The Truth About Muscle Confusion: Is Your Workout Routine Varied Enough?

Strength and conditioning experts Tony Bonvechio and Mike Mejia address the concept of "muscle confusion."

The basic idea of a good strength program is to challenge your muscles. Instead of sitting on the couch, you're squatting, lifting, pressing, pulling and twisting. This strengthens your muscles and generally makes you a bigger, stronger and faster athlete. With that in mind, here's a terrifying concept: bored muscles—i.e., muscles that have become lazy, disinterested and lethargic due to a repetitive routine that no longer challenges them.

Essentially, bored muscles have adapted to your workout and will not become bigger or stronger if you continue it. To combat bored muscles and plateauing, you must change your workout routine on a regular basis. This theory, known as "muscle confusion," has gained acceptance in recent years. Programs such as P90X use muscle confusion as their mantra, swearing that constant variety prevents plateauing and is vastly superior to traditional 10- or 12-week strength programs.

Can muscles really get bored? For that matter, can they really get confused? How much variety do you need in your strength program? STACK talked to Tony Bonvechio, strength coach at Cressey Performance, and Mike Mejia, CSCS and founder of BASE Sports Conditioning Inc., to find out just how varied your strength program needs to be.

The S.A.I.D. Principle

Many of the workout programs that emphasize muscle confusion contain a dizzying number of exercises. If you follow them to a T, you'll be doing hundreds of exercises each week. Is that much variety really necessary? Not exactly.

"Muscles need to be exposed to similar exercises over and over so they can adapt by getting bigger and stronger," Bonvechio says. He specifically points to the S.A.I.D. principle, an acronym for Specific Adaptation to Imposed Demands, as an argument against using so many different exercises.

(Learn more exercise principles that determine your success.)

The S.A.I.D. principle states that the body changes based on what it does over and over. When faced with the same movement on a consistent basis, it makes certain adaptations—such as stronger muscles, increased joint flexibility, and thicker tendons and ligaments—to adjust to that movement. It's not unlike developing a callous. If your toe continually rubs against the side of your shoe for days on end, your body will adapt by creating a patch of rough skin there.

"The whole point of exercising is to make an adaption. If you're constantly doing new exercises, you're not giving your body much of a reason to become bigger and stronger. You're not letting your body adapt in anticipation of performing certain movements," Bonvechio says.

But Don't Muscle Confusion Programs Work for Some?

Of course. Many workout programs based on muscle confusion require a big time commitment—up to six days a week for an extended period of time. (Most of the original P90X workouts lasted an hour or more.) Obviously, that beats the heck out of sitting on the couch, and it can help people lose weight and increase muscle tone. But the reason some find it helpful has little to do with "muscle confusion" and more to do with a commitment to working out nearly every day.

Muscle confusion is simply a buzzword that plays on athletes' fear of wasting their workouts. "Muscles don't get confused," Bonvechio says. "Your brain may take a while to learn new exercises, but muscles don't get confused."

So although certain muscle confusion workouts burn calories, increase muscle tone and leave you plenty sore, they aren't the best workouts to do if you're looking to become a bigger, stronger and faster athlete.

How Much Variety Do I Need?

Although your workout program doesn't necessarily need to constantly cycle in different exercises (like a muscle confusion program), a degree of exercise variety is beneficial.

"At least some exercise variety is important to keep athletes interested and motivated, as well as to help ensure more balanced development," Mejia says. "Areas like the scapular stabilizers, the posterior chain and the core all need to be targeted."

Mejia believes some variety helps avoid imbalances and keeps things fun for athletes. H e works in movement variety with accessory exercises. He says, "If I want to include some anti-extension core work two times a week, one day I might go with a TRX Fallout and the next a Slide Board Body Saw."

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However, there's nothing wrong with repeating the same major lifts (or slight variations of them)—such as Squats, Deadlifts, Cleans and Bench Presses—on a regular basis, as long as you're using what is known as progressive overload.

Progressive overload refers to changing the sets, reps, load, rest periods, range of motion and other factors that make an exercise progressively more challenging over time. Slowly increasing the amount of weight you lift is one of the best ways to use progressive overload in your training. If you Squat regularly but do the same number of reps with the same weight every time, your gains will diminish, and eventually you'll plateau. But if you regularly increase the weight, your gains will continue unimpeded.

If you do the exact same routine using the exact same variables—weight, sets, reps, rest, range of motion—you will plateau and your gains will stop. If you see a program that never asks you to change those variables in a way that increases difficulty, it's junk. Any program worth its salt has progressive overload built in to help you avoid plateauing.

Both Mejia and Bonvechio know the importance of progressive overload. "Variety doesn't just come in the way of movement patterning," Mejia says. "One week, I might switch an athlete from a 5x5 protocol on their core lifts to a 3x3 and 2x8. This is a nice way to avoid training plateaus and force the body to adapt without having to simply change exercises every workout."

"Stick with the same exercises for awhile, and progressive overload by constantly increasing weight or reps," Bonvechio says.

Strike a Balance

No need to lose any sleep about "muscle confusion." A good strength program for young athletes will include a set of core lifts repeated on a weekly basis, although with different sets, reps, weight, etc., while also swapping in certain accessory exercises to address muscle imbalances and keep things fresh.

It will also include plenty of progressive overload, changing the variables to make the exercises more difficult over time and consistently forcing your body to adapt.

"I think the answer lies somewhere in the middle," says Mejia. "The key is striking the right balance between the two so that your athletes are progressing without feeding into existing muscle imbalances and movement deficiencies by simply doing the same exercises all the time."

This 12-week plan is a great example of a routine that has enough variety to keep you on your toes and address any muscle imbalances but also builds strength and muscle.

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