Do Weights Make Women Bulky?

Will Weights Make Women Bulky?

Dave Thomas San Diego Performance360By Dave Thomas
Owner, Performance360


“I don’t do strength training because I don’t want to get bulky. I just want to tone.”

I could do 10 minutes of sprints and not want to puke more than I do when I hear girls utter that phrase.

I would prefer to have someone waft salt crystals into my retina than continue to have women be scared of heavy weight training.

I would rather watch a lit candle burn start to finish than to have to discuss “toning” ever again.

I am not sure whomever first coined and promoted the term toning. Scholars maintain that Gwyneth Paltrow is to blame, but we’ll address toning and all of its horror in a little.

As a gym owner and coach, I will be dealing with this preconception for as long as I coach for a living, and I am firmly aware that this notion will sit in the back of hesitant women in the world of weight training.

I utterly loathe this topic of conversation for three main reasons.

Number one, the whole notion of trying to shape women into a single body type irks me deeply. I am not here to define what a woman should look like one way or the other. I am a man and I am well aware many women think it’s out of my lane to be writing about something like this. I can’t control that. I can only share what I know from a physiological perspective and helping hundreds of women get amazing results. Be thin, be muscular, be athletic, be flabby. Whatever makes you happy. That’s your call on how much muscle you want to have for your goals. I’m simply here to promote strength training to those afraid to perform it because of perceived negative biological adaptations.

Number two, I am a personal advocate of women adding muscle and ditching the notion they must look like Giselle (she deadlifts, by the way). I think muscle looks great on women. It’s fuckin’ hot. As a man with a penis who is attracted to women, I would love to see more women embrace the bigger is better mantra. So there. Sue me.

But who the hell cares what I think? What do you think, female reader? Be a strong minded, independent woman and train to attack your own goals. I assume you are reading this because you are at least partially interested in this topic, so keep an open mind and be ready to drop your incorrect notions of strength training.

Being physically strong is a trait I would love to see more women become comfortable with, regardless of what it may or may not do to your appearance. Physical strength and lean muscle mass have very real physiological benefits that I will address, but the main agenda for today is breaking down your fear of “bulk”.

Strength training as an isolated enterprise will not be much of a factor in how your body is composed.


This is primarily based on four reasons. Genetics, hormones, the fact that strength training is low volume and diet.


Here’s the thing. For most of us who didn’t win the genetic lottery, our training has a very limited role in our body composition. It’s a catalyst, but not nearly as big as other factors like diet and genes from mom and dad.

That means that you can likely lift all the weight all the time and in reality, you could very likely see a marginal change in your composition.

Take this from Bret Contreras’ 2011 article on T-Nation.

A landmark study by Hubal used 585 male and female human subjects and showed that twelve weeks of progressive dynamic exercise resulted in a shockingly wide range of responses.

The worst responders lost 2% of their muscle cross-sectional area and didn’t gain any strength whatsoever. The best responders increased muscle cross-sectional area by 59% and increased their 1RM strength by 250%. Keep in mind these individuals were subjected to the exact same training protocol.(2)

(For a full read on genetic tendencies in muscle growth, I have linked Bret’s The Truth About Bodybuilding Genetics.)

While some women are definitely born with favorable predispositions to muscle composition, most women are not. Using empirical evidence from nearly five years of oversight of hundreds of people at Performance360, I’d venture an educated assumption that perhaps 5-10% of women fall into this category of Bret’s “best responders” to growing muscle. The kind of high performing athletes who don’t need a surplus diet in order to grow, who put on muscle if they look at a barbell.

These are the elite athletes, who are the fastest, strongest and whom lifts come very natural. They get to milestones faster than most an seemingly never plateau.

These are the women whose genetics cause them to drift towards high level competition and rise to the top, lending to the idea that all women who perform the sport or movements are physically representative of that look.


In all mathematical likelihood, that is not you.

Hormones and Muscle Fiber Type

Testosterone is a contributing factor to muscle growth and women do not produce enough of it to easily facilitate muscle growth like their male counterparts, up to 16 times less than men in fact (1).

In a 1993 study by Miller using needle biopsies, it was found that women had 45, 41, 30 and 25% smaller muscle cross sectional areas for the biceps brachii, total elbow flexors, vastus lateralis and total knee extensors respectively. (3)

It was also found that men have significantly larger percentage of Type-I muscle fibers in the arms than women, making it more challenging for women to put on size in their upper extremities.

Lastly, it was found that women have a lower proportion of their lean tissue distributed in the upper body.

Bulk fail, ladies.

Strength Training is Low Volume

This is a huge reason why strength training tends to not make athletes substantially bigger, regardless of gender. In a nutshell, muscle growth is stimulated by the tearing of type-I muscle fibers under 40 – 60% load in the repetition range of ten or more reps (oversimplification). The high reps cause the fibers to tear, fill with fluid (the “pump”) and grow larger.

Low-rep strength training using squats, deadlifts and presses in rep ranges of 1 – 5 under loads of 80% or more. This scheme targets more of our neural feed, our brain’s ability to communicate with our muscles and contract them faster.  We get stronger due to our central nervous system (CNS) becoming smarter and more efficient.

Strength training is of course going to target muscles but it’s the type-II fibers that are more geared towards athletic performance than they are for muscle growth. Type-II muscle fibers are go, not show. You’ll become stronger and faster, but often not bigger. The muscles don’t grow in the same manner as the Type-I fibers.

This low-rep, heavy strength training does not yield lactic acid, that “burn” or build up in our muscles from high reps cause muscular fatigue to set in. A study by Godfrey revealed that without lactic acid, we do not see the release of exercise induced growth hormone (EIGH) in high enough amounts to trigger benefit.(5)

Without EIGH to build muscle, we are trying to ice skate uphill.

Competitive power lifters depend on this low volume science as it’s imperative they maintain a their weight class while also increasing their strength. In fact, some even cut weight while simultaneously gaining strength.


The fourth and most important aspect of growing muscle, much more important than your actual training or genetics is your diet, specifically whether or not you’re eating fucking pizza all day.

For most of us, adding muscle requires a surplus like any economic principle. In order to grow muscle your caloric intake and protein consumption would need to be drastically higher than most women are used to.

I’ve coached a lot of women on diet. Looking back on it, maybe a small handful of them were naturally drawn to a bodybuilder type diet that would stimulate fast growth. Most eat like rabbits.

So, if muscle growth and “bulk” is dependent on diet, the only way a woman would get bulky via weight training would be to either strategically consume a prescribed surplus diet, or to achieve surplus accidentally by consuming a diet of junk food, high in fat and carbohydrates.

Most women who experience what they think is “bulk” upon a weight lifting program are really just carrying too much body fat. Body fat will take up substantially more space than compact muscle. One pound of fat bulges 18 percent more than a pound of muscle. Fat occupies 1.1 liters per pound while muscle requires just .9 liters per pound.(4)

So, that bulk you often see is often contributed by a terrible diet inflating the fat cells and taking up space rather than muscle growing out of control.

After all, that’s what bulk is. Space.

If you train heavy, ignore cardio and eat like shit. Yeah, you’ll get bulky. Just as a dude would.

If you follow a healthy diet, weights will achieve many favorable outcomes for you. Not among them is becoming bulky.

As you can see from the two filmstrips of strong women at our gym, heavy weight training effects all women differently. Each of them are in peak physical shape and are strong, independent women.

So, to summarize.

  1. Genetics – It’s largely up to mom and dad (and diet) whether or not you get big, not your training.
  2. Volume – muscle growth comes from high volume (10+ reps) at heavy weight at a slow and grow pace.  Strength training is typically performed at one to five reps with minimal lactate, thus minimal growth hormone.
  3. Testosterone – women have up to 16 times less than men. (Note: this was one fact I could not find a medical study for. I saw it referenced in over a dozen articles, but could not find the origin)
  4. Neural Feed – The majority of strength training work is on the nervous system and neural efficiency, not on muscles most susceptible to growing bigger.
  5. Calories – Bulking up typically requires a very specific hypercaloric diet that most women just aren’t on.

But what about the women I see who do get significantly bigger. When will weights add muscle?

Regardless of gender, weights will catalyze muscle growth in the following ways.

  • When you perform them in the appropriate rep range of ~10 or more multiple times per week, for months on end, in combination with the items below. 
  • When you completely avoid cardio.
  • When you are strategically on a caloric surplus diet.
  • When you eat like shit and don’t pay attention to what goes into your body.
  • When you have rare genetic tendencies and biochemistry to easily add muscle.
  • When you take performance enhancers as is not uncommon in professional competitive circles.

So unless you can check off the majority of those items, you won’t see a noticeable increase in muscle unless you want to.

The “Best Responders”

Earlier you may recall we mentioned that approximate 5-10% of women who are sensitive to easy growth. Do you feel like you may be in that category? If so, you’re not alone. A few of the ladies featured are, too.

So what. Own it. Embrace what science gave you and understand what a positive outlier and role model you can be for your friends and family. I challenge you to tell me any of those women appear disproportionate or “bulky”. If you do think that, then perhaps strength training is just not for you. I’m not here to sell judgmental, fear-based thinkers. I’m here to promote the accomplishments of those who embrace the possibility of getting stronger.

Building Muscle vs. Bulking

I see these two concepts as drastically different. To me, building muscle is about swapping a few pounds of fat in exchange for 5 – 10 pounds of muscle that often results in a neutral net shift on the scale. Bulking is the act of high-rep, heavy lifting with the sole goal to grow muscle. It is accompanied by a painstakingly high calorie diet that typically adds some body fat, and whom most don’t have the stomach for. Literally.

You are not, nor will you likely ever be bulking.

The truth is that any woman who possesses a lot of muscle has worked her ass off for it. It did not happen by accident and it did happen in a matter of a few sessions. You will never become bulky by accident. Ever.

Why You Should Drop This Train of Thought Entirely

Despite the fact I am a man writing a sales pitch to women, I like to think I have a fairly reasonable view on things as I am in charge for programming for a lot of people. That’s relevant because I am forced to understand common fears and common goals, and charged with the responsibility of blending the two.

Here’s a few reasons to lift heavy, ladies.

  • Fat Loss – Adding a few pounds of muscle will increase lean body mass and your metabolism to help you burn more fat.
  • Confidence – My favorite reason. Ditching fear-based thinking will make you a more confident, stronger woman. I see this transformation daily.
  • Bone Structure – It will improve your vitality and the structure of your bones as you age.
  • Superior to Cardio – If you think you’re going to get a more shapely ass doing cardio, you’re mistaken. Cardio strips, it doesn’t build.
  • Fun – It’s just bad ass to turn yourself into a woman who can lift with and often heavier than the boys. No two ways about it.
  • Opportunity to Inspire – Whether it be a body with a little bit of muscle on it or the feats you can perform physically, be an inspiration to other women to change their thinking.

Let’s now take an introductory look at Julianne and the role that power and Olympic lifting have played in her 30 pound fat loss transformation.

Julianne’s Story

Julianne Russell is a coach at Performance360, as well as ERY-T 200 yoga teacher and one of the most respected minds in San Diego when it comes to how the human body works. Julianne has dropped ~30 pounds since she began weight training and will tell you all of the ways she has been able to accomplish that.

Julianne has dropped 30 pounds in two years, and has recomposed her body through an intense focus on heavy power lifting and Olympic lifting. Specifically, the deadlift and the squat where she has lifetime PRs of 330# and 215#

What was included to achieve her figure on the right:

  • Lots of deadlifts, squats, cleans and presses. Julianne has a deadlift PR of 365# and back squat PR of 260#.
  • Lots of frequent heavy lifting.
  • A dramatic change in diet focused on her goals.
  • Did we say lots of heavy weight training?

What was not included to achieve her figure on the right:

  • A single jog
  • A single piece of cardio equipment
  • A single boot camp
  • A single FitBit
  • A single calorie log
  • A diet that contains lots of crap

So stay tuned.

We’ll be handing over the microphone to Julianne next time and invite her to share her story and interview in complete detail.

In Today’s Conclusion

The purpose of today was to inspire you to become strong. Your body will react how it reacts, and chances are overwhelming in your favor that you will not become bulky.

We’ve shared a bit about the biological factors at play that make becoming bulky very difficult for women. The vast majority of women who eat healthy and include heavy barbell strength training see their body’s accentuate in the manner they hope for. Larger, more defined glutes. Leaning of the midsection and strengthening of the upper body.

However, where writing this article saddens me is the fact that it’s needed at all. The great news is that with the popularity of weightlifting across the board, more and more women are embracing the physical and mental beauty of increasing their strength. And that’s a good thing.

Agree? Disagree? Let me know what you think, and if you liked it, please hit the SHARE button. 







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