Yeah, so if you want a stronger athlete, I think
any time overloading eccentric weight is going
to be awesome. We've shown that that does produce
greater forces. But if you're really looking
to get the most bang for your buck, more weight
across the whole thing is going to be the best.
So doing something where you're doing a maximal
or super maximal accentuated eccentric loaded
back squat and then staying up with heavier weights.
So 70 % or 80 % concentrically would be the best
to get maximal strength benefits. All right,
Brooklyn, it's my pleasure to have you on Evidence
Strong Show. If you could briefly introduce yourself,
that would be great. Thank you. My name is Brooklyn
Campbell. I am a strength coach at University
of Houston. I currently work with women's soccer
and women's softball. My background in research
was done during my undergrad, which is where
I did the research for my study we're going to
talk about today at Carroll University. And my
co -authors are all from sort of Carroll University
as well. All right. So today we talk squats,
back squats. Specifically, and we will look at
some biomechanics. So, but I will let you to
introduce the study. So what was the aim of that
study? What you were trying to do? So the study
was a comparison of breaking and propulsion phases
of accentuated eccentric loaded back squats and
resistance trained women. And I'll break down
what that is. So breaking and propulsion characteristics
are the lowering phase of a squat and then the
concentric or propulsion phase of a squat where
you're lifting back up as well. So we're looking
at... Both of those with the force characteristics
and the velocity characteristics that go into
that. Accentuated eccentric loaded back squats.
That's kind of a loaded word. And what that is,
is it's a back squat that basically has three
criteria. It has to involve both the lowering
and the raising phase. So the eccentric and concentric
phase of a back squat. It has to be basically
unbroken without minimal destruction. So if you're
doing a back squat, you're not pausing at the
bottom or doing anything different. a different
type of movement or bending forward to cause
weight to fall off or anything like that. And
then the other thing that makes it an accentuated,
eccentric loaded back squat is it has to have
a heavier load on the way down than it would
when you rise back up. So overloading the lowering
portion of the back squat. So practically, it's
this back squat where on the hooks, you have
kind of weight attached. You have this weight
on the way down. As soon as the weight touches
the ground, it's disattached. itself from the
barbell and a portion of the squat where you
go up is without this additional weight. Yes,
exactly. Hooks fall off right at the bottom of
your squat. The squat looks exactly the same
as it would without the hooks. Awesome. All right.
Who did you test and how the testing went? So
testing that we did was performed on resistance
trained women. That's kind of the unique part
of this study. There are other studies that have
been published with the same group of authors
and different leading authors on resistance trained
men as well. But I specifically in my study that
I like was the lead author on looked at resistance
trained women, which is a very understudied group.
And so we had 14 female athletes performing the
test. They were all about college age and their
maximal back squat one RM varied between 1 .1
times their body weight to 1 .7 times their body
weight. So pretty big range in strengths. They
had been training with the back squat for over
a year and resistance training for over a year.
So it was nothing new to them prior to performing
the test. What we did for our testing sessions.
we had four testing sessions the first one when
we got the participants we did an informed consent
and took their height weight and performed a
one rep max test following a standardized protocol
and standardized dynamic warm -up following that
we did a familiarization phase with the weight
releasers so those are those hooks that are falling
off during the familiarization phase we did a
couple different weights first just we were trying
to figure out when exactly is the bottom of their
squat the lowest spot when their thighs are at
parallel to the ground because that's when the
hooks need to fall off so we did a first with
just no weight on the bar figuring out where
the weight releasers fall off and then we did
50 % on the barbell nothing on the weight releasers
again figuring out and then we did 50 % on the
barbell 10 % on each of the weight releasers
so total 70 % performing three repetitions of
the back squat where the weight releasers fall
off on the very lowest point of their back squat
just familiar I sound like that so the releasers
fall off on the first rep and then the second
and the third rep is just carry on without the
additional weight is it yep so in our study we
did a first rep weight releasers fall off you
do two additional sets without the use of weight
releasers the reason we chose to do that is because
there is some studies that show a potentiation
effect on the following repetitions following
the first one so we didn't feel the need to re
-hook the weight releasers after each one because
you're curious what that looked like and then
the potentiation effect would come off on the
fourth and fifth reps and that study was done
I believe on resistance trained males in the
bench press so then back to the study following
sessions that we did there were three other sessions
those were testing sessions they were done on
a random order um it was a traditional session
ael maximal session and then ael super maximal
session so the sessions followed a they'd come
in they do their standardized warm -up um and
they would do three repetitions of a concentric
weight of 50 60 70 and 80 three reps at each
of those during that they'd have a we'd have
a velocity transducer hooked onto the barbell
they'd be on force plates for all of their reps
um they'd have a three minute rest in between
three to five minutes and then So that would
be like the traditional, right? Just basic back
squats. So we had something to compare it to.
And then the AEL maximal was 100 % of their max
on the way down, standing up with 50%, 60%, 70%,
and 80%. And then super maximal, we did at 110
% on the way down, standing up with those same
weights. Ooh, that sounds spicy. It was intense.
It's very hard. It's deceptive because you'd
think like there's a lot of research saying you
can get up to 150 % of your... one rep max eccentrically
so lowering but I'll tell you 110 is pretty hard
I wouldn't want to do much more does it feel
like you're fighting for your life on the way
down with the first one and then you're like
oh my god so happy it went off yeah it definitely
like when you're going down with the 110 when
the weight releasers fall off you spring off
you're like oh my gosh like that was easy you
kind of have to be prepared for it you can't
just depth drop into it or you'll keep going
down you're really fighting for your life with
the heavier weights but a lot of it is it's interesting
because a lot of it is like just familiarized
yourself with it and trusting your body to do
the movement mechanics that you've always learned
with a back squat like don't do anything weird
don't quarter wrap it like make sure you're hitting
your depth slow and steady control the weight
and you've got it how long does it take for an
average person to to learn how to do these squats
it really doesn't take long i mean we did one
familiarization phase which was really only two
or three times using the right releasers then
they came in and if they were doing ael super
maximal they were doing it on their first testing
session so none of our participants or at least
not that I know of, were previously training
with AEL. So it was a pretty quick learning process.
You just have to trust yourself, do your regular
squat. That was the number one thing we said
is like, do your regular squat. Like change nothing
about how you move in your regular squat. And
I mean, it's interesting feeling the weight.
You'll feel them sway a little bit. We had people
to help study the weight so that they weren't
swaying back and forth before we got the squat.
But it's just your basic squat. Really fast learning
process. Could we go through what you have measured?
We measured... the braking mean force, braking
duration, braking impulse, as well as the propulsion
mean force, propulsion duration, and propulsion
impulse. And then we also measured the mean barbell
velocity and the peak barbell velocity during
the effect. Excellent. I think most of these
terms people can comprehend, but could you explain
an impulse? An impulse is sort of a combination
of the duration and the force metrics. How so?
It's the multiplication of them both. So the
impulse is... I guess then combined. Okay. All
right. So we know what you measure of now we
are ready for the results. Yeah. So the results
of the tests were that greater breaking knee
force and greater impulses occurred across all
AEL conditions. So across all accentuated eccentric
loaded back squat conditions. So the super maximal
and maximal accentuated eccentric loaded back
squats produced greater force and impulses. There
was not practically significant differences.
between our barbell propulsion variables and
we didn't notice in our study specifically anything
that displayed we didn't notice any potentiation
effects within our sets and that could be the
population we are testing on that could be our
relative strengths but we did not see any potentiation
effects in our population and that was similar
to the findings on the male participant though
there have been other studies that show male
participants having potentiation effects and
then A unique thing to think about when training
with accentuated eccentric loaded back squats
is the spread that you're giving the athlete.
So if you're lowering 110 % of your max and standing
up with 80 % of your max, you're going to produce
a lot more force. Whereas a larger spread, so
when you're lowering 110 % of your max and standing
up with 50 % of your max, you're going to produce
a lot more rapid force development characteristics.
So just more speed going up. So kind of prescribing
them, you can use... that to decide, well, what
am I trying to do? Am I trying to get maximal
strength? Do I want to shorten the spread? Or
am I trying to produce rapid force development
characteristics? Do I want to make the spread
bigger? All right, let's unpack a little bit.
So if my goal as a coach is to produce more force,
so I want the athlete to get stronger, how would
I apply the findings of your study? Yeah, so
if you want a stronger athlete, I think any time
overloading the eccentric rate is going to be
awesome. We've shown that that does produce greater
forces. But if you're really looking to get the
most bang for your buck, more weight across the
whole thing is going to be the best. So doing
something where you're doing a maximal or super
maximal accentuated eccentric loaded back squat
and then staying up with heavier weights. So
70 % or 80 % concentrically would be the best
to get maximal strength benefits. Okay. And then
if I want the athlete to produce force faster,
so be quicker potentially? Yes. So to produce
force faster, you would want to have larger spread
with your accentuated eccentric loaded. back
squats between the eccentric and concentric phase.
So that would look like something maybe where
you're doing 110 % total weight going down and
then coming up with something like 50 % or 60%.
Or you could even just do a maximal repetition
where you're having 100 % on the way down 50
or 60 % on the way up. Do you have any other
tips for coaches if they would like to try and
apply it? Yeah, some tips I would have is be
thoughtful with how you use it. Anytime you're
using AEL, you want to think about the load,
you want to think about the frequency. And then
even like the duration of how you're doing it.
Accentuated eccentric loaded back squats are
a great tool because they can be prescribed for
hypertrophy training, strength training, or power
training. It all goes down to how you prescribe
it. So if you're wanting to use it, maybe you're
just doing it during peak week and they're not
doing accentuated eccentric loaded back squats
throughout the rest of the week. Or maybe they're
doing it throughout the whole training phase.
It's really important to just think about how
you're implementing this and what adaptation
you want to see because that can... change how
you use the weight releasers so would you use
them for potentiation mainly and then whatever
the outcome of the exercise should be then the
loading will be applicable to the outcome you
you desire yeah so depending on what outcome
you're hoping to get i would i would say it would
change i personally would use it more in a maximal
strength phase just given our findings i think
it really supported that if i were planning to
use accentuated eccentric loaded backshot with
my athlete I would make sure it is athletes that
are really great lifters. I don't think this
is something for the novice athlete. It's very
advanced. It's a hard training technique. So
finding an athlete who's almost stagnant in their
training and trying to use this to take them
over the edge to try something new, it's a novice
stimulus for most. So using it in that situation,
I would probably put it then. All right. So let's
sum up. How, in maybe three sentences, would
you use this type of training? I would use this
training with my stronger athletes during the
strength. phase and I personally like using it
just during a peak week so maybe on my fourth
week or third week of the block doing a sort
of an overtraining sort of stimulus and then
not using it on a deload and taking it away that's
how I like to use it awesome do you use this
technique with your athlete personally your athletes
I do I currently have a lot of younger athletes
so I haven't used it this year much but last
year I had a large group of graduate students
and seniors who had really strong um strength
and conditioning backgrounds and had back squatted
for years and I pulled a number of them to do
um to do eccentric eccentric loaded back squats
with and they thought it was the most fun and
something that they were like really felt that
they were getting a great benefit out of it's
a unique thing it brought excitement back into
the weight room so it was really cool that's
awesome that's that's a good enough reason I
think if you have athletes who are training very
hard preparing for competition many of the coaches
in the audience are olympic weightlifting coaches
so you know Olympic weightlifting two exercises
and then you have front squat and back squat
to support it. Maybe some deadlifts, maybe some
pulls. Yeah, there's, I don't know, 35 exercises
to choose from. So at some point it's all the
same every day. So if you can add a bit of spiciness
and it is a challenge too. I have never done
these, but you can imagine that going down with
110 of your max back squat is exciting mentally
and everyone is watching and you need some...
help to attach the hooks first and for them to
not, you know, not be swinging and so on. So
it is a fun way to make athletes work hard. Yeah,
it's exciting. We have quite a few sets of hooks,
but nonetheless, I still am safety's top priority.
I always have one athlete spotting from behind,
two on the sides, making sure the releasers come
off, stabilizing the weights and just those three
athletes helping out the one doing the back squat
alone just involves so much excitement and teammates
hyping. up each other so it's really awesome
that's amazing all right coaches use it absolutely
put it in try it out try it out for yourself
first and then try it out with your athletes
awesome well we have two questions to finish
short questions the first one is what is your
favorite lift so I saw that you were going to
ask this one and I went back and forth on what
I should say but my favorite lift is the front
squat I really do like front squatting I like
the core engagement I feel like I always feel
it when I front squat I know I've done something
when I front squat It's my favorite. I know most
people hate front squats. So whenever I say that,
I'm like, oh, they're going to eat this one.
But it's just, it hurts, you know, you feel like
you've had some good working. Awesome. Hard worker.
All right. Last question, where people can find
you if they want to follow your work or ask a
question or just see what you're doing with your
athletes or with your research. I'm always available
for email. So my email is B -A -C -A -M -P -B
-2 at central .uh .edu. And as well as... Instagram
DMs are perfectly open. My Instagram is Brooke988
and that's E -R -O -L -K -E -9 -8 -8. Excellent.
Brooke, thank you so much for today. It was a
pleasure. Thank you so much. I appreciate it.