Personal Trainer Course Series: Women Can Lift Without Bulking

One of the most common concerns I hear from women when they first start training is, “I want to get stronger, but I really don’t want to get bulky.”

It’s an understandable worry. For years, the idea that lifting weights would automatically lead to big, bulky muscles has shaped the way women approach fitness. And even though attitudes are slowly shifting, that fear still comes up regularly, even from women who are excited about resistance training but unsure what to expect from it.

As a trainer who works with women every day and someone who teaches others through personal trainer courses, I want to help clear things up. And now, thanks to a large new study published in 2025, we’ve got strong evidence that can finally put some of these worries to rest.
So let’s look at what the research says and how we can use it to build confidence around lifting weights.

What Did the Study Actually Find?

This 2025 study by Refalo and colleagues was a systematic review and meta-analysis, which basically means it pulled together results from a large number of smaller studies to look at overall trends. In total, it analysed the results of 29 studies involving over 2,800 healthy men and women aged 18 to 45, all completing the same resistance training programmes.

The researchers compared muscle growth between men and women in two ways:

1. Absolute muscle growth – the actual amount of muscle added, for example, centimetres of muscle thickness or grams of lean mass
2. – the percentage increase in muscle size from where each person started

And here’s what they found:

• Men experienced slightly more absolute muscle growththan women, especially in upper-body areas like the chest, arms, and shoulders.
• But when muscle growth was looked at as a percentage change from baseline, the results were nearly identical for men and women.

In other words, women gained muscle at the same rate as men. Because they usually start with a smaller amount of muscle, the total increase was less but the response to training was remarkably similar.

Why This Matters for Women Who Don’t Want to “Get Big”

If your concern is about “bulking up”, this study provides helpful reassurance.

To gain a visibly muscular physique, the kind that looks noticeably bigger, you need to combine specific training such as moderate-to-high volume, heavier loads and close-to-failure effort, with other factors like high-calorie intake, sufficient protein and long-term consistency. It’s a slow process that requires deliberate intention.

If your goal is to feel stronger, improve tone and posture and support overall health, that’s absolutely achievable without a large increase in muscle size.

In fact, most women who train two to four times per week and eat a balanced diet will improve strength and body composition without developing significant muscle mass. What they will notice is better muscle definition, increased energy, and better movement in daily life.

And crucially, this study shows that muscle development isn’t something women need to fear. It’s a natural and positive adaptation, one that responds in a predictable, proportional way.

Do Women Need Different Exercises Than Men?

One of the most valuable parts of this study is that the men and women all performed the same exercises, same programme structure, same intensity, same movements.

That means squats, deadlifts, bench presses, rows, lunges and other foundational lifts worked well for both sexes. There was no need for gender-specific exercise routines.

This is something I often explain to clients: the exercises themselves don’t need to change just because you’re a woman. The body responds to resistance in the same way, by adapting and getting stronger. The difference lies in how we use those exercises to reach different goals.

If your goal is lean strength or improved posture, we might use lower to moderate loads, fewer sets or more variety in movement. If your goal is hypertrophy, we’d adjust volume, intensity and recovery accordingly. But the actual movements? Those stay the same.

Strength Doesn’t Mean Size

One of the most encouraging things about resistance training is how quickly you can start feeling stronger, which is often long before there’s any visible change in muscle size.

In the early stages of training, most of the improvements come from neuromuscular adaptations: your brain gets better at recruiting your muscles efficiently. You learn to move with more control, stability and power.

And this strength benefit matters. It helps with everything from carrying shopping bags to reducing injury risk, from improving athletic performance to simply moving better day to day.

Importantly, these gains don’t require a large increase in muscle size. You can get stronger, more mobile and more capable without ever looking bulky.

How to Train for Strength Without Size

If your goal is to get stronger, move better and feel more confident without significantly increasing muscle size, here are a few simple principles to guide training:

• Train 2–4 Times Per Week: You don’t need to be in the gym every day to see results. Two to four well-structured resistance sessions each week is ideal for most women. It’s the kind of balanced approach we promote in our personal trainer courses. It’s effective, realistic and sustainable.
• Use Moderate Weights & Controlled Reps: Choose a weight that challenges you but still allows good form. Aim for 8–12 reps with control, focusing on technique rather than lifting as heavy as possible.
• Focus on Full-Body Movements: Compound exercises like squats, lunges, deadlifts, rows and presses work multiple muscle groups at once, improve overall function and provide the best return for your time.
• Prioritise Recovery: Rest days aren’t optional, they’re essential. Allowing time for recovery helps your body adapt to training without adding unnecessary stress that could drive excess fatigue or muscle soreness.
• Eat to Support Your Goals: You don’t need a calorie surplus, that is, extra food, unless you’re actively trying to gain size. A balanced, nutrient-rich diet that supports your training and lifestyle is more than enough.
• Listen to Your Body: Feeling energised, moving better, and progressing steadily are the real signs of a successful programme, not how much muscle you can see in the mirror.

Why Resistance Training Matters

Beyond strength or appearance, resistance training has other important benefits, especially for women.

• It supports bone density, which is key for reducing osteoporosis risk later in life.
• It improves metabolic health, helping with blood sugar control and fat distribution.
• It enhances posture, balance, and coordination, which matter for everything from running to standing comfortably at work.
• It can even support mental wellbeing, with growing evidence linking strength training to improved mood and reduced symptoms of anxiety and depression.

Whether your goal is to feel more confident, move better, protect long-term health, or just enjoy the process, resistance training has a role to play.

Final Thoughts

If you’re worried that lifting weights might make you bulky, I hope this has helped offer some clarity and maybe even shift your mindset.

The truth is, muscle doesn’t appear overnight. Resistance training won’t suddenly transform your body into something you didn’t ask for. But what it will do is improve your strength, confidence and quality of life in ways that go far beyond aesthetics.

As a coach, I want you to feel in control of your training. That means understanding how your body responds, knowing the science, and choosing the approach that aligns with your goals, whether that’s strength, tone, endurance or simply feeling better.

You don’t need to train differently just because you’re a woman. You just need to train in a way that feels right for you.

References

Refalo, M.C., Nuckols, G., Galpin, A.J., Gallagher, I.J., Hamilton, D.L., & Fyfe, J.J. (2025).
Sex differences in absolute and relative changes in muscle size following resistance training in healthy adults: a systematic review with Bayesian meta-analysis. PeerJ, 13, e19042. Click here to review the full research article/a>.

Build a Career Supporting Women’s Health Through Fitness

If you’re passionate about women’s health and want to build a career helping women feel stronger, healthier, and more confident, our Women’s Health & Exercise Specialist & Master Diplomas™ are the ideal place to start. These courses are perfect for those looking to become a personal trainer with a special focus on female clients. You’ll gain a deep understanding of the physiological and psychological factors that affect women at different life stages, from pregnancy to menopause and beyond. And the science backs it up: a 2025 meta-analysis of 29 studies found that while men experienced slightly greater absolute muscle growth, women built muscle at the same rate relative to their starting point, showing that women respond just as well to resistance training as men. With expert-led modules and real-world applications, this course will give you the knowledge and skills to support female clients with evidence-based training that truly makes a difference.

Women’s Health & Exercise Specialist/Master™ – Distance Study, In-Person & Live-Virtual

Course Info

Get Started

View Dates