Zone 2 vs HIIT: How Athletes Structure Sessions and Avoid Overtraining | Inigo San Milan | Be Well Moments

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Are you getting the balance between Zone 2 and HIIT right? I’m exploring how an 80/20 split by sessions, with most training at lower intensity and select high-intensity work, supports results without burning you out.

This clip explores why all-HIIT programs often feel unsustainable and can lead to fatigue or injuries, what 80/20 really means when you count sessions rather than minutes, and why only about 5 to 10 percent of total minutes across a season tend to be truly high intensity in athletic programs. We discuss how Zone 2 should be harder than easy cruising to drive mitochondrial adaptations, practical ways for busy people to blend mostly Zone 2 with a small dose of intensity toward the end of some sessions, and why complete off days can be more restorative than so-called active recovery. I also share my experience of feeling awful doing fasted HIIT, and we touch on how women may find certain efforts tougher due to muscle fibre differences related to ATP production. As a nutritionist and health communicator, I connect the training plan with recovery needs, including the role of rest for immune health.

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Episode Transcript

(00:00):
Welcome to Live Well Be Well, a show to help high performers
improve their health and well-being.
You're saying that men and womenshouldn't have this really any
differently? We should both be prioritising
zone 2. Yet actually women will struggle
more with hip because of these, because of these muscle fibres

(00:21):
to produce the ATP. And that makes so much sense
because I went through a phase probably about eight years ago
when HIT was, I don't know if you remember, there was a huge
surge in HIT and everybody, every studio was opening and
everyone was doing HIT. And I felt worse than I've ever
felt before, like awful. And also what what was coming up
at that time. And I'd be really interested to

(00:43):
ask you about this with exerciseand also how you train athletes
and if it's different for men and women.
I was also fasting before I was doing those sessions as well.
So you can imagine I had like noenergy in me and I was going off
to do these ridiculously expensive classes for an hour
and raising into zone 4, Zone 5 and I've never felt worse in my
life. Yeah, you're, you're totally

(01:04):
right. And this is one one of the
things that, yeah, I mean, heat was was a hype and, you know, it
was very popular 10 years ago. But you know, very few people
from 10 years ago, they're stilldoing it or not, not that many
people because or at least people who were pursuing health
benefits through heat, you know,it's not sustainable and it can

(01:28):
lead to injuries. Again, I am not saying that heat
is bad for you, but any exerciseprogram based on heat, right,
It's not sustainable. There are no athletes in the
world who who all that training they do is hit.
It doesn't exist. And believe me, I know a little
bit about what athletes train, but it doesn't exist.

(01:51):
And in fact, now, and I'm not saying if it's a tendency or
not, but what we, we have seen it historically is that 8020,
whereas the proportions of, of, of the time or not, not the
time, the sessions, not the time, because that you know that
the sessions that, that you dedicated to different

(02:11):
intensities, about 80% is lower intensity, call it zone 2 maybe,
and about 20% is higher intensity.
This is the approach that we've been using with athletes forever
and it has worked. Any other approach of doing
2080, like 20% lower intensity and 80% hit, it doesn't tend to

(02:33):
work. It causes overtraining, fatigue.
And that was mentioned earlier, but that's kind of what we do
with atheists. So that the whole thing of now
the 8020 it comes from from again like like as many concepts
come from what we have learned with athletes, they're now
becoming mainstream, right? But at 8020 is not about minutes
or percentage of minutes. Because in fact, if we go by the

(02:55):
minutes, it's even less. If you look at that volume, just
observationally, if you look at the volume of any athlete,
whether it's a a very high intensity of athlete like a
swimmer, 100 meter swimmer or a roar or a marathon runner, about
5 to 10% of the entire minutes per season are in high

(03:18):
intensity, right? So, but we need to think more
about sessions. So it's about 80% of the
sessions to contemplate maybe zone 2 and about 20% of the
sessions soon should contemplatehigh intensity.
And the way we break it down is to yes, so, so many times we
isolate a session because they have more time to specifically

(03:42):
to high intensity because of thedemands of competition.
Other sessions specifically is high Zone 2 training and they
can be 4-5 hours, but their models don't have for five hours
or they even can do for five hours at that for zone 2 or high
intensity. So the way it's about to come
combining as I, as I said, but if you do four days a week zone

(04:03):
2IN combination with high intensity, at least 2 or so
towards the end, that's when youstart hitting some sweet spot.
And then that was like the, the,the, the distribution, right?
It's more like 8020. But but again, like, you know,
hit, it's something that, yeah, it's just a lot of people, you

(04:25):
know, did it, but it's just manypeople don't enjoy it, didn't
enjoy it. Have you had to change a lot of
these athletes mindsets on this approach to more an 80% like
lower intensity and the 20% highintensity?
Like have you seen them have some resistance to that because
obviously you've seen insane changes?
I'd love for you to share some of these stories for for our

(04:47):
listeners, but how is the mindset approach when you're
working with with athletes in this sector?
Not much to be honest, because that's been the mentality always
like that. In fact, you know, for, as I
mentioned earlier, right, if youwatch what swimmers do and have
done forever and they continue breaking records, is that you go

(05:08):
to a swimming and you see the world class swimmers, they swim
up and down, up and down. And then eventually, obviously
they do some intensities, right?But it's not the other way
around. So you don't have to convince
them to, hey, you can't do 1000 sprints a day.
It's bad for you to 5 or to 10, right?

(05:30):
Well, they're already, they're already there, right?
In fact, what I had to convince him more is that the zone 2 is a
much harder intensity than just cruising, which was what a lot
of people were doing because that 8020, they didn't know it
by 20, but you know, that's whatthey were doing was like more

(05:50):
aerobic training, long endurancerun or ride.
It was too easy, right? And it was too easy.
It was close to a recovery intensity and that doesn't
stimulate that by energetics of mitochondrial function as much.
So it was about convincing them that they had to go faster.
And if you look at, well, you look at if you talk to some of

(06:12):
the people that I've been working with, the Zone 2,
especially at high, at high level athletes, it's really,
really, really demanding, very demanding.
And until they get used to that,but it's not an easy training at
all for that. We have recovery days.
OK. And what does the recovery days
look like? Nothing.
No, I'm not active recovery. I mean you yeah, you have to do

(06:34):
nothing. It's important to That's what I
figured. I remember when I introduced
also the concepts or off days in, you know, like a long time
ago to to the athletes I was working with, it was a crazy
idea to have an off day or even a recovery week, like a active
recovery, right? But now everybody does an off
day completely and, and at leasta recovering active recovery

(06:58):
day, which is, you know, like a light run with friends to, to,
to grab a coffee, right. Or a light bike ride, you know,
to grab another coffee with friends and come back.
You know, it's something that ismore to me.
Yeah. There's no, there's no
difference between an active recovery day than just do
nothing, right? Because when you do nothing, you

(07:20):
just rest. And we do active recovery days,
maybe more psychological becauseto break down the to break out
of the routine of training hard,because you need to train by
yourself many times in individual sports.
So that day where you're going to have fun and just gather with
some friends, that's your recovery day for a coffee,
right, for example, or a coffee run.

(07:41):
But yeah, you need you need those too.
To make sure you're performing, but also to make sure I get your
immune system and everything youneed recovery for so many
different dimensions. You know your immune system
plays such a big role in in exercise.
Thanks so much for listening to hear the full episode.
There's link in the description.