The problem, according to some experts, is that it makes no sense from a fitness standpoint because there’s actually no such thing as “toning.” Say what? That’s right: It’s a myth workout pros are increasingly speaking out against.
So, if toning isn’t real, what are women actually doing in their sculpting classes?
The myth about muscle growth and “bulking up”
First of all, the term toning doesn’t exist in exercise science, says Polly DeMille, RN, MA, an exercise physiologist at the Hospital for Special Surgery. It’s a term used as shorthand for the way bodies often appear when they’re in shape. “If you lose some body fat and you build a little muscle, everything will look and feel firmer,” she explains. And since many women express fear of putting on “bulk,” trainers promise “tone” instead, despite the fact that it all comes down to muscle hypertrophy. (That’s science speak for growth.)
“Muscles are only able to grow, shrink, or stay the same,” explains Brynn Putnam, a Harvard-educated former pro ballerina who studied with top athletic coaches before creating Refine Method. So, no matter what kind of workout you do—heavy or light weights, fast or slow, high rep or low rep—the process of building muscle is the same.
It’s a point The Fort NYC founder Dan Trink recently laid out in a blog post on strength training. “As far as muscle growth, there are different kinds: cellular increase in size or an increase in cross-sectional area,” he says, but the differences those make when it comes to training are “splitting hairs. Any time you train a muscle, it’s going to grow.”
If this is true, why do different kinds of resistance training lead to one person ending up with long, firm, slim limbs, while another ends up with huge bicep bumps popping out?
You cannot lengthen muscles no matter how much you exercise
The shape of your muscular structure is all about your unique body.
First of all, many different factors—like body size, body composition, hormones, and age—affect how quickly and efficiently you build muscle. Your genetics even influence the kinds of specific muscle fibers you inherit. Then, there’s body fat: The less you have, the more visible your muscles will be underneath. Finally, how long your skeletal muscles are is determined by the length of your bones.
There’s one aspect to training that may cause you to appear “longer,” but it shouldn’t be confused with actually changing the length of the muscles. “With things like yoga and Pilates, you can gain flexibility in the chest muscles and hip flexors, so you stand up straighter, and it’s going to look like everything’s a little longer,” DeMille says.
Barre3 Director of Training Lisa Schale-Drake says that’s a phenomenon they definitely see with their method, which draws from some principles of Pilates. “Because our workout helps build strength and balance, many people do find that they stand taller. The lift is through our focus on core strength, posture, and energy,” she explains.
Toning is just a synonym for strength training
Look, of course appearing toned is possible, if what you’re looking for is to have slightly defined muscle that makes your limbs appear firm. But the nitty gritty of the term “tone” matters, as fitness options become more ubiquitous and some workouts inevitably make promises—of having a magic formula to turn any body, regardless of genetics, into a long, lean physique, for instance—science says they can’t keep.
The bottom line is this: Fitness experts have varying ideas on the most effective ways to build muscle. (That’s another story…or maybe another five stories.) But you should know that it’s all coming from the same place. You’re just lifting heavier, or more often, or with more reps, adding some combination of time and tension that leads to either a little, or a lot, of growth.
“Women should be doing strength training regardless. So if thinking of it as toning gets them to do it, that’s a good thing,” DeMille says. (Why women are constantly being sold certain kinds of body-shaping workouts is, again, a whole other important story.) “But it’s the same thing: Your muscle is just getting stronger.”
Doesn’t stronger sound way better than toned, anyway?
This story was originally published on April 27, 2017; it was updated on July 5, 2018.