'You can't tone muscle you haven't built' — I'm a personal trainer, and here's why I choose weightlifting before Pilates

Tom's Guide

06-07-2025

Before I receive a barrage of abuse, can I just say, I don't hate on Reformer Pilates. In fact, I'm about to embark on a 30-day fitness challenge, swapping CrossFit for Reformer to see what will happen — physically and mentally — to my body.
Which brings me straight to the point — you can't tone muscle you haven't built.
Firstly, I'd like to caveat by saying I can't stand the term 'toning muscle.' Essentially, though, it just means creating leanness, muscle definition, firmness, or shape, rather than significant muscular size.
But you can't do that to muscles that don't exist, and building muscle isn't easy to do.
Before the Pilates purists come for me, at the end of the day, exercise in a way that makes you happy and fulfilled. But if you're interested, read on to find out why I prioritize weightlifting over Pilates for building muscle, and the benefits of both for your training routine.
There are many reasons you should consider taking up Pilates. Firstly, an hour of Pilates can do for your body what many other training methods can't and won't: build mobility, flexibility, pliability, muscular control and endurance, strengthen your joints, muscles and bones against injury, develop core muscles of steel and create posture even ballet dancers would envy.
I'm not exaggerating, either. The Pilates lovers I know swear by it, particularly the Reformer, for changing their bodies for the better.
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But that lean and sculpted physique you're eyeing up? You need to build that muscle using muscle-growing principles, and Pilates, though brilliant at strengthening and "toning" using high reps, light weights and bodyweight resistance, isn't the gold standard of building that muscle.
In short, they're not interchangeable methods of exercise. Hence, different training principles yield different results (with some crossover, obviously).
If you really want to grow noticeable muscle size, it comes down to a combination of resistance training, recovery, protein intake and progressive overload principles.
So let's talk about that very process — hypertrophy. In the hypertrophy vs strength training debate, it's crucial to understand that these training methods aren't the same thing, and you won't train the same way for both.
Strength training builds strength, and hypertrophy training builds lean muscle mass.
Building strength doesn't mean your muscles automatically grow in size; strength training alters the muscular power output, whereas hypertrophy increases the size of muscle fibers.
So, the best way to build muscle is to resistance train with progressively heavier weights, adapting load, reps and sets over time to adequately challenge muscles and stimulate growth.
Oh, and we love using compound exercises (moves that hit multiple muscles, like squats) for best results.
Once you've grown the muscle, muscle definition comes down to body fat percentage. Losing fat and gaining muscle creates the overall appearance of a lean and sculpted physique — a process called body recomposition.
If the muscle isn't grown, there's nothing to tone, so while Pilates instructors will tell you the method creates a sculpted, lean physique, muscle-building should be the priority.
It's also important to look at the muscle fiber types when considering exercise. Slow-twitch muscle fibers are recruited during sustained efforts of exercise at a lower intensity, like Pilates or jogging, when you'll use your aerobic energy system and your muscles require oxygen.
On the flipside, lifting heavy weights and adopting sports like powerlifting trains your fast-twitch muscle fibers and supports short, sharp efforts using your anaerobic system. In this case, muscles don't require oxygen, but efforts are shorter and faster.
Pilates won't train the same muscle fiber types as strength training, and you'll find that Pilates adopters and long-distance runners will have a different muscle make-up than your weightlifters and sprinters.
The same goes for light lifting and higher reps — this taps into muscular endurance and is typically found more within a Pilates setting than with 'true' weightlifting.
We know that studies show lifting for fewer sets and reps at a heavier load and higher intensity is more effective and efficient (read: Work out less and get better results — a new study says this is exactly how) for gains than the former.
It's not to say that training principles like Pilates, calisthenics, gymnastics and other forms of bodyweight training aren't incredibly beneficial for your muscles.
But if your ultimate goal is to grow muscle, this isn't Pilates' arena — weightlifting and strength training are where you want to be.
So, when a Pilates instructor says he or she will sculpt and tone your muscles, you better make sure you're building them first.