- Every time we train, we get worse.
Every time we work out, we get weaker.
It's only when we actually allow ourselves
to recover that we get better,
that we improve, but what is recovery,
'cause it's not just time off the bike.
Knowing when to push and when to ease off
has always been something of an art form.
Recently though, there have been
some big advances in technology,
including around heart rate variability.
They've unlocked some incredible insights
into what actually constitutes recovery.
Now, to find out what that is, we have
been invited out to Boston by industry leaders, Whoop.
They're going to explain the tech,
and just what we can learn from it
in order to optimize our recovery,
and hopefully there are going to be some
easy winds, 'cause having just stepped off
a transatlantic flight, I could really do with some.
(reverb)
(upbeat music)
Before we get on to understanding recovery,
let's get some back story.
Whoop was founded in 2011 by two university students,
a physiology graduate called Will Ahmed is
an athlete himself, and his quest was to be able
to quantify what training was doing to his body.
He then joined up with a mathematics buff
called John Capodilupo.
Their idea was to generate data,
including heart rate variability, using a wristband.
Now this is version one.
It has, as you can see, evolved immeasurably
since those earliest days until now
where you have Whoop 3 point nought.
Now if you keep your eyes on the pro Peleton,
you'll see an awful lot, very high profile riders
unofficially using these.
Same on the off road side of this sport,
that's including World Cross Country Champion
Kate Courtney, and even our own Jeremy Powers.
Now the hardware though is only part of the story.
Whoop's patents lie in the software that goes
with this and allows you to interpret that data.
Firstly, we need to know a little bit more
about HRV, or heart rate variability,
which has been likened to your secret life force,
such is the level of information
you can actually extract from it.
To help explain the science behind it,
we're talking to Emily Capodilupo
who is the director of analytics at Whoop
and also a self-confessed sleep nerd,
which is kind of cool, presuming you're
quite well-rested coming into this one then.
Okay, so.
Perhaps you could start by explaining
actually what HRV is.
- Sure, so, HRV stands for heart rate variability,
and it's a measure of the difference
in timing between successive heartbeats.
So a lot of times you hear from your doctor
that your rest heart rate's 60 beats per minute,
and you might think that you can sort of do
that math and then figure that means
that your heart's beating once a second
on the second, but in reality that's almost never the case.
Sometimes it'll beat after like 1.1 seconds,
sometimes 0.9 and the greater that difference
is between, you know, if you're going
from like 0.9 to 1.1 back to 0.8,
and then up again, or whatever, the higher
the HRV and that's generally considered a good sign.
- In my situation then, so, for example,
I flew over last night, like, I'm pretty jet-lagged.
I got rubbish sleep.
I'm not making excuses again, but what would I expect
to see from heart rate variability then in that case?
So, I would expect to see less heart rate variability?
Yeah. Given that I'm a bit fatigued.
- You'd expect it to be lower because you're
going to be having a stress response to the travel
and to the lack of sleep and to the fact
that your circadian rhythm's thrown off.
So all of that is going to sort of put power
behind the sympathetic side of your nervous system
which is going to suppress the parasympathetic side
and so you're going to start to see
like higher heart rate, lower heart rate variability,
and if we looked at your blood as well,
you'd see higher cortisol levels,
for example, kind of reflecting that.
- And am I right in thinking that
your heart rate variability throughout the day
is less important to what you guys do
with the data than a specific period of time?
- Yeah, so heart rate variability is
like this extremely interesting metric
because it's like anything that affects
your nervous system affects heart rate variability,
but the flip side to that is that it's
somewhat of a non-specific metric.
So, like, if somebody that you're attracted to walks by,
you're going to have like a really strong sympathetic response
and HRV's going to go down for a second,
right, but it doesn't actually mean
that you're less fit or less ready to work out,
right, you're just having a physiological response,
and if you're hot it's going to go down.
If you hydrate, it'll go up a little bit.
And so it's constantly moving throughout the day
based on things that are meaningless,
and so, if like more meaningless things happen
or fewer meaningless things happen,
you're going to have like a higher, or lower average
HRV, and unless we have an insane amount
of contextual data, you kind of can't do that much,
just like knowing what your HRV did
which is why Whoop specifically reports
HRV taken during sleep, when you're sort of
not hyper sensitive to all of these things
that ultimately don't predict something
that you'd be, like, interested in measuring.
Basically, the way that HRV works is
you can think of your body as having
a finite number of resources, and when your HRV
is really high, that means that your body is
sort of in a position where it can allocate
those resources, they're sort of not tied up,
and when your HRV gets low when the sympathetic
nervous system is dominating, it's because there are
physiological requirements on you to do things
that require that active part of your autonomic
nervous system to be running the show,
and so those resources become not available.
So when your HRV is really high,
you can take all these resources that are
ready to be allocated, and say, put them
into your legs and then cycle faster,
and put them into your cardiovascular system
and burn fat, and all the different active processes
that are required that you would kind of want
to put to work in this moment of your workout.
And then after the workout, you have
those resources freed up again to do things
like repair the muscles, and so to convert
that exercise stimulus into a fitness gain.
Now, if your body is sort of busy with things,
like you're fighting off an infection
and therefore, you know, you're sending
those resources to your immune system,
then they're just simply not available
to be allocated towards cycling, or anything else.
And so when you go and try and say,
okay, I'm going to give it all I got,
well, all you have in that moment is maybe 60%,
whereas if your HRV is really high and you can
put all those resources into cycling, then all
you have is maybe 98%, you know, there's
always some has to go to breathing and stuff.
So you're never going to have 100%,
but like, not sort of wasting those resources
on your immune system, things like being stressed
and so having all this sort of like elevated cortisol levels
and all that kind of stuff just means that you
can put them towards your sport,
which is sort of a lower priority thing.
- Okay, so with a Whoop band on we don't need
to check blood or anything, so how is that
actually measuring heart rate variability
and resting heart rate, I can figure,
I can understand that one, but the variability
as well, it's just a like a really accurate
heart rate monitor?
- Yeah, so we use a technology called
photoplethysmography or PPG, and that's the lights
Okay cool. at the bottom.
And so what we do is we shine into your skin,
and it's the very, very, top most superficial
layer of skin, a specific frequency of light.
In our case, it's green, and hemoglobin,
which is the molecule in your red blood cells
that carries oxygen, specifically absorbs
this wavelength and it reflects all
the other wavelengths, and so we have
this little light shining this green light
into your skin and then we have a photoreceptor
which is reading whatever light gets reflected back,
and the difference between what we put in and what
we put out, or what we get bounced back out,
is very cleanly correlated with how much hemoglobin
is directly under the sensor at that moment,
and so as you watch the hemoglobin go up and down,
that's basically caused by the pulses
of your heart rate, and so, PPG is, it's delayed
from heart rate by a couple of fractions
of a millisecond because the blood has
to travel from your heart to your wrist,
but that happens at a roughly constant rate,
and so we can sort of watch your heart beat go by.
So, there's been a bunch of studies looking
at the reliability of PPG as compared to EKG,
and as long as you're sort of getting
a clean signal, they're perfectly comparable.
- Now the hardware element is just one small part
of Whoop, so how do you interpret the data
then that you're getting from the band?
- So, that's really the secret sauce.
So, like, at a super high level, right, we get
this PPG signal, but there's a whole bunch
of different things that can make that signal
difficult to turn into heart beats.
We have a whole signal processing team,
which is like a room of geniuses,
and that's the only thing they work on,
is turning that PPG signal into heart rates,
and we do that better than any other wearable
on the market, partially because it's a team
of geniuses doing hard work, but also partially
because the whole Whoop from the ground up
was designed to optimize this signal.
So we've made different trade-offs
than some of our competitors, things like having
a higher sampling rate, we've hyper-optimized
the specific frequency of light that we're using,
and then just thousands of hours of testing.
And so, we're able to extract every single piece
of information possible from that signal.
- Yeah, the other insights that you've
been able to gather then, because I guess
you've got quite a rich archive of data
on people's recovery and so forth.
So, what other things would an athlete
be able to see and look out for in their own day to day life
that'll help them recover faster,
and therefore train more effectively.
- So, alcohol is obviously one that we talk
about a lot because it more or less has
the same effect on everybody, and it's something
that everybody's kind of familiar with,
so, it's sort of easy to understand.
One of the things that's been really cool
with the Whoop platform is that it can help you
understand not just things that have massive effects,
like binge drinking, but also things that have
really subtle effects, and that maybe have
high inter-person variability in their effects.
So, like, we've had a bunch of people
try mindfulness or meditation at night,
and looked at the effect on their HRV
from that and that effect is really small,
but with a system like Whoop, we can
capture a small effect, and so that's
pretty much across the board helpful,
but then there's other products, like.
Sorry, just go back. It's okay.
- Potentially, doing meditation will
actually improve your recover.
- Yeah.
- Wow.
- Yeah, and that's one of the things
that we kind of love about mindfulness
and meditation is that it's 15 minutes.
It's free.
It's pretty easy, and it makes a difference.
There's so much low-hanging fruit,
like being hydrated, obviously, like, every cyclist
knows it's going to impact performance,
like meditating, you know, even like sleeping
at the same time every night and waking up
at the same time in the morning is,
like, even if you're getting enough sleep
but you're sort of doing it randomly,
by making that sleep more consistent
you're going to see more slow wave sleep,
more REM sleep, higher recovery scores the next day.
So there's like a lot of little things that are
very accessible that Whoop can help you understand.
- Wow, and what about stress and anxiety
then, 'cause I guess that ties in to mindfulness,
can you detect that through heart rate variability
and all the other parameters?
- Kind of, so, like I said, HRV is
a very non-specific metric, so, I don't
know if your HRV is down right now
because you're stressed or because you're hot,
because they're both going to make it go down,
and it's going to go down sort of the same way.
But what we have seen is that if you have
like a sudden life change event,
and all the sudden there's a lot more stress
in your life you'll see HRV fall off that cliff
and stay low, and so what it creates
is not necessarily a immediate, conclusive diagnosis,
but it just opens up this opportunity
to have a conversation, especially with like a coach
who might be on the platform to say,
like, wow your HRV's fallen off a cliff,
as far as I know your training hasn't changed
that much, what's going on, and then like that conversation
can help kind of elicit what's going on.
So, Whoop doesn't really replace humans.
You know, it just kind of helps spark these conversations.
- Are you able to use the information
to perhaps gain insight on a personal level
about what may or may not help,
as well, so you've got the golden rules about sleep
and alcohol, but nutrition's a big one, isn't it?
People often talk about like, oh, I gave up gluten
and I feel better, or I eat more vegetables
and I feel better.
Can the information that Whoop gives you
actually be used as kind of like a self-diagnostic tool
for helping to refine your diet, and so forth.
- Yeah, so the term we use is like self experimenting,
not self-diagnosing Okay.
- 'cause we're not a medical device.
But you can use Whoop to sort of run
these little personalized experiments.
So, let's say for two weeks I don't change
anything, that becomes my baseline,
and then I cut out gluten, and then I can
see, like, did actually anything
statistically significant happen here,
and if it did, great, I've discovered
something about myself, and if it didn't,
then I know that, like, maybe you're gluten sensitive,
and so, just because my buddy's sort of swearing
by this, which I think happens a lot,
and so everybody's like, well, you know,
this athlete who I really look up to swears
that going off gluten helped, and that might
be completely true, but unless you try it yourself,
you might just be restricting your diet for no reason.
- You know when I think back to when I was
full time cycling, it would take a lot of pressure off,
'cause those decisions that worry about day to day,
like, you know, whether I should eat something
or whether I should go out, you know,
I can go out this evening or am I ready,
like, good to train today.
If there was something to help you make
those decisions you can kind of almost sit
back and be like, okay, well, that's cool.
I can do this, I can do that.
And I think it would've been very useful,
if I'm completely honest.
But it's also annoying to hear you say
that it existed in the 80's and I'm like,
ah, man, I was, you know, I wasn't in the 80's,
I was in like the 2000's, and I still didn't know.
- It wasn't in endurance sports until really quite recently.
The power lifter sort of got it first,
and it was like their little secret for a really long time,
but they noticed that when your HRV was high,
you're one rep max would go up because you
were able to recruit all of your neurons
to fire at the same time.
So a big thing with one rep max is
in those really intense short activities
that it's as much about, like, all of your neurons
pulling on your muscles at the same time
as it is literally like muscles mass
which is why your muscles don't change
that much day to day, but you can lift
different amounts day to day.
And so, they were very interested in the sort of,
direct measure of your autonomic nervous system balance.
- Let's talk sleep, shall we, so,
your personal kind of field of expertise, I guess.
The analytics that Whoop can give you
about sleep is far more detailed
than the length of time you're asleep for.
So, what kind of have you learned,
or do you know already that Whoop can
show you in terms of what type of sleep
you should be after, or how you can improve
your sleep or all those kind of important facts is?
- Yeah, so, I guess for people who don't know,
Whoop will auto-detect the fact that you're asleep
or napping, and then once we detect
that you're asleep, we divide that sleep
into one of four sleep stages.
You're either awake, you're in light sleep,
you're in slow wave sleep which is
the physically restorative part of sleep or REM sleep,
which is the mentally restorative part of sleep.
And we knew for a really long time,
both from sort of literature that pre-dates Whoop,
but also from our own analysis of our data,
that the more slow wave sleep you get,
sort of the higher your HRV's going to be the next day.
The more REM sleep you get, you're going to see
the effect on performance, stuff like that,
but what was really kind of like not well understood
was what you can do in order to affect that.
So we know that our bodies are going to
allocate time within sleep to the stages
that it determines that we need,
provided that you're giving your body the opportunity
to get into those deep stages of sleep.
And so there's a lot of little things you can do,
like the more conducive your environment is to sleep,
the more of those deeper stages you'll get.
So, having your room be dark, quiet, not too warm,
even like good air quality, stuff like that.
One of the things we discovered, I guess two years
ago now, is that one of the most in control
factors that determines how much slow wave
and REM sleep you get is how consistent
your bed time is, and that's really coming
from maintaining a healthy circadian rhythm,
and so, you can give yourself eight hours to sleep
or 10 hours to sleep and if you're doing that
sort of at random times, you're going to get
less good quality sleep than if whatever you're
getting, even if it's slightly less, it is
perfectly consistent night to night,
and so that's like one of the big things
we've been trying to educate our athletes on
for the last year and a half, two years
because it's so completely perfectly in your control.
- Well, my mind is ever so slightly blown after that.
I'll be completely honest, I think back
to when I was a pro cyclist many years ago now,
and I just imagine the confidence
that having this kind of information
at my fingertips would've given me.
I think I tended to err on the side of caution
in terms of training load to having overcooked it
a couple of times earlier on in my career.
I just can't help but think, imagine being able
to know categorically that information.
We'll have a video over on the tech channel
which will actually be filmed in the future,
but going out at the same time as this one,
where we'll go into a bit more detail
about how you use the app and the tech involved
in that specifically.
In the meantime, if you haven't clicked
through to that video, please make sure
you give this one a thumbs up.