hand,
has been cycling already
for another six or seven minutes.
He's used twice the amount of oxygen.
He's approximately twice as fit.
So I think now, Mitch is really
in the hurt locker, as you'd say.
[Shalin] Ha! Took him long enough.
[tense electronic music]
[Mitch straining and breathing heavily]
[Shalin] Come on, buddy.
Just a little bit more.
Just a little bit more. You got this.
[Mitch groaning]
[Andre] OK, and we're done.
Great job. Fantastic work.
Dude. That is impressive.
[groaning and panting]
Coffee time?
[Shalin laughs] Coffee time.
- Good job.
Oh, mate, that was seriously impressive.
I feel like I witnessed a feat
of human nature right there.
What was my score
and what was Mitch's score?
So, your score was just under 40mL
per minute per kilogram
and Mitch achieved 72mL
per minute per kilogram.
[Shalin] Right. That's incredible.
Because Mitch is way fitter than I am,
his heart is working
more efficiently than mine
in pumping life-giving oxygen
around his system.
His cardiovascular health
is obviously fantastic,
but does my moderate level of fitness
mean I'm unhealthy?
The answer comes as
something of a surprise.
[Andre] The health benefits
of 72 versus 40,
the improvement in health outcomes
are very modest.
Right.
On the other hand,
the difference is below your level,
and the health benefits in moving from
being sedentary and unfit
through to moderate fitness
are really massive.
So, if you're less than Joe Average,
go get your lifestyle sorted out.
If you're Joe Average or above,
keep up the good work,
but you don't have to go to the extremes
that this guy goes to.
[Andre] Exactly.
[Shalin] In a little while,
I'll be going up against Mitch again,
this time to see how exercise
can actually change
the physical appearance of the heart.
But if even moderate exercise
has such positive health benefits,
what are the consequences
of being sedentary and unfit?
[Sandro] Think about it.
If you add up all the time you spend
sitting at work,
watching TV, playing computer games,
using the internet, reading books,
driving a car, eating food,
your total daily sitting time will
probably be somewhere within the average
of 8 to 12 hours a day.
The moment your butt hits a seat or couch,
electrical activity in your leg muscles
shuts down.
In addition, the energy your body burns
drops from 99 calories per hour
to 78 calories per hour,
which doesn't sound like much,
but across an 8-hour work day,
it adds up to 180 calories.
Additionally, levels of
fat-burning enzyme lipase
falls by 90%.
In the long term,
hours of sitting every day
will deliver a whole catalogue
of negative health outcomes.
Weaker bones and muscle loss
will make it harder to do everyday things
and keep weight off,
let alone more substantial exercise.
Then, there is the alarming trifecta
of increased risk of heart attack,
stroke and Alzheimer's.
The only reliable way to avoid
these health risks
is to get up and about more often.
Walking for an hour a day
can wind back the risks
of heart attack and stroke
by as much as 50%.
Oh, yeah, and maybe once in a while,
try switching off the...
[exhales] Well, if that's not enough
to get us moving,
we asked those of you who are
already active for some inspiration.
How does exercise benefit you?
[Sandro] With a growing epidemic
of extra kilos in our society,
some scientists are suggesting that
sitting might be the next smoking.
It's estimated 5.9% of all deaths
is attributable to daily sitting
and when you put that into comparison
with some of the other figures,
such as obesity and lack of exercise,
that's comparable to the contribution
that those other conditions make.
[Sandro] So I want to find out
exactly how much,
and by how much, I mean how little,
exercise we need to stay healthy.
Now, if you're anything like me,
it can be tough to find a whole hour for
exercise each day in a busy working week.
But you might remember a bunch
of headlines from a while back
spruiking a revolutionary
daily seven-minute workout.
And I just have to know
if it's too good to be true,
so I'm going to exercise for science.
Let's do this thing.
The original short-duration,
high-intensity workout plan
was published by the American College
of Sports Medicine
and consists of 12
high-intensity exercises
you do for 30 seconds each.
[panting]
OK, that was actually a lot more tough
than I thought it'd be.
My arms are aching and I'm pretty tired.
But is this seven admittedly tough minutes
really enough exercise to wind back
the accumulated health impacts
of sitting for eight hours a day?
If you think across a 16-hour waking day,
that seven minutes
is just a small fraction,
and it's questionable whether
that seven minutes of activity
is sufficient to offset
what happens after,
in that non-exercise period.
[Sandro] Which is interesting,
because if you go back to that original
publication of that seven-minute workout,
it actually encourages people to repeat it
three times each session,
which is more like 21 minutes of exercise,
something the coverage
largely failed to mention.
So, maybe it's best to think about
the seven-minute workout plan
as a starting point on your path to
30 minutes, 5 times a week,
especially if it's been a while since
you got any exercise.
And I guess for me,
that means I've got another two rounds.
One, two...
[Shalin] I'm at the Baker Institute,
where I've learnt that
even moderate exercise
has positive long-term health outcomes.
That was pretty hard.
As it went on, you could feel your thighs
and your calves kind of burning.
I'm now about to go
up against Mitch again,
to see what exercise does to the heart
and what that tells us about our health.
It's a little bit like,
do you go and look at a car
and see how well it runs
by looking at it in the garage,
or do you take it for a drive
down the road?
[Shalin] Looks as if Mitch
is still in his garage,
so I'll go ahead and start my engine.
[Andre] Now, I'm going to give you these,
which will be your hand grips
to hold onto.
[Shalin] I'll be cycling while in an MRI,
a magnetic resonance imagining scanner
that will show images
of my beating heart in real time.
Extraordinary!
[female voice] Please breathe in.
Breathe out, and hold your breath.
[Andre] This is a good view
of Shalin's heart.
This is very normal function,
a normal-looking heart.
So, Shalin, I'm going to get you
to start cycling for me,
and I'm just going to gradually increase
the work that you're doing
up to the first level,
and then I'll let you know.
Brilliant. You're doing a great job.
That's the first level.
From here on in,
you keep pedalling until we stop.
When he's completed
this level of exercise,
after about 2.5 minutes,
we're going to increase
to the next level of exercise,
and then he's done.
[Shalin] Now, this is more my speed.
I'm a laid-back kind of guy, anyway.
Shalin, you're doing really well.
We're just going to bring this up
to the second level.
There's about two minutes to go.
You're doing an extremely good job.
[Shalin]
This isn't quite as easy as I thought.
The only good thing about this now
is that I'm lying down.
[Andre] Twenty seconds to go
till we're finished.
Well done. Your day's done
and you can stop now.
I'll get you to grab a seat here.
[Shalin] Well, that's me done.
Oh, man, that's tight in there.
There's no space to cycle,
and my muscles aren't used to cycling
in those kind of smaller...
[Andre] Circles.
- Small circles.
It is one of the stranger
modes of exercise,
but you're working hard,
and we see that on the pictures.
We see the heart working hard.
- So you can see my heart pumping?
- Absolutely.
- Wow.
- Yep.
[Shalin] Wonder how the champ's
gonna cope with this?
[Andre] Mitch, all's good?
[Mitch] Yep.
I'll get you to start pedalling for me
and I'm just going to gradually
bring it up to the first level.
OK, that's brilliant.
Just bringing it up now.
[Shalin] Look at him go.
Unless you're a cardiologist,
or have witnessed open-heart surgery,
like me, you'll have never seen
a living, beating human heart before.
[Andre] OK, so that's the first level.
So, is the level one for him
the same as it was for me?
No. So, he's now doing your highest level.
Right, that's his low level.
- Yes.
- Fair enough.
[Andre] So, he's exercising flat-out.
You can see his diaphragm
and he's breathing up and down
'cause he's exercising quite hard now.
[Shalin] I mean, it's such
an incredible thing to see live,
the heart pumping live. It's...
It really is remarkable.
We have not been able to do this with any
other imaging modality in any other way.
[Shalin] In our first test,
we saw how Mitch's heart performed better
than my moderately exercised muscle.
So no surprise
it's out-performing mine again.
[Andre] OK, and you can stop.
Brilliant job.
[Shalin] But now for the moment of truth.
Does the heart of an elite athlete
look any different?
[Andre] So,
if we compare the two hearts here,
firstly this is the whole chest cavity
with the lungs,
which is this black bit,
and here is the heart.
Now, if we then compare that
to Mitch's heart,
you really can quite easily appreciate
that Mitch's heart is considerably larger.
There's almost no room
for your lung in there.
It almost looks like there's a battle
for space in the chest.
[Shalin] Yeah, right.
[Andre] You can see this is normal,
normal function.
The heart is squeezing down nicely.
And then if we look at Mitch's heart,
and with every stroke of the heart,
Mitch's heart is pumping out
- twice as much.
- Wow.
It's kind of like you've got a Vespa,
and I've got, like, a Triumph.
[Shalin] Mitch's heart was pumping
a staggering 30L of blood per minute.
That's 2L every 4 seconds.
One, two, three, four.
Amazing, huh?
Mitch's elite-sized heart
is evidence that, like every muscle,
the ones in our heart can grow stronger
and more efficient with exercise.
Even us mere mortals
have a very good chance of preventing
cardiovascular disease
if we maintain a moderate level
of exercise.
So, what's your exercise regime?
[Renee] We've learned about
the payoff our bodies get from exercise,
but what about its impact
on our mental wellbeing?
Depression's actually quite common
in our society,
and I myself have had experiences
of depressive episodes.
And interestingly,
I've turned to exercise every time,
not always consciously.
What I remember about exercise is kind of
laughing and crying at the same time,
and I actually think
that was pretty therapeutic.
To find out more about the link
between exercise and depression,
I'm meeting Dr Stephen Carbone,
a GP who heads up research and evaluation
at beyondblue.
We know that exercise
can help with depression,
but why do we think that is?
Some people think it's got to do with
the changes that exercise can lead to
in the brain's chemistry.
- Things like endorphins--
- Serotonin.
...serotonin, dopamine.
The sort of 'happy' hormones.
Other people think it might be
something to do with
the body's stress response system.
- So, changes in hormones such as cortisol.
- Mm-hm.
And the other theory is that
it might have something to do with
the body's immune system.
Of course, right.
So that it sort of damps down
harmful inflammation
that can affect different parts
of the body,
including our brain
and our sort of circuitry of the brain.
[Renee] Clinical trials confirm exercise
helps people suffering from depression,
but so far, no-one knows for sure
what it is about being active
that actually works.
So, the fascinating thing about
the value of exercise, though,
it's not just biological, is it?
Look, I think it's party that exercise
is something fun, pleasant,
relaxing, de-stressing for people to do,
so there's some natural benefits
from that perspective.
But it's also that, you know,
sometimes if you set yourself some goals
for your exercise,
you're trying to get fitter,
healthier, et cetera,
I mean, that helps to sort of build your
sort of self-confidence, self-esteem.
You've accomplished something.
You're doing something purposeful
and, you know, important to you.
But there's also the social aspect.
I mean, look, many of us like to,
you know, walk with others,
go to the gym around other people,
join classes with other people.
[Renee] Play sports.
[Stephen] Team sports, exactly.
So there's a social element to
sort of physical activity, too,
that also seems to be important.
In fact, some of the research has
looked at prescribing exercise in groups,
and so the benefits
of not just the exercise
but the sort of social connectedness
that comes with that as well.
You know, we all do better
when we're around other people.
[Renee] Mmm.
More than 300 million people
are now living with depression.
So Dr Stephen's research is
crucially important to so many of us,
either because we're dealing with
depression ourselves,
or we're supporting someone who is.
Twenty-one years ago,
Jeremy Suggett was an
18-year-old budding sports star
when he was overwhelmed by the black dog.
I was trying to go back to playing
State League soccer.
- Oh, wow.
- And I just wasn't...
I just wasn't into it.
I think it was the constant fatigue,
being tired all the time.
And also losing interest
in something I loved.
When you play a sport from a young age,
five, six, seven days a week,
and you think that's what you want to do
as a career or something at a high level,
and then all of a sudden
you're just completely...
It's like overnight,
it literally feels like overnight,
you don't want to ever do it again.
I mean, did you have that
sort of feeling about other things,
or were you just not that kind of person
before?
I just wasn't that kind of person before,
and I was very energetic,
into everything, ready to go.
You know, I'd go to the gym,
I'd be a high-energy...
you know, a high-energy person.
[Renee] Fortunately for Jeremy,
he had a good relationship
with his proactive GP.
He was very big on,
"OK, the first thing you need to do is
get back into some form of exercise."
And even though the thought of it
at the time just made me cringe,
that was the first port of call.
[Renee] For someone who'd been
good at sport all his life,
Jeremy's reluctance to exercise was
a measure of just how down he really was.
But he picked himself up
and tried every form of exercise he could.
Also some psychotherapy,
a bit of that involved as well,
and on top of that, slight medication.
So we're talking the lowest
of lowest ends.
[Renee] Along with incidental
or everyday activity,
Jeremy eventually developed
an exercise regime that worked for him.
So, how much exercise
do you do in a week?
[Jeremy] Well, I'm doing jujitsu
five or six days a week.
- You serious?
- Yeah, so for an hour at a time.
I do, like,
an hour personal training at the gym
and I'll maybe do an hour
by myself at home.
So I try to do, you know,
six to ten hours a week.
And how about sort of the challenge aspect
of exercise?
Yeah, the challenge
is what drives you back,
whether it's, you know, you're dancing
or if you're trying to get faster
in the pool
or whatever you're trying to do.
You really can't think about anything else
outside of what's going on in your life,
so you're right then and there.
[Renee] And so, what would you say is
the most important thing in helping you
to cope with your depression and anxiety?
[Jeremy] Probably
the most important thing,
and I try and stress this to people,
is having a support network.
You see it at the elite level
with sports people,
that they have a team around them,
that they can't do their best
without a team around them.
And that's the same with people
with mental health challenges.
You have to have that support network.
You have to have your GP
but also your friends and family.
[Renee] It didn't happen overnight,
but his GP's prescribed package of
psychotherapy, medication, and exercise
gradually brought Jeremy's depression
under control.
But he has no doubt
which was the most effective for him.
- And it was the exercise.
- Yeah.
It's always, for me,
given me that bit of rush.
It just gives you the beneficial feelings
afterwards
and helps you sleep better,
helps you with your mood,
and helps you wake up the next morning
feeling good.
So it probably took about, I reckon,
a good two or three months
before that started to kick back in again,
but definitely for me it was the exercise,
yeah.
I've come away with an ongoing respect
for the role of exercise...
not only in maintaining a healthy body,
but also as a powerful tool
in restoring mental wellbeing.
And I'm taking heart knowing that
not only is exercise the best protection
against cardiovascular disease,
but that the biggest bang for the buck
comes from the moment
we get off the couch.
We should all start with some form
of activity every day,
and build up from there to the recommended
30 minutes of exercise
five times a week.
The heart is such an
amazingly responsive organ
and through exercise,
a stronger, fitter heart
is something we should all aim for.
Boom-boom.
to remain active and healthy
for as long as we live.
Research shows that
one of the best ways to do that
is to get moving.
But despite this, globally,
one in four adults isn't active enough.
So in this episode, we ask,
why should we exercise?
As Sandro finds out how much we need
to combat one of the most serious
health issues of our time.
Some scientists are suggesting that
sitting might be the next smoking.
[Renee] What is it about exercise
that helps combat depression?
I myself have had experiences
of depressive episodes,
and interestingly,
I've turned to exercise every time.
And there's some good news
for all of us,
when Shalin discovers how much exercise
is enough to keep us healthy.
There's almost no room
for your lung in there!
[theme music]
[Shalin] I cycle to work most days
and keep moderately active.
But is that enough
to prevent health problems
such as cardiovascular disease,
high blood pressure and stroke?
I'm hoping the Baker Institute
will have the answers.
They'll push me to the max
in two exercise-based tests,
where the health of my heart
can be measured
by how much oxygen it pumps
through the body via the bloodstream.
Does being fitter mean
you're also healthier?
And finding that out
is making me feel a bit nervous.
The man who'll be putting me
through my paces
is cardiologist Professor Andre La Gerche.
He's also a gun marathon and trail runner.
There is one little thing
that I haven't told you.
- OK.
- We need a comparison for this test,
and so I've enlisted the services
of a colleague of mine,
Dr Mitch Anderson.
He's both a medical doctor
and an elite endurance athlete.
He broke the world record for cycling...
just under 500km in 12 hours,
averaging 42km an hour.
Really a Herculean feat.
- That's the comparison?
- That's the comparison.
[Shalin] Oh.
- Morning!
- How are you?
- Dr Mitch.
- Oh, sweaty palms. Good to see.
- Oh, gee.
Mitch, looks like you're all ready to go.
I've got my ECG dots on, which means
that we need to get yours on as well.
There's a slight difference
in follicular composition going on.
OK, we have a modern medical device
called a shaver, that's gonna--
Oh, great.
...that's gonna help us around
that little problem.
[Shalin] This might seem like
ritual public humiliation...
Ahh! [chuckles]
...but actually, it's for a VO2 max test.
The VO2 max test
measures the amount of oxygen
our body can effectively use
when pushed to the max.
It's the closest thing we have
to a crystal ball in medicine,
and is the best predictor of things
like how long you're going to live,
your risk of heart attack,
your risk of stroke,
and lots of these very important
health outcomes.
[Shalin] OK, I'm pumped.
May the force be with me.
[Mitch, in deep voice]
Shalin, I am your father.
[laughs]
[chuckling] Oh, God...
Who brought this guy? Seriously.
So, we'll get you both
to start cycling for us.
[Shalin] Because Mitch is
Mr Elite Athlete,
this test will establish whether
he's healthier than Mr Ordinary... me.
He's definitely trying to psych me out.
He's obviously worried
about the competition.
[Mitch] How you feeling?
[Shalin] Ah, it's alright.
The seat's pretty...
It's cutting into something.
[Mitch] You can get numbness
in your undercarriage.
[Shalin] Undercarriage?
[Mitch] Yes.
[Shalin] Bloody hell.
[Andre] At the moment,
you're both at 56 watts,
and that's just increasing
a few watts per second.
[Shalin] Both Mitch and I
have to cycle non-stop until we can't,
with the resistance in the pedals
increasing steadily as we go.
I can feel the resistance rising.
And all of a sudden,
more than my undercarriage is hurting.
I'm starting to breathe a little bit
more intensely now,
which means my heart has to pump
a bit harder
to deliver the oxygen my muscles need
to keep going.
[Andre] So, at the moment,
you're both doing 138 watts,
so now this is really a moderate level
of exercise.
[Shalin] Mitch, on the other hand,
hasn't even raised a sweat,
so already it looks as if
his heart function is better,
because he's a whole lot fitter.
So, what we can see is that
as the intensity of cycling is increasing,
Shalin is using progressively more oxygen
and also more carbon dioxide,
which is this blue line here.
173 watts.
[Shalin] It's getting tough.
[Mitch chuckles]
175 watts.
Now you can hear that Shalin is breathing
more strenuously.
He's no longer able to get enough oxygen
for the muscle needs,
and at the same time, we can see Mitch,
who's pedalling at
exactly the same wattage...
and he's still breathing
really quite comfortably.
[Shalin] That's because,
as an elite athlete,
Mitch's heart,
which is a muscle, after all,
is far stronger than mine,
and able to deliver oxygen
via the bloodstream
much more efficiently than the heart
of an everyday cyclist like me.
[Andre] Keep it going.
You're doing really well.
Keep it going, Shalin.
You're doing really well.
OK, good job.
I'm going to take this mask off.
We've got all of the information
that we require.
[Shalin breathing heavily]
You've done a superb job.
But as you can see,
there's quite some variability
in the degree of fitness
that can be achieved.
That was pretty hard.
At the start it was fine,
but as it went on,
you could feel your thighs
and your calves kind of burning.
I mean, I definitely noticed my
breathing rate going up tremendously
and ordinarily if I get tired,
I just take a 30-second break
and then keep going,
but the point of this test is to not stop.
It was hard. It was really hard.
Mitch, on the other hand,
has been cycling already
for another six or seven minutes.
He's used twice the amount of oxygen.
He's approximately twice as fit.
So I think now, Mitch is really
in the hurt locker, as you'd say.
[Shalin] Ha! Took him long enough.
[tense electronic music]
[Mitch straining and breathing heavily]
[Shalin] Come on, buddy.
Just a little bit more.
Just a little bit more. You got this.
[Mitch groaning]
[Andre] OK, and we're done.
Great job. Fantastic work.
Dude. That is impressive.
[groaning and panting]
Coffee time?
[Shalin laughs] Coffee time.
- Good job.
Oh, mate, that was seriously impressive.
I feel like I witnessed a feat
of human nature right there.
What was my score
and what was Mitch's score?
So, your score was just under 40mL
per minute per kilogram
and Mitch achieved 72mL
per minute per kilogram.
[Shalin] Right. That's incredible.
Because Mitch is way fitter than I am,
his heart is working
more efficiently than mine
in pumping life-giving oxygen
around his system.
His cardiovascular health
is obviously fantastic,
but does my moderate level of fitness
mean I'm unhealthy?
The answer comes as
something of a surprise.
[Andre] The health benefits
of 72 versus 40,
the improvement in health outcomes
are very modest.
Right.
On the other hand,
the difference is below your level,
and the health benefits in moving from
being sedentary and unfit
through to moderate fitness
are really massive.
So, if you're less than Joe Average,
go get your lifestyle sorted out.
If you're Joe Average or above,
keep up the good work,
but you don't have to go to the extremes
that this guy goes to.
[Andre] Exactly.
[Shalin] In a little while,
I'll be going up against Mitch again,
this time to see how exercise
can actually change
the physical appearance of the heart.
But if even moderate exercise
has such positive health benefits,
what are the consequences
of being sedentary and unfit?
[Sandro] Think about it.
If you add up all the time you spend
sitting at work,
watching TV, playing computer games,
using the internet, reading books,
driving a car, eating food,
your total daily sitting time will
probably be somewhere within the average
of 8 to 12 hours a day.
The moment your butt hits a seat or couch,
electrical activity in your leg muscles
shuts down.
In addition, the energy your body burns
drops from 99 calories per hour
to 78 calories per hour,
which doesn't sound like much,
but across an 8-hour work day,
it adds up to 180 calories.
Additionally, levels of
fat-burning enzyme lipase
falls by 90%.
In the long term,
hours of sitting every day
will deliver a whole catalogue
of negative health outcomes.
Weaker bones and muscle loss
will make it harder to do everyday things
and keep weight off,
let alone more substantial exercise.
Then, there is the alarming trifecta
of increased risk of heart attack,
stroke and Alzheimer's.
The only reliable way to avoid
these health risks
is to get up and about more often.
Walking for an hour a day
can wind back the risks
of heart attack and stroke
by as much as 50%.
Oh, yeah, and maybe once in a while,
try switching off the...
[exhales] Well, if that's not enough
to get us moving,
we asked those of you who are
already active for some inspiration.
How does exercise benefit you?
[Sandro] With a growing epidemic
of extra kilos in our society,
some scientists are suggesting that
sitting might be the next smoking.
It's estimated 5.9% of all deaths
is attributable to daily sitting
and when you put that into comparison
with some of the other figures,
such as obesity and lack of exercise,
that's comparable to the contribution
that those other conditions make.
[Sandro] So I want to find out
exactly how much,
and by how much, I mean how little,
exercise we need to stay healthy.
Now, if you're anything like me,
it can be tough to find a whole hour for
exercise each day in a busy working week.
But you might remember a bunch
of headlines from a while back
spruiking a revolutionary
daily seven-minute workout.
And I just have to know
if it's too good to be true,
so I'm going to exercise for science.
Let's do this thing.
The original short-duration,
high-intensity workout plan
was published by the American College
of Sports Medicine
and consists of 12
high-intensity exercises
you do for 30 seconds each.
[panting]
OK, that was actually a lot more tough
than I thought it'd be.
My arms are aching and I'm pretty tired.
But is this seven admittedly tough minutes
really enough exercise to wind back
the accumulated health impacts
of sitting for eight hours a day?
If you think across a 16-hour waking day,
that seven minutes
is just a small fraction,
and it's questionable whether
that seven minutes of activity
is sufficient to offset
what happens after,
in that non-exercise period.
[Sandro] Which is interesting,
because if you go back to that original
publication of that seven-minute workout,
it actually encourages people to repeat it
three times each session,
which is more like 21 minutes of exercise,
something the coverage
largely failed to mention.
So, maybe it's best to think about
the seven-minute workout plan
as a starting point on your path to
30 minutes, 5 times a week,
especially if it's been a while since
you got any exercise.
And I guess for me,
that means I've got another two rounds.
One, two...
[Shalin] I'm at the Baker Institute,
where I've learnt that
even moderate exercise
has positive long-term health outcomes.
That was pretty hard.
As it went on, you could feel your thighs
and your calves kind of burning.
I'm now about to go
up against Mitch again,
to see what exercise does to the heart
and what that tells us about our health.
It's a little bit like,
do you go and look at a car
and see how well it runs
by looking at it in the garage,
or do you take it for a drive
down the road?
[Shalin] Looks as if Mitch
is still in his garage,
so I'll go ahead and start my engine.
[Andre] Now, I'm going to give you these,
which will be your hand grips
to hold onto.
[Shalin] I'll be cycling while in an MRI,
a magnetic resonance imagining scanner
that will show images
of my beating heart in real time.
Extraordinary!
[female voice] Please breathe in.
Breathe out, and hold your breath.
[Andre] This is a good view
of Shalin's heart.
This is very normal function,
a normal-looking heart.
So, Shalin, I'm going to get you
to start cycling for me,
and I'm just going to gradually increase
the work that you're doing
up to the first level,
and then I'll let you know.
Brilliant. You're doing a great job.
That's the first level.
From here on in,
you keep pedalling until we stop.
When he's completed
this level of exercise,
after about 2.5 minutes,
we're going to increase
to the next level of exercise,
and then he's done.
[Shalin] Now, this is more my speed.
I'm a laid-back kind of guy, anyway.
Shalin, you're doing really well.
We're just going to bring this up
to the second level.
There's about two minutes to go.
You're doing an extremely good job.
[Shalin]
This isn't quite as easy as I thought.
The only good thing about this now
is that I'm lying down.
[Andre] Twenty seconds to go
till we're finished.
Well done. Your day's done
and you can stop now.
I'll get you to grab a seat here.
[Shalin] Well, that's me done.
Oh, man, that's tight in there.
There's no space to cycle,
and my muscles aren't used to cycling
in those kind of smaller...
[Andre] Circles.
- Small circles.
It is one of the stranger
modes of exercise,
but you're working hard,
and we see that on the pictures.
We see the heart working hard.
- So you can see my heart pumping?
- Absolutely.
- Wow.
- Yep.
[Shalin] Wonder how the champ's
gonna cope with this?
[Andre] Mitch, all's good?
[Mitch] Yep.
I'll get you to start pedalling for me
and I'm just going to gradually
bring it up to the first level.
OK, that's brilliant.
Just bringing it up now.
[Shalin] Look at him go.
Unless you're a cardiologist,
or have witnessed open-heart surgery,
like me, you'll have never seen
a living, beating human heart before.
[Andre] OK, so that's the first level.
So, is the level one for him
the same as it was for me?
No. So, he's now doing your highest level.
Right, that's his low level.
- Yes.
- Fair enough.
[Andre] So, he's exercising flat-out.
You can see his diaphragm
and he's breathing up and down
'cause he's exercising quite hard now.
[Shalin] I mean, it's such
an incredible thing to see live,
the heart pumping live. It's...
It really is remarkable.
We have not been able to do this with any
other imaging modality in any other way.
[Shalin] In our first test,
we saw how Mitch's heart performed better
than my moderately exercised muscle.
So no surprise
it's out-performing mine again.
[Andre] OK, and you can stop.
Brilliant job.
[Shalin] But now for the moment of truth.
Does the heart of an elite athlete
look any different?
[Andre] So,
if we compare the two hearts here,
firstly this is the whole chest cavity
with the lungs,
which is this black bit,
and here is the heart.
Now, if we then compare that
to Mitch's heart,
you really can quite easily appreciate
that Mitch's heart is considerably larger.
There's almost no room
for your lung in there.
It almost looks like there's a battle
for space in the chest.
[Shalin] Yeah, right.
[Andre] You can see this is normal,
normal function.
The heart is squeezing down nicely.
And then if we look at Mitch's heart,
and with every stroke of the heart,
Mitch's heart is pumping out
- twice as much.
- Wow.
It's kind of like you've got a Vespa,
and I've got, like, a Triumph.
[Shalin] Mitch's heart was pumping
a staggering 30L of blood per minute.
That's 2L every 4 seconds.
One, two, three, four.
Amazing, huh?
Mitch's elite-sized heart
is evidence that, like every muscle,
the ones in our heart can grow stronger
and more efficient with exercise.
Even us mere mortals
have a very good chance of preventing
cardiovascular disease
if we maintain a moderate level
of exercise.
So, what's your exercise regime?
[Renee] We've learned about
the payoff our bodies get from exercise,
but what about its impact
on our mental wellbeing?
Depression's actually quite common
in our society,
and I myself have had experiences
of depressive episodes.
And interestingly,
I've turned to exercise every time,
not always consciously.
What I remember about exercise is kind of
laughing and crying at the same time,
and I actually think
that was pretty therapeutic.
To find out more about the link
between exercise and depression,
I'm meeting Dr Stephen Carbone,
a GP who heads up research and evaluation
at beyondblue.
We know that exercise
can help with depression,
but why do we think that is?
Some people think it's got to do with
the changes that exercise can lead to
in the brain's chemistry.
- Things like endorphins--
- Serotonin.
...serotonin, dopamine.
The sort of 'happy' hormones.
Other people think it might be
something to do with
the body's stress response system.
- So, changes in hormones such as cortisol.
- Mm-hm.
And the other theory is that
it might have something to do with
the body's immune system.
Of course, right.
So that it sort of damps down
harmful inflammation
that can affect different parts
of the body,
including our brain
and our sort of circuitry of the brain.
[Renee] Clinical trials confirm exercise
helps people suffering from depression,
but so far, no-one knows for sure
what it is about being active
that actually works.
So, the fascinating thing about
the value of exercise, though,
it's not just biological, is it?
Look, I think it's party that exercise
is something fun, pleasant,
relaxing, de-stressing for people to do,
so there's some natural benefits
from that perspective.
But it's also that, you know,
sometimes if you set yourself some goals
for your exercise,
you're trying to get fitter,
healthier, et cetera,
I mean, that helps to sort of build your
sort of self-confidence, self-esteem.
You've accomplished something.
You're doing something purposeful
and, you know, important to you.
But there's also the social aspect.
I mean, look, many of us like to,
you know, walk with others,
go to the gym around other people,
join classes with other people.
[Renee] Play sports.
[Stephen] Team sports, exactly.
So there's a social element to
sort of physical activity, too,
that also seems to be important.
In fact, some of the research has
looked at prescribing exercise in groups,
and so the benefits
of not just the exercise
but the sort of social connectedness
that comes with that as well.
You know, we all do better
when we're around other people.
[Renee] Mmm.
More than 300 million people
are now living with depression.
So Dr Stephen's research is
crucially important to so many of us,
either because we're dealing with
depression ourselves,
or we're supporting someone who is.
Twenty-one years ago,
Jeremy Suggett was an
18-year-old budding sports star
when he was overwhelmed by the black dog.
I was trying to go back to playing
State League soccer.
- Oh, wow.
- And I just wasn't...
I just wasn't into it.
I think it was the constant fatigue,
being tired all the time.
And also losing interest
in something I loved.
When you play a sport from a young age,
five, six, seven days a week,
and you think that's what you want to do
as a career or something at a high level,
and then all of a sudden
you're just completely...
It's like overnight,
it literally feels like overnight,
you don't want to ever do it again.
I mean, did you have that
sort of feeling about other things,
or were you just not that kind of person
before?
I just wasn't that kind of person before,
and I was very energetic,
into everything, ready to go.
You know, I'd go to the gym,
I'd be a high-energy...
you know, a high-energy person.
[Renee] Fortunately for Jeremy,
he had a good relationship
with his proactive GP.
He was very big on,
"OK, the first thing you need to do is
get back into some form of exercise."
And even though the thought of it
at the time just made me cringe,
that was the first port of call.
[Renee] For someone who'd been
good at sport all his life,
Jeremy's reluctance to exercise was
a measure of just how down he really was.
But he picked himself up
and tried every form of exercise he could.
Also some psychotherapy,
a bit of that involved as well,
and on top of that, slight medication.
So we're talking the lowest
of lowest ends.
[Renee] Along with incidental
or everyday activity,
Jeremy eventually developed
an exercise regime that worked for him.
So, how much exercise
do you do in a week?
[Jeremy] Well, I'm doing jujitsu
five or six days a week.
- You serious?
- Yeah, so for an hour at a time.
I do, like,
an hour personal training at the gym
and I'll maybe do an hour
by myself at home.
So I try to do, you know,
six to ten hours a week.
And how about sort of the challenge aspect
of exercise?
Yeah, the challenge
is what drives you back,
whether it's, you know, you're dancing
or if you're trying to get faster
in the pool
or whatever you're trying to do.
You really can't think about anything else
outside of what's going on in your life,
so you're right then and there.
[Renee] And so, what would you say is
the most important thing in helping you
to cope with your depression and anxiety?
[Jeremy] Probably
the most important thing,
and I try and stress this to people,
is having a support network.
You see it at the elite level
with sports people,
that they have a team around them,
that they can't do their best
without a team around them.
And that's the same with people
with mental health challenges.
You have to have that support network.
You have to have your GP
but also your friends and family.
[Renee] It didn't happen overnight,
but his GP's prescribed package of
psychotherapy, medication, and exercise
gradually brought Jeremy's depression
under control.
But he has no doubt
which was the most effective for him.
- And it was the exercise.
- Yeah.
It's always, for me,
given me that bit of rush.
It just gives you the beneficial feelings
afterwards
and helps you sleep better,
helps you with your mood,
and helps you wake up the next morning
feeling good.
So it probably took about, I reckon,
a good two or three months
before that started to kick back in again,
but definitely for me it was the exercise,
yeah.
I've come away with an ongoing respect
for the role of exercise...
not only in maintaining a healthy body,
but also as a powerful tool
in restoring mental wellbeing.
And I'm taking heart knowing that
not only is exercise the best protection
against cardiovascular disease,
but that the biggest bang for the buck
comes from the moment
we get off the couch.
We should all start with some form
of activity every day,
and build up from there to the recommended
30 minutes of exercise
five times a week.
The heart is such an
amazingly responsive organ
and through exercise,
a stronger, fitter heart
is something we should all aim for.
Boom-boom.