Does Pilates Build Muscle?

Does Pilates build muscle? Somewhat, and very unevenly. The best controlled study on the topic found real hypertrophy in the abdominal muscles after 9 months of training, but a follow-up study by the same researchers found almost no growth in the deeper hip and lower back muscles over the same timeframe.

That split result is the honest answer, not a marketing line in either direction. Here's what the actual MRI data shows and why Pilates seems to build some muscle and not much of the rest.

What does the research actually show?

Two studies, same research group, same 36-week Modern Pilates protocol, same twice-weekly frequency, different muscles, different results.

A 2012 study in Medicine & Science in Sports & Exercise used MRI to measure abdominal muscle volume in 9 inactive women before and after 9 months of Pilates. The rectus abdominis grew by 21% on both sides, a statistically significant change, and the obliques and transversus abdominis on the dominant side grew by 8%. The researchers also found Pilates eliminated a pre-existing side-to-side asymmetry in those muscles.

A 2020 follow-up in Sports Health, using the same training protocol on 12 different inactive women, measured the quadratus lumborum, iliopsoas, piriformis, and gluteal muscles instead. This time, the pre-to-post changes in muscle volume were small and not statistically significant. The authors concluded the benefits of Pilates for those muscles likely come from neuromuscular adaptations, meaning better coordination and control, rather than the muscles actually getting bigger.

Both studies are small (9 and 12 participants) and had no control group, so treat the exact percentages as suggestive rather than definitive. But the pattern, strong abdominal growth alongside flat results in the hips and lower back, lines up with how Pilates actually trains the body.

Why does Pilates build some muscles but not others?

Pilates asks your core to brace and stabilize through nearly every exercise, for a very high number of repetitions, at relatively light intensity. That combination, frequent sustained tension on the abdominals specifically, appears to be enough of a stimulus to grow that muscle group over many months.

Your glutes, quads, back, and shoulders don't get the same treatment. Progressive overload, gradually increasing the demand placed on a muscle over time, is the clearest known driver of hypertrophy in those larger muscle groups, and that usually means adding external load. Standard Pilates relies mainly on bodyweight and lighter resistance bands at a fairly fixed intensity, so there's less of a lever to pull as you adapt.

Is Pilates the same thing as strength training?

No, and it isn't trying to be. Pilates is built around control, core stability, breathing, and flexibility, with muscle activation as a byproduct of holding and moving your body precisely. Strength training is built around progressively loading a muscle until it has to adapt by getting bigger or stronger. They overlap, but they're optimizing for different things.

If you've ever wondered whether resistance bands are a legitimate substitute for free weights, the comparison is useful here too: bands can apply real, increasing tension if you progress them deliberately. Standard Pilates generally doesn't push that progression the same way, which is a big part of why its muscle-building effect looks so concentrated in the core.

Can you build muscle with Pilates alone?

Probably some, mostly in your core, and especially if you're new to structured exercise and get novice-level gains from almost anything. What the evidence doesn't support is expecting Pilates alone to meaningfully grow your glutes, legs, or upper body. If visible, broad muscle growth is actually the goal, the fundamentals matter more: enough sets, enough mechanical tension, and progressive overload over time, the same levers any resistance training depends on.

Should you do Pilates if you're trying to build muscle?

Yes, just not instead of resistance training. Pilates is a reasonable low-impact addition on recovery days, and the core control and hip stability it builds tend to carry over into better technique on your main lifts. Treat it as a complement to a training plan built around progressive overload, not a stand-in for one.

This is where Ori, OneFit's AI coach, is actually useful beyond just picking exercises. Tell it what you have access to and what your week looks like, and it can slot Pilates or mobility work in alongside your strength days instead of treating every session like it needs to be maximal effort.

Let OneFit AI build the plan for you

OneFit AI generates a personalized plan from your goals, picks the exercises, and adjusts as you get stronger. Free to download.

FAQ

Does Pilates build muscle? Somewhat, and unevenly. A controlled MRI study found the rectus abdominis grew by 21% after 9 months of twice-weekly Pilates, but a follow-up study by the same research group found no significant growth in the quadratus lumborum, iliopsoas, piriformis, or glutes over the same timeframe. Pilates builds some muscles more than others.

Is Pilates as effective as weight training for building muscle? Not for most muscle groups. Weight training applies progressively heavier external load, which is the clearest known driver of hypertrophy. Pilates relies mostly on bodyweight and resistance bands at a fairly fixed intensity, so it doesn't apply the same progressive overload to large muscle groups like the legs, back, or chest.

Can you build muscle with Pilates alone? You can likely build some muscle in your core and improve muscular endurance and control almost anywhere, especially if you're new to structured exercise. But evidence for meaningful size gains in your glutes, legs, or upper body from Pilates alone is weak. If broad muscle growth is the goal, pair it with resistance training.

Why does Pilates tone some muscles but not build others? Pilates emphasizes core bracing and control through a huge volume of light-load repetitions, which seems to be enough stimulus for the abdominals specifically. Bigger muscle groups appear to need heavier, progressively increasing external load to grow substantially, which standard Pilates doesn't provide.

Should you do Pilates if your goal is building muscle? It's not wasted time. Pilates builds core control, hip stability, and flexibility that make your lifting technique better, and it's a low-impact option on recovery days. Just don't expect it to replace progressive resistance training if visible muscle growth across your whole body is the goal.