‘Muscle Confusion’ Is Mostly a Myth

Photo: Herbert Gehr//Time Life Pictures/Getty Images

Recently, there’s been a surge in the popularity of workout programs like Bodypump, P90x, and ClassPass, all of which are based on “muscle confusion,” or the premise that constantly switching up your workout routine — i.e., “confusing” your muscles — is the pathway to fitness gains. It’s an enticing idea, as evidenced by the numbers: Since 2004, P90x has sold five million copies, and last year alone, ClassPass brought in over $60 million in revenue. Unfortunately, muscle confusion doesn’t work.

“All the crap you hear about your body needing a different stimulus each week or a new ‘workout of the day’ is garbage,” says Brett Bartholomew, CSCS*D, director of performance at Unbreakable, a Los Angeles gym that Yahoo called the most elite gym in America. “The number-one reason people don’t get results is that they don’t have the attention span to stick with something.” (At the Cut, Kathleen Hou once wrote that ClassPass is like “being in an open relationship with exercise.”)

Bartholomew, who coaches a stable of professional athletes, including last year’s Super Bowl MVP, Vonn Miller, told me that the key to getting fitter lies in adhering to something called “progressive overload.” And, years of exercise science support his assertion. Citing increases in strength and muscle size, the American College of Sports Medicine (ACSM) published an official-position paper in favor of progressive overload for resistance training in healthy adults, and a 2015 study published in the journal Frontiers in Physiology found that the best endurance athletes in the world follow progressive overload’s principles.

Unlike with muscle confusion, in which exercises constantly vary and no two days are alike, with progressive overload you work a specific muscle or function (e.g., your biceps or running) in a specific manner, progressively adding intensity and/or duration over time. Hard days are followed by easy days and prolonged periods of intensity are followed by prolonged periods of recovery. Repetition and consistency are key. Results don’t occur overnight but after months, and even years, of sticking to the same routine.

Vern Gambetta, a world-renowned athletic development coach and founder of the GAIN network, has trained hundreds of elite athletes including the New York Mets, Chicago Bulls, and Olympians. I recently asked him about muscle confusion. His reply: “It’s nonsense.”

Even though decades of exercise science and the most preeminent practitioners say it doesn’t work, programs based on muscle confusion remain popular because doing something new every day is far more exhilarating than the comparatively boring reality of progressive overload.

The psychological drive to seek what is new and exciting is an innate one; what’s new are the fitness programs designed to prey on that impulse. “Today, everyone desires novelty and endless stimulation,” explains Gambetta, “So running around and constantly switching what you are doing from one day to the next is in vogue.” And it’s true that, in some cases, the notion of muscle confusion may even spawn some quick results, especially for those going from doing nothing to doing something. But if what you’re after is long-term growth and development? “It just doesn’t work,”Gambetta says. “Physical adaptation requires specificity and patience.”

After my conversations with Bartholomew and Gambetta, I began to think: Might our waning patience and incessant desire for novelty in fitness be emblematic of a larger cultural phenomenon?

Earlier this year, the New York Times reported on research conducted by the firm Forrester showing that in 2006, online shoppers expected web pages to load in under four seconds. Three years later, that number was compressed to two seconds. By 2012, Google engineers learned that internet users expect search results to load within a mere two-fifths of a second, or about how long it takes to blink.

Author Nicholas Carr, whose latest book, The Shallows, explores the far-reaching effects of the internet, told the Times, “As our technologies increase the intensity of stimulation and the flow of new things, we adapt to that pace. We become less patient. When moments without stimulation arise, we start to feel panicked and don’t know what to do with them, because we’ve trained ourselves to expect this stimulation.”

A recent survey conducted by the Pew Research Center’s Internet and American Life Project found a likely side effect of our hyperconnected world is the “expectation for instant gratification.” I write “side effect” because it’s just that. There’s nothing inherently bad about expedient technology — I rely on it, and I’m just as guilty as the next person of becoming frustrated when the hourglass on whatever screen I happen to be looking at doesn’t empty fast enough. But when we expect this kind of constant stimulation and instant gratification in other areas of our lives, it can become problematic.

The important stuff in life demands patience. Relationships. Scientific discovery. Learning. Reading a book. These things take time, repetition, and, occasionally, can be wildly boring. Many people fail at these endeavors for the same reason they fail at fitness: an inability to resist what is new, exciting, and different. Although he was referring to fitness, when Bartholomew said “[t]he number-one reason people don’t get results is that they don’t have the attention span to stick with something,” he could have been speaking about anything in life.

Understand: Stick-to-itiveness is not easy, especially in our one-click culture. But what if the same strategies Bartholomew uses with the best athletes in the world could help keep us on course — and not just in our fitness pursuits, but in other areas of our lives?

“I preach purpose and process,” Bartholomew says. “Purpose means before making a decision asking yourself, ‘What utility is this going to provide; why am I going to do this?’ And process is about a mind-set. Knowing that following a certain set of steps, even if they aren’t immediately gratifying, will lead to enduring satisfaction and fulfillment.”

Purpose and process. It’s not only elegant, but its efficacy is supported by science. Researchers have found that reflecting on your purpose increases what social scientists call “goal-directedness,” or your ability to stick with distant goals. A 2015 study published in the Proceedings of the National Academy of Sciences found that people who reflect on their purpose and core values are more likely to stick with hard health-behavior changes, like exercising more for sedentary people. And, as Science of Us has previously covered in great detail, focusing on the process is linked to long-lasting performance, well-being, and fulfillment.

In the gym, and in life, long-term growth demands patience, consistency, and most of all, hard work. If you ever find yourself tempted to deviate from what in the moment may seem like a boring workout program —or, worse yet, romantic partner or vocational challenge — pause and reflect on your purpose and process. Because rare is it may be, patience is still a virtue.

Brad Stulberg is a columnist for Outside Magazine, where he writes about health and the science of human performance. Follow him on Twitter @Bstulberg.

‘Muscle Confusion’ Is Mostly a Myth