---
title: 'I Transformed My Wife''s Body In 90 Days'
source: 'https://youtube.com/watch?v=0xHAC2vKgbM'
video_id: '0xHAC2vKgbM'
date: 2026-06-28
duration_sec: 1285
---

# I Transformed My Wife's Body In 90 Days

> Source: [I Transformed My Wife's Body In 90 Days](https://youtube.com/watch?v=0xHAC2vKgbM)

## Summary

A couple embarks on a 90-day glute-building challenge. The wife, who injured her back doing heavy squats, trains with low-back-friendly exercises from glute expert Brett Contreras, while the husband uses conventional heavy lifts. The goal is to see who can grow their glutes the most, with the loser going vegan for 30 days.

### Key Points

- **Challenge Setup** [0:00] — The husband and wife begin a 90-day glute growth competition. The wife will train without squats, deadlifts, or heavy spinal loading due to a past back injury; the husband uses any exercises. If the wife wins, the husband goes vegan for 30 days.
- **Glute Expert Introduces Four Movement Patterns** [1:16] — Brett Contreras recommends four movement patterns for well-rounded glutes: lower body press, lower body hinge, squeeze, and abduction.
- **Squeeze Exercise: Hip Thrust** [3:01] — Brett invented the barbell hip thrust. He emphasizes avoiding spinal hyperextension at the top of the movement to prevent back pain, and suggests a 'scoop method' (tucking chin, moving from chest down, tilting pelvis upward).
- **Abduction for Upper and Lower Glutes** [3:58] — Brett calls hip abduction 'penalty-free volume.' Sitting upright targets upper glutes; leaning forward targets lower glutes. Pairing both sets can finish a workout effectively.
- **Soreness Not Indicator of Growth** [6:21] — Multiple studies show soreness does not indicate muscle growth. Brett's chosen exercises cause less soreness and muscle damage, aiding faster recovery.
- **Heavy Squats and Testosterone Spike** [6:38] — Heavy squats provide a 10–20% testosterone spike that lasts only 15–45 minutes post-workout. This provides no long-term hormonal advantage.
- **Squats vs. Hip Thrust for Glute Growth** [9:21] — A 2023 study by Brett found squats and hip thrusts are equally effective for glute growth, though squats grow quads and inner thighs more.
- **Women's Recovery and Volume Advantages** [10:50] — Brett observes that women recover faster from lower body workouts, allowing more volume and frequency. The wife dedicates ~80% of training to glutes, while the husband splits volume across multiple muscle groups.
- **Vegan vs. Meat Eater Muscle Building** [13:15] — A study comparing vegans and meat eaters consuming 0.7g protein per pound body weight found both groups built the same muscle and strength after 12 weeks, showing protein source is less important than total protein intake.
- **Bar Test and Injury Setback** [14:16] — A spontaneous 'bar test' (trying to stop a falling barbell) fails. The wife later experiences back tightness, forcing a pause. The challenge resumes after rest, but training frequency is dialed back to two days per week.
- **Vertical Jump Improvement** [18:46] — The husband's vertical jump increased by 5 cm (from barely average to high above average) and broad jump by 2 cm, attributed to glute training.
- **Final Results: Wife Wins** [19:19] — After 90 days, the wife grew 2 cm in glute circumference (92cm to 94cm), the husband grew 1.5 cm (92.5cm to 94cm). The wife wins, and the husband must go vegan for 30 days.

### Conclusion

The challenge demonstrates that glute growth is achievable without heavy squats or deadlifts, using targeted, low-back-friendly exercises. The wife's victory highlights the importance of consistent, high-volume training and proper technique over maximal loads.

## Transcript

We both have no butts.
>> That's my wife. She's trained with one
of the most jacked personal trainers for
10 years. From the outside, her life
looked perfect. But there was one thing
stopping her from being truly happy. 5
years ago, she hurt her back badly doing
heavy squats. And ever since then, her
butt got flat.
Sorry.
Flatter than she'd like. But she's not
alone. I've gone from cake to pancake
because I not only sit more than I used
to, but I also find glute training
extremely uncomfortable. So, I got lazy
with it. But strong glutes don't just
make your butt look better in clothes.
They help you move better, lift
stronger, and can even help with back
tightness and knee pain. So, for the
next 90 days, we're on a mission to
build our glutes. She'll build hers with
no squats, no deadlifts, and no heavy
loading on her spine, whereas I'm free
to use whatever I want. And if my
injured wife outgrows me, I go vegan for
30 days.
>> Without crazy heavy weights, without
squats, without deadlifts, can she still
grow her glutes?
>> Yeah, this is a piece of cake. I know it
sounds impossible to you because you
built your glutes with heavy squats and
deads.
>> That's Brett Contras, the man who
literally invented the hip thrust and
has dedicated his life to studying and
growing glutes.
>> So, first exercise we're going to try is
the glute dominant step up. Okay, I want
you leaning forward a little more and
reach back right there. Tap. Come back
up. To build well-rounded glutes, Brett
recommends doing four movement patterns.
A lower body press, a lower body hinge,
a squeeze, and abduction. He's used a
simple approach to transform even the
flattest of butts. But because of Tonnie
sensitive back, we do have to find
workarounds for the heavy barbell
exercises Brett would normally use.
Starting with a lower body press, where
most people would simply squat.
>> This looks like a squat. This looks like
a glute dominant squat, a box squat with
mostly vertical shins. So, you're
training the glutes as if you were doing
a squat. Anyway, so now that we see that
body weight was tolerated well, we have
a 15lb dumbbell, so about a 7 kg
dumbbell. It's a little harder now.
>> Yeah.
>> Yes. This is great. What I want is shin
mostly vertical, thigh parallel. This
creates the most requisite hip extension
torque being furthest out. So, she's
getting the stretch. She's getting the
torque loading. And then this foot maybe
a little back right there.
>> But now we needed a safer hinge movement
instead of traditional deadlifts. This
is a single leg dumbbell deadlift, which
challenges the glutes as much as normal
deadlifts, but requires much less
weight. But Brett emphasized the key to
activating the glutes rather than the
hamstrings is to keep that knee slightly
bent.
>> Yes. Come up. Don't even straighten it
out. Yep. Oh, that's
>> Yes. Right there. Just like that.
Perfect.
>> Okay. So, I'm not coming like full
stand.
>> Yep. Exactly.
>> How's it feel, Bab?
>> I feel it.
>> Another one. Another one.
>> I'm so weak.
>> So far, we're two for two as we moved
into our third type of exercise, the
squeeze, which in this case happens to
be the exercise Brett actually invented,
the barbell hip thrust.
>> All right, so already I'm thinking, all
right, feet back a little. You want the
knee at around a 90° angle. Crawl up a
little higher on this bench right there.
Okay. Now, bust out a couple reps. Let
me see your natural form. I'm watching
to see if she naturally has a tendency
to hyper extend the spine. She doesn't.
So, you might be okay doing regular hip
thrust. What Brett's watching for as she
reaches the top of each rep is whether
she's overextending her hips and
creating pressure in her lower back,
which is the most common cause of back
pain when performing this exercise. To
avoid this, Brett recommends trying the
scoop method where you tuck your chin
down and move from the chest down,
tilting your pelvis upwards by squeezing
your glutes. Now, you won't be able to
get as high, but that's a point.
>> Eight. Great form. Good lockouts. Yes.
Okay.
>> And with Tonnie already lifting heavier
than she has in years, we just needed
one more exercise to round out her
training. A hip abduction movement.
>> I always call this penalty-free volume.
You add it in, it doesn't beat you up.
adds to the glute hypertrophy stimulus
without fatiguing you much. We're going
to put these pads right here so that you
get more active range of motion. Now you
can hold on the handles. Let's see how
this feels. Tap. Make sure you come in
and tap.
>> For this exercise, you first target your
upper glutes while sitting upright. But
if you lean forward at the end of your
set, you then switch tension to your
lower glutes. So by pairing both sets
back to back, you can target multiple
areas of your glutes to finish off your
workout. General rule of thumb, if you
have low back pain, if it feels off, if
you feel anything during the movement
itself, don't do it. Skip it.
>> With the trip to Brett being a success,
here is the workout plan Ton is going to
now be using, training her glutes twice
per week and tracking it all in our
Built with Science Plus app. As for me,
while I will be stealing some of these
exercises, I'll still be doing heavy
compound exercises like squats and
deadlifts. So, we'll be able to see if
that gives me a huge advantage or not
after the 90 days of training. On day
one, Tony's glute circumference comes in
at 92 cm, while mine is just slightly
bigger at 92.5. But while most people
think glutes are just about making
people turn their heads, your glutes are
actually one of the biggest drivers of
power, speed, and force production. The
most explosive athletes almost always
have incredibly powerful glutes. And
then there's mine.
>> Watch out. Watch out. WATCH OUT. WATCH
OUT.
OKAY. SO, I also want to see if by
training my glutes more seriously, it'll
lead to any improvement in how high and
how far I can jump without actually
practicing it, which on day one is
coming in at
the winner, right? 51.9.
>> Oh,
okay.
>> Wow. Look how far I can jump.
>> And with our baselines recorded, it's
time to start training.
Whenever I get close to failure, I get
really angry and really mean. Ow. Ow. I
hate this one.
>> Week one was rough. For the past 6
months, I've honestly just been lazy
with my glutes training and so they're
struggling to keep up. As for Tonnie,
>> I'm a little concerned because I've just
finished my first few workouts and my
glutes aren't really sore and to me
soreness means growth and development.
So, I don't know what that's about.
>> But multiple studies have actually shown
that soreness is not an indicator of
growth, which is actually why Brett
chose some of these exercises. He's
found that they don't lead to nearly as
much soreness or muscle damage as
squats, deadlifts, or Bulgarians do,
helping Tony recover faster and feel
less beat up. However, one proposed
advantage of heavy squats is they boost
your testosterone levels. Sounds like a
serious advantage, right? Well, there is
some truth to this. Heavy squats do
actually provide a 10 to 20% spike in
testosterone. And the boost we see with
squats is higher than it is with other
leg exercises like leg press. However,
this boost only lasts about 15 to 45
minutes after a workout before returning
to baseline. So, while it might explain
why heavy squats make me feel like an
absolute beast, it's not going to
provide me with any hormonal advantage
over Tawni. But speaking of hormones, I
am noticing a big spike in dopamine as
it's the first time in years that Tonnie
and I have trained together. Although
she says all my enthusiasm can be a bit
much.
>> You don't want a hug?
>> No. Get away from me.
>> Which makes it difficult when I offer
coaching or push her to train harder.
>> Implementing my last set where I did 13
reps and I would say I did max effort.
Like that was my max.
>> I have to tread very carefully. We could
put it as max. You did push hard that
>> I did. So I pushed to my max. But so
far, things weren't going quite as
smoothly as we expected. Despite doing
every exercise correctly, Tonyie was
very scared of pushing harder, just in
the fear of hurting her back. Again,
>> my left leg, like my glute, it feels
like it's cramping, but also my left
side is where I have an issue with my SI
and parapformis. So, it's hard for me to
decipher if I'm having a glute cramp or
if I've slightly hurt myself. And on top
of that, she was struggling to eat
enough. Not because she wasn't hungry,
but because she was scared of gaining
fat.
>> If I'm laying it all out on the table
here, I'm on my period. Whenever I'm on
my period, I always gain a few pounds.
Usually like 2 to 3 lb. Like I can see
the water weight. It sits in my stomach.
It sits like heavier in my face. So, the
thought of having to put weight on isn't
a pleasant thought for me. As for me, my
glutes were finally getting used to the
new volume and actually started boosting
my squats, making them feel smoother and
much stronger. So, today I got squats on
the menu. And one thing that I'm
actually doing is just a very subtle
tweak with my form to emphasize the
glutes a little bit more. And you guys
can try this, too. One way of performing
the squat is a bit more quad dominant.
And so, your back is upright and you let
the knees drive forward. But what I'm
doing is since I want to focus on the
glutes a little bit more, I'm actually
going to focus on keeping my shins more
vertical and pushing my hips back,
leaning forward a little bit. All it
does is it shifts the emphasis a little
bit from the quads, more so to the
glutes. And hopefully that gives me a
little bit more of an edge to help win
this challenge. And while you might be
thinking squats are giving me a huge
advantage over Tawni, back in 2023,
Brett actually ran a study comparing
squats against hip thrust. And while
squats did grow the quads and inner
thighs more, for glutes growth, they
were both equal. And based on Tony's
progress so far, it honestly seems like
I'm the one that was starting to lag
behind.
>> I'm telling you, the glutes are popping.
Holy.
>> I don't see it, so I don't know.
>> What do you mean you don't see it? The
camera definitely sees it. Look at this.
>> By week three, Tonnie was sending mad
PRs, and the gains were clearly coming
in.
>> Bab, you just did 135 lbs. That's a
plate. You said
>> I know. I'm really proud to be honest
cuz I haven't done this weight in like 6
years. My girls are proud of me too. And
it actually felt really easy. Like that
was 12 reps.
>> However, Tonnie is not the only one
getting the cake.
>> Week three.
Wo wo wo. Dennis, you see that?
>> Wow. If this is week three, can you
imagine what week 10 is going to be
like? Go.
I recently watched Heated Rivalry where
the actor's glutes blew up online,
showing the world just how much ladies
appreciate a strong butt.
>> How important would you say glutes are
on a guy?
>> I like athletic glutes on a guy. I don't
want like a big booty, but I want you to
have like
>> glutes. Yeah.
>> Okay.
>> Like we don't want a guy that can just
do like bicep curls and go do a squat.
>> Now, technically, Tony actually has two
big advantages over me. First, based on
Brett's experience, he's noticed that
women seem to recover faster from lower
body workouts than men do and can train
their glutes with more volume and
frequency. And while the heavy weights
I'm using may be a factor, I am noticing
that by the time Tonnie is ready to go
for her next workout, I still need
another day or two to recover, and I
just can't keep up with how many sets
she's been doing. But second, and this
is the biggest factor, about 80% of
Tony's training right now is dedicated
purely to glutes. Meanwhile, I'm still
doing a lot of volume for my quads and
my upper body. And although this has yet
to be actually studied, when I wanted to
grow my shoulders in the past, I scaled
back everything else and poured more
volume into my shoulders, and it led to
the fastest growth I've ever seen.
Because when your body has fewer
competing priorities, it can move more
resources towards one area. So, if that
same principle applies here, Tonnie
should be able to outgrow my glutes,
which is concerning because I love my
meat. And if she wins, I'm going vegan
for 30 days. Let's see what measuring
tape says. 30 days, your booty is up
exactly 1 cm.
>> Oh,
>> was that good?
>> That's very good.
>> And now it's my turn to measure my
glutes after 30 days. The result was not
what I was expecting. Come on. What are
we at?
>> 93.5.
>> No way. Okay. My glutes have also grown
1 cm.
We are tied. But I may start out growing
her because based on her tracking in our
Bit Science Plus app, she wasn't
reaching her target calorie intake. If
that continued, her progress might
eventually stall. So to motivate her, I
decided to do something I honestly
hadn't done for her in years. I cooked
for her. We'll see what she thinks in
just a sec. But Tanya and I actually met
about 10 years ago at the gym. But as my
work got busier and with her back
injury, we started spending less and
less time together. So, my hope is this
experiment gives us more to do together
and rebuild more than just our bodies.
Hopefully, I didn't ruin all my chances
by butchering this food.
>> Oh my god.
>> Oh my god. You actually like it?
>> Mhm.
>> Oh,
>> it's really good.
>> Like a restaurant.
>> Really?
>> Mhm. I'm so happy.
>> It's the first time in a while that we
actually sat down at home and enjoyed a
meal together. Now, some of you might be
thinking Tonyie has a huge disadvantage
with her diet, that you need to live off
chicken breast to build muscle. And I
used to think that, too. But the latest
research is making me rethink that. A
new study took two groups of lifters,
vegans and meat eaters, and had them
both eat 0.7 g of protein per body
weight per day. Now, the vegans ate a
variety of protein sources like tofu,
soy, and lentils. Whereas the meat
eaters obviously relied on meat, protein
shakes, and eggs. Now, you'd expect the
meateers to have at least a small
advantage, but after 12 weeks, both
groups ended up building the same amount
of muscle and strength. So, as long as
you're getting enough protein, it
doesn't seem to matter too much where
that protein is coming from, which
honestly makes me slightly less
terrified of going vegan for 30 days.
But, I still really do not want to give
up my favorite foods. And even though
we're only 30 days in, I do want to see
if we can pass the bar test.
I can't even feel it.
>> Your back stopped it.
>> Unfortunately, we both couldn't stop the
bar. But if you watch closely, I kind of
did manage to stop it a little bit. And
that is when Tonnie decided to take her
glute training to the next level. So
far, Tony's been doing around 20 sets of
glutes per week and seeing some pretty
good progress. Holy.
Wow, that's crazy.
>> But for Brett's clients that wants the
most growth possible, he takes this all
the way up to 30 to 40 sets per week.
That extra volume seems to speed up
their growth. And so for Tony, this
spends ramping up her glute training
from two to 3 days per week.
>> And that makes me really nervous because
I'm not going to lie, with my back
injury. So it's just like a fear thing
for me. And I really really hope that I
don't hurt myself, hurt my back because
I really want to reach my glute goals. I
don't want to let Jeremy down. I don't
want to like get frustrated and let
myself down.
>> Now, at first everything felt fine, but
slowly tightness started building up in
her upper left glute and then into her
lower back and eventually this happened.
And so we decided to put the challenge
on pause for a few days. H. So, I hurt
my back at the gym yesterday and I came
today to try to work out and it's very
clear that I'm going to need a few days
off, which is really frustrating for me.
>> Connie is at work right now, but she
just sent me a text and uh just saying
how she's not feeling too well. She's a
bit sad and I think what's going on is
that this challenge is putting a lot of
pressure on her. I think like she not
only wants to win obviously, but she
just doesn't want to let you guys down.
After a few days of rest, thankfully her
back started feeling better.
>> I feel so good.
>> Do you want to go back on the challenge?
Totally fine if you want to drop out. No
hard feelings.
>> Are you scared you're going to lose?
>> No, I'm trying to be nice. Okay, but
fine. I'll take that as a sign as you
are ready to go back and I'm just going
to say I'm not going easy on you. Okay.
>> Okay.
>> All right.
>> I want you spicy, too.
>> All right. Let's go. But after just a
week off of training, Tony's glutes felt
and looked a bit flatter than usual. And
she started worrying she was losing
muscle. And she wasn't just imagining
it. When you stop training for a week or
two, your muscles store less glycogen.
And since glycogen pulls water into your
muscles, they'll look less full. It's
kind of like letting air out of a
balloon. But while your muscles might
look flatter and your strength might
also dip because you just haven't
practiced your exercises, most research
suggests it takes at least 3 weeks or
more of no training to start losing
actual muscle. That said, we definitely
do not want her to hurt her back again.
So, even though we might see a bit more
growth training her glutes three times a
week, it was a no-brainer to dial her
training back to just two. And to help
keep her consistent, we even found some
creative ways to do her workouts at
home, which we've even added to our Bit
with Science Plus app. That way, our
members don't need to always rely on the
gym to make progress. And with only a
few weeks left, Tony's glutes were
making the fastest progress ever. And if
I'm going to be honest, even if I lose
and have to go vegan, this challenge
really is a win-win for me. While Tony's
glutes were blowing up, all of my glute
training was actually leading to some
unexpected benefits.
today. That felt more like a jog. My
treadmill can't even go any faster, but
definitely feels like my glutes are
contributing more to the run. Like, it's
helping me with my run. And all these
benefits weren't from actually changing
much to my leg workouts. I mainly just
started doing hip thrust again and
experimented with some of Brett's
exercises, which helped my other
exercises feel stronger, and more
importantly, just help my body move and
feel a lot better than it used to. So,
if you've been neglecting your glutes
like I was, just start by adding three
hard sets of hip thrust to your leg
days. But with one week before our final
results, we decided to take a trip to
Hawaii to show off our glucans. Holy
moly.
What the heck do we have here? And on
the final day of the experiment, she
didn't just bring the heat to the beach.
She broke another PR. First time ever,
two plates on the hip thrust.
>> I am finally done my glute video with
Jeremy. I am so grateful that Brett
Ferris let us come into his home. He
showed me a bunch of lower back friendly
glute exercises and I'm forever grateful
for him for that because doing this
challenge just showed me that I am
capable and there are ways of getting a
booty. As for me, I've got one more
final test. After 90 days, did these
glute gains actually improve my jump
performance?
So, that is pretty much a 5 cm increase,
which is pretty impressive. I wasn't
sure if my glute strength growth would
impact vertical jump at all. But that
honestly motivates me even more than
just the growth is seeing the athletic
performance there cuz I love playing
sports too. So my vertical jump went
from just beating average to now being
on the high end of above average. Though
still not enough for my Asian mom to be
proud, but broad jump scored excellent
on day one and I still managed to
increase it by 2 cm.
>> Not bad. Not bad. But now it's time to
measure the glutes and see who actually
grew them the most in the past 90 days.
Final day is here. I am extremely
nervous, especially after seeing what
I'm what I'm up against today.
I'm done.
There's no way.
So, you started at 92 cm and today you
are at 94 cm.
2 cm of growth. Good job, Evie. Good I
won a 95 now. Did I win?
>> Please, God. There's no way.
>> That's where you are.
>> Yeah.
>> There's no way.
>> You can't.
>> All right. Do it again.
>> You can't eat them.
>> You're right here. All right, guys. We
have measured and I am what?
>> Plus two,
>> which means
>> I am plus 1.5.
>> Which means
>> which means I'm I'm cooked. You won. You
won. You won. You won. I also won. I
also won. But it wasn't until I tried on
my wife's shorts that I truly
appreciated my new glute gains. So,
while this does mean I have to go
meatless for 30 days, at least this
gives Tonnie and I a chance to enjoy
more dinners together. Oh, and she's got
some serious cake that I could stare at
all day. So, still feels like a win for
me. I'm honestly just so proud of
Tonnie. She's overcome like some of her
biggest fears and she's genuinely
enjoying the gym again. and she did all
of this without lifting crazy heavy. I
think it goes to show you that there's
no musdo exercises. What matters the
most is good form and choosing exercises
that actually fit your body and feel
good. And that is actually why we
created the Build with Science Plus app.
Both mine and Tony's workouts are in
there, but the program adjusts based on
how your specific body responds to your
plan. So, you're not just copying
somebody else. And if you want to try
it, you can test it out completely free
for 2 weeks. Just scan the QR code here
or head to builtwithwithscience.com. And
if you guys want to simplify your glute
training and focus on the only two
exercises you actually need to fix your
flat butt, give this video a watch next,
which we recorded with Brett. Thank you
so much for watching.