Dumb Question about Tirz

[UghItsStupidNIHateIT]

I keep reading that people on tirz can lose significant muscle mass, and in order to combat that, they have to eat a lot of protein and lift weights. However, I’m trying to actually get stronger while on tirz.

Here’s the issue I’m having. For whatever reason that makes absolutely no sense to me, my legs are getting stronger. I can do 615 for 10 reps on a 45 degree leg press (up from 400 when I started two months ago). BUT I’m stuck at 10 pounds for bicep curls and have been since I started. I train full body twice a week with weights, do yoga, and run a few times a week. I can see the muscles starting to come through the fat on my legs. Meanwhile, my arms are doing their best ramen noodle impersonation. Is it possible that I’m losing muscle in only my upper body?

I’m 35 y/o 5’4” female.

HW: 240

CW: 210

Been on tirz since 3/9/26.

 

[cheaperseeker]

This is what Dr Google said:

"It is fundamentally harder for women to strengthen their arms than their legs, largely because the upper body has significantly less natural muscle mass and different neurological firing patterns to begin with.

The difference in ease between strengthening upper and lower body limbs comes down to several key factors:

Lower Baseline Strength:

Women generally possess about 60–80% of the lower-body strength of men, but only about 40–60% of their upper-body strength. This means your arms start at a much lower capacity, making initial gains feel steeper.

Daily Use and Leverage:

Your legs are constantly engaged just from walking, standing, and carrying your body weight against gravity. As a result, lower limb muscles naturally hold more endurance and foundational strength. Arm muscles, conversely, are used primarily for lighter, fine-motor tasks.

Muscle Fiber Composition:

Biological factors, including a higher percentage of Type 1 (endurance-based) muscle fibers in the lower body, make it easier to recruit force in the legs compared to the arms.

Upper-Body Muscle Size:

Women naturally carry less muscle tissue in their shoulders, back, chest, and arms. Because there is less surface area and tissue to work with initially, building noticeable strength or 'tone' requires consistent, progressive overload."

 

[cheaperseeker]

Also, not a dumb question.

Most of what we were taught about exercise is based on studies done on men only, so a lot of it doesn't make sense for women.

 

[amosmylove]

Sounds about par for a woman. Can be frustrating, but having a strong lower body is awesome too. I'm impressed with your results!

I've always had a very strong body for a female, including upper body. I'd rep 35lbs for curls, rep bench 140lbs, could do pull ups at 165 lbs etc. That was all in highschool and college as an athlete. But over the last couple years (well, like 10 years ) I've stopped most sports and all working out due to some severe autoimmune disease attacks, and I am much much weaker now. I imagine I will struggle to get back to having an above average upperbody if/ when I attempt to.

All of my friends throughout my sports teams, except a couple in college that were awesome lady freaks, were normal and built muscle in the way you are describing.

My advice is stay consistent with your arm/upper body days to maintain your strength and add in some harder weights even if you can only do a couple reps, then go back to what is more manageable. Don't give up on your upper body, but definitely expect your lower body to be where the bulk of your gains show up.

 

[staffn1]

Lifting heavier does not automatically equal gaining muscle mass, do not confuse the two. That is especially true in a calorie deficit which makes it much harder to gain muscle mass.

 

[Neptide]

I keep reading that people on tirz can lose significant muscle mass, and in order to combat that, they have to eat a lot of protein and lift weights. However, I’m trying to actually get stronger while on tirz.

Here’s the issue I’m having. For whatever reason that makes absolutely no sense to me, my legs are getting stronger. I can do 615 for 10 reps on a 45 degree leg press (up from 400 when I started two months ago). BUT I’m stuck at 10 pounds for bicep curls and have been since I started. I train full body twice a week with weights, do yoga, and run a few times a week. I can see the muscles starting to come through the fat on my legs. Meanwhile, my arms are doing their best ramen noodle impersonation. Is it possible that I’m losing muscle in only my upper body?

I’m 35 y/o 5’4” female.

HW: 240

CW: 210

Been on tirz since 3/9/26.

I hear you. I was in the same predicament It happens . Take Lots of protein, ceatine and good nutrition. Muscles have to be fed in order to grow. What has helped me is NAD+, Lipo-C with B12. Steak eggs, and complex carbs. It’s hard when you aren’t feeling hunger but you have yo make effort. Go heavier with weights if you are not growing. I have to resistance train till failure in order to grow. Don’t give up

 

[Smiter]

Your training protocol must be different when training the smaller muscles of the upper body. You want stronger biceps, do 6 sets of 3 reps, then 2 sets of 5 reps... The first 6 sets at 85% of your one rep max...The last 2 sets at 70% of your 1RM, but do it with explosive concentric movement and slow eccentric phase. Oh yeah at least 4 minutes of rest between sets. Take long, deep, slow breaths during the rest period.

 

[sheilarae74]

It's actually a good question. Back when I was young I could lift 300lbs with my legs but I couldn't even do a 50lb bench press.

 

[Cumulus]

I keep reading that people on tirz can lose significant muscle mass, and in order to combat that, they have to eat a lot of protein and lift weights. However, I’m trying to actually get stronger while on tirz.

Here’s the issue I’m having. For whatever reason that makes absolutely no sense to me, my legs are getting stronger. I can do 615 for 10 reps on a 45 degree leg press (up from 400 when I started two months ago). BUT I’m stuck at 10 pounds for bicep curls and have been since I started. I train full body twice a week with weights, do yoga, and run a few times a week. I can see the muscles starting to come through the fat on my legs. Meanwhile, my arms are doing their best ramen noodle impersonation. Is it possible that I’m losing muscle in only my upper body?

I’m 35 y/o 5’4” female.

HW: 240

CW: 210

Been on tirz since 3/9/26.

Upper body fuggin sucks for me too. I lose faster there, but I have disease there, so my experience is different from yours. What have you tried for increasing gains? Weight by smaller increments, time under tension, reps? Preacher curls for funsies?