Muscle ConfusionHere’s a strength training “principle” that gets prominent every few years. Right now there’s an infomercial touting the effectiveness of “confusing” your muscles in order to get better results, so I get a lot of questions about it.

The idea is you do different exercises for a given muscle and because of the variation your muscles get confused and are forced to adapt in some way that does not happen if you do the same exercise all the time. Uh-huh.

Let’s take a look at this. Every muscle in the body can do only two things; contract or relax. That’s what muscles do. When you bend your elbow it’s because your biceps contracts. To straighten your elbow your biceps relaxes and your triceps contracts to pull it in the opposite direction. Easy to understand.

If you bend your elbow with a twenty-pound dumbbell in your hand a few biceps muscle fibers contract. If you do it with fifty pounds, more biceps fibers contract. To get the absolute most biceps muscle fibers to contract you would have to lift the absolute most you could doing that movement. Also easy to understand.

Knowing that, does anybody really believe that somehow your biceps know that two weeks ago they were lifting a dumbbell, but last week they were lifting a barbell and this week they are lifting the handles of a biceps machine? And that knowledge inside the biceps causes them “confusion” and that confusion leads to bigger, stronger muscles than what the amount of weight itself would dictate? In other words, a 90-pound barbell curl would have an effect more than 90 pounds because of the confused condition of the muscle? Maybe it’s “like” 115 pounds just because of the added confusion. Does that sound plausible in this universe?

Moreover, your biceps is used to open doors, carry a laptop bag, lift groceries and hundreds of other things – and it’s expected to remember last week’s gym exercise but be confused that it’s not the same this week’s? Does that sound like how the rest of the human body works? Does your digestive system get confused because last Thursday’s dinner was spaghetti but this Thursday’s is sea bass?

This muscle confusion crap has a cousin. It’s the story about how you do a workout on Monday, Wednesday and Friday and then your body “expects” a workout on Sunday. But you don’t do a workout on Sunday and when you go back to the gym Monday your body is “shocked” by the surprise workout and therefore you get better muscle gains. Have you heard that one? The amazing thing about it is your body never figures out the pattern so every Monday is a total shock to the muscles. Please.

As I mentioned in the Welcome to My World audio recording, in fitness marketing lies sell better than truth. So infomercials are chocked full of lies that pander to people who trust blindly and don’t think things through. It’s a shame, but right this minute an infomercial and a certified personal trainer somewhere are both telling someone that muscle confusion will improve their results.

The truth is so much simpler. Lift the heaviest weight you possibly can for each muscle group, rest long enough to fully recover and build new muscle tissue, return to the gym and lift a slightly a heavier weight. Wash, rinse and repeat.



  • Carl

    Hey Pete: Love this article and just shared it with a friend of mine, who oddly enough talked to me about muscle confusion a few days ago. He supports that idea so I'm sure we'll have an interesting conversation when I see him again. 😉

  • Thanks, Carl. Let us know how you make out.

  • Yeah, that’s a good one. As if a muscle could really get confused!

    Take any sedentary individual and subject them to a confusing variety of harder-than-normal work for a few months and of course they should see improvements in muscle mass – not because of the confusion but due to the increased demands of their daily workload. I wonder what people do after those programs (which, I acknowledge, do seem effective at getting people through those first stages of fitness improvements) to continue seeing gains.

    As an example, I worked with a client yesterday who lost 4 pounds of muscle and 2 pounds of body fat during the past 50 days of doing the Insanity workout (P90X’s follow up program). I think it was from a combination of too little rest (6 days of 45-75 minute high intensity workouts each week), consuming less than a maintenance amount of calories (180 lb man doing ~60 minutes of intense plyometrics 6 days/week only consuming some 2400 kcal/day). His cardiovascular system is pretty fit from all of the volume he is doing, but clearly he has reached a level where the shotgun approach to scheduling workouts is doing him more harm than good.

  • Paul Robeller

    I'm having a tough time with this.

    I know a few people who I've watched them transform their bodies and overall fitness in a few months with P90x, specifically. And it seems by all the online testimonials, non solicited, that this 'muscle confusion' works incredibly! They've got the success stories all over the place.

    SCT makes 'sense', but is it truly getting fit? I think someone who is physical, using their bodies for their whole lives is going to be much better off when they reach their golden years.

    Rather than someone who focuses on 3 minutes of training 2 times a month.

    Show me a recent page of video and photo testimonials of SCT and then that would help. But, I don't see them. That would be undeniable proof of a life transformed. Of a body transformed.


  • StaticContrac

    I am not saying 60-90 minutes of exercise per day for 60 days will not make a person stronger or more fit. I am saying – as far as the strength training aspect goes – it is using a sledgehammer to kill an ant. Static Contraction training is about time-efficiency. Getting as much benefit as possible for as LITTLE time and effort as possible. If that matters to you – and I understand it does not matter to everyone – then you should look at SCT. Many people care about the wear and tear on their bodies created by saturation exercise routines.

    Before and after photos? This article might help you realize that they can rarely be trusted and, perhaps worse, they create very false expectations;

  • Aso

    I'm not surprised hearing this. Insanity workout program is crazy. I've tried it, my wife did also. Not enough rest between workouts. Within 2 weeks, you will be waking up with bones cracking everywhere. P90X on the other hand is a lot better, but I think working out 6 days a week is too much, especially when you work 40hrs a week. 4-5 days is plenty on that intensity while doing p90x. I've gained definition all over. My quads and calves grew as well.

  • Paul

    That’s a funny visual with the hammer/ant. 😉

    Yeah, regarding the photos … I actually see my friends face to face, so I’m pretty confident I’ve seen their transformations.

    Yes, that’s true there’s a lot of lies out there. But not all of them, for sure.

    Why not produce REAL photos / videos of SCT users? Where’s the accountability here? I don’t see or hear a round of current users singing the praises of SCT and supporting this with photos.

    Advertising and marketing is an extremely nonregulated medium and you are profiting by providing ‘facts’ and ‘scientific numbers’ — yet you don’t produce before and after photos. Just because some shysters lie about their photos, the fact that you don’t produce any speaks louder volumes than anything else.

    Believe me, I want the benefits of SCT, but I want the results more.

    It’s simple, produce the ‘Case Studies’ or ‘Testimonials’ with pictures of before and after and you’ll give credence to your ‘findings’.

    This is not an attack, don’t take it personal — just respond with what’s expected in your industry.


  • The problem for the honest guys with photos is people look at them and think, “That’s not so great. I’ve seen much more dramatic transformations.” So the liars have poisoned the well for the rest. In marketing, you are what is known as a “late adopter” in that you won’t experiment with a new idea until you see many other people do it first. That’s not a criticism. It’s just the way statistics operate. Some guys come in early, some much later. Some guys wait in line for the new iPhone, some get one 5 years down the road when they feel they’re sure it’s a good phone. Static Contraction training is unconventional so it gets adopted by people who like to try new things because they are naturally curious. After SCT is more popular I look forward to having you as a customer. But if you ever want to try SCT in the meantime, just pick up a really heavy weight inside a power rack adjusted to your strongest range of motion and try holding it 5 seconds. Make sure it’s so heavy you can’t hold it 6 or 7 seconds. And see how it feels. And then ask yourself, how could lifting the heaviest weight you’ve ever lifted in your life NOT build muscle?

  • Jack

    Hey Paul (and Pete),
    I actually did p90x a few years ago and I got ripped and stronger from it. However, programs like p90x are not sustainable- an hour of working out every day is extremely taxing on the body and I found myself tired and lacking energy after doing the program for a while. I guarantee the reason why p90x works for some people is because they burn a tremendous amount of calories every workout. The truth is that programs like p90x are near impossible to stick with because you will most likely give up or over train every workout and it just takes a lot out of you when you also have to worry about school or work.

    While I said I got stronger, I didn’t become massive from this program. Doing pushups and pullups will build some strength over time, but for the most part, doing a lot of pushups will only make you better at doing pushups. Progressive overload is very important when it comes to becoming bigger and stronger, and with pushups you use your body weight. Pushups and pullups just aren’t the best and most efficient way to take strength and size gains to the next level.

    As for the muscle confusion debate-
    The reason people believe in muscle confusion is that if someone completes the same exact workout several times in a row, the usefulness of that workout diminishes over time because there is no progressive overload. If I bench press weight “x” every week, it may become easier for me to lift that weight the next week. But if I never lift heavier than weight “x”, there is no stimulus for me to all of the sudden be able to lift weight “x+50lbs” which may be my goal. Because of this, people think that they need to change up their exercises and workouts to “confuse” their muscles and avoid hitting a plateau. But if you make sure you don’t over train and if you use the progressive overload principle, I guarantee you will see results every single workout (which should be everyone’s goal, right?).

    I now perform the SCT workouts once every eight days, and every day I am not lifting doing SCT, I am walking on the treadmill at a low intensity. Now I have a sustainable method to burn calories every day which keeps my bodyfat percentage in check, and I am lifting considerably heavier weights each and every SCT workout.

    Paul – from someone who has experienced both p90x and SCT, do yourself a favor and do the latter. You won’t have to worry about killing yourself with very demanding workouts every day and I can almost guarantee that you will see the best strength gains of your life for the short amount of time actually invested in lifting weights. It is everyone’s natural inclination to think “if I want to get really fit, I need to workout a lot every day” but this is not the case because your muscles grow when you rest and recover.

    Hope this helps. –Jack

  • Well said, Jack. Thanks.

  • Troy

    It`s not the muscle it`s the CNS that there manipulating. Look up Westside Barbell and the CONJUGATE method. The strongest people in the world use partials reps and use this method. They rotate exercises every week to keep there body adapting to different stress. Were talking 1200 pound squats and 800pounds bench presses.

  • Thanks, Troy. I like the WestsideBarbell site. They try to use good science. But they are writing for 0.01% of the population. These are guys that are prepared to lift 100 times more volume for 2% more muscle. They are competitive powerlifters who MUST use a full range of motion in order to compete in man-made events that stipulate certain artificial rules. Those rules don’t apply to building muscle and increasing strength in general. Most people can get at least 90% of the strength these guys have with 1% of the effort. That’s a bargain for most people who have no Olympic ambitions. So the guys at Westside have to use extreme techniques that the rest of us just don’t need. It’s just like the way 99.99% of us don’t need to drive as well as a Formula One driver, so why spend time practicing and learning to drive like a Formula One driver?

  • Troy

    Pete, I agree with you 100%. The injuries these people go through are also sometimes only fixed by surgery. Like full range bench press and pec tears. I was just trying to clear up some misunderstandings about so called muscle confusion and support what you say is valid by real world proof. I use PFT by the way and like what your doing.Thanks.

  • Hey Pete,

    This is an exciting potential for working out less.

    Couple things though:

    1. If we don’t have a gym membership or one of the SCT $2k plus machines, then how do was successfully use this system?

    2. I see P90x referred to here — there’s no doubt it works. Are you saying or proposing that it’s non-beneficial to workout this way?

    3. Does SCT tend to build larger muscles. Some guys are just big and bulky, but are not very functional or actually look that ‘in shape’. It seems, logically, that other types of ‘muscle confusion’ or ‘repetition’ type of workouts will aid in creating more definition to the muscles.

    Any help is appreciated,


  • Thanks, Mark. 1. You need access to heavy weights. There is no way to get around the physics of that. Because Static Contraction training is infrequent some people just pay the daily (visitor) rate at a local gym. This makes sense if you only visit 2 or 3 times a month. SCT uses common exercises that people can also do at home. But they need a power rack to limit range of motion and they need heavy weights.
    2. I’ve never said P90x and the other “insanity” (as they are advertised) workouts don’t work or don’t build muscle. What I say is they are grossly inefficient compared to SCT. Compare doing 3 SCT workouts lasing 25 seconds over a month to 25 ‘insane’ workouts of 60 minutes each in the same month; it’s 1,200 times more exertion. 1,200 times more! Plus you are far more likely to get injured with the ‘insane’ workouts than you are with SCT. And do you really believe push-ups will build more muscle on you than 600 lb partial bench presses will? I don’t.
    3. I can’t dissect here all the gym fallacies you allude to with question 3 but they involve the concept of guys with big muscles who aren’t actually strong. That never happens. Or that ‘bulky’ muscles are somehow not functional. They function properly. There is no logic to muscle confusion. Muscles don’t think. Yes, lower bodyfat helps muscle definition. So if you want better definition then you should lower your bodydfat. Whether doing 1,200 times more activity is necessary to do that is a debatable point.

  • Monico

    Paul, Keep in mind that SCT is a very efficient way to build muscle and increase strength. Not necessarily a way to drop fat fast. I’m sure P90X can take the fat off quickly, heck just go out and run for an hour a day 6 days a week and you will do the same thing. But I’m sure those people in the before and after photos can’t bench press more after 90 days then they could before they did P90X. I’m just saying don’t confuse building muscle with SCT, with getting fit which usually means losing fat.

    As for before and after photos, they are not that easy to get when you are trying to build muscle. I don’t know what your experience is with building muscle but I started lifting at the age of 39 because I was starting to feel weak. After 3 years of conventional weightlifting multiple times a week I had barely any increase in strength. I found SCT last January and I saw my strength increase rapidly. Just to give you an example I have one of those multiple stack weight machines that goes to 260 lbs. The most I could ever lift on it was 210 lbs for bench press and that was struggling for 2 reps. Two months into SCT I was able to lift 260 lbs for reps. I concentrate more on building muscle than losing fat so my before and after picture would surely not impress you. However, I run across friends that haven’t seen me in a while and they do notice I have been “working out”. Needless to say that building muscle is a very slow process. I’m sure the day I decide to go from 24% body fat to 10%, the transformation will be extraordinary.

    I now love going to the gym once a week and lifting more every time I go. SCT works! Plain and simple.

  • I did P90X religiously for several years and reduced my percent body fat from 26% to 10%. (See linked Web site for pictures.) I also met Tony Horton at a weekend Miami Beachbody retreat in April 2006. He is a really nice guy and sincerely wants to help people.

    As others have noted, P90X is not a sustainable program long term. I have other things I like to do in my spare time besides preparing for exercise, exercise, or recovering from exercise, even if the workouts are in my back porch. Moreover, much of the credit for the fat reduction goes to the rigorous P90X diet plan rather than the workouts.

    I basically abandoned P90X in late 2007 when I started graduate school while working full time. By the time I finished the degree in 2009, I was back to 21% body fat. I started the Body by Science (BBS) program of Doug McGuff and John Little in May 2010. This is similar but not identical to Static Contraction Training (SCT) though it follows the same idea of workouts that are brief, intense, and infrequent. I have been rather amazed at my muscle growth in only 12 minutes per week. My percent body fat is 18% and I hope to reduce it further with more strict adherence to a lower but sensible caloric intake. I will eventually post some “before and after” pictures to my Web site to contrast against those of P90X.

    The bottom line is that I think P90X does not allow enough time for muscle recovery to allow for the kinds of gains that programs like BBS and SCT allow. Obviously P90X does reduce body fat when followed strictly. While my cholesterol improved with P90X, I cannot comment yet on how these other programs affect it as I have not measured it lately.

  • rob matthews

    Hi Pete i get the comment about photos before and after,i couldnt get any up on the link you provided by the way, but there must be some guys out there who have been maybe bodybuilding the conventional way before trying sct, that have switched over to sct and managed to at least maintain their mass, or have increased size using sct. So would really love to see the size and quality in some photos of these people, there has to be some out there. I do rate the logic and sense of your routine , would just like to see some pics to spur me on , keep up the good work, thanks rob

  • Thanks, Rob. But don’t look for any before and after photos from my marketing. I won’t be playing that game. The well has been poisoned globally. The honest guys will never have the impressive photos you’ve seen thousands of times from the scumbags. I’m left to appeal to people’s reason instead of their emotion and I can tell you it’s way harder the way I’m doing it. Haha!

  • I am a trainer and helped a good friend win the “Maxmuscle” transformation contest several years back. They are a well known supplement company. She went from 220lbs at 5’9″ 40% bodyfat and competed at 130lbs at about 11% bodyfat. First, man I wish we had known about SCT then! The hours of training were ridiculous. Nevertheless, she did the transformation drug free (I’d swear on my mom/dad’s graves) but it took a whole year! Most of those amazing transformations you see on p90X are from folks who were not in that bad of shape to begin with. Or, perhaps some are pharmaceutically enhanced. Who knows. But I agree with Pete, for the most part these before and after pics are just not reilable.

  • Brian, I agree with you and Pete about the before and after pics. They are not reliable. My favorite pics are the ones that show the trainee in the exact same clothes in the before and after shot. I don’t know about you but when I lose even 5 pounds, my clothes get loose on me and these pictures claim the trainees lose 10 pounds or more and their clothes still fit them the same. Yeah right!

  • Pete, thanks for everything!!! I’ve studied your work for years now and have always respected every bit of it! Only thing is that I never really stayed consistent for long with the workouts for no good reasons. But… I did start in April 2010. I did no other methods of strength training but SCT and went from 160 lbs to 190 lbs at 5′ 11″ tall in 4 months. I am a martial arts instructor and have always had low body fat. The only thing I did besides SCT was went from approx 3000 calories a day to closer to 4000 to help with energy. I started dating a competitive bodybuilder (no drugs) and just for fun started ‘playing’ with more traditional routines even though I didn’t believe in them. I stayed consistent for 4 months and as I’m sure u know, I lost strength and size. I knew it would happen but I wanted to have the story of “see, SCT is the best!” Of course I’ve stopped playing and went back to the real deal. Last chest push was 765 for 14 seconds. Thanks so much!!!

  • John Varghese

    Hello Guys,
    I have been doing SCT for a few years and it has totally transformed my life. From fixing a medical condition to increased energy to a better overall quality of life. I purchased the Explosive Fitness equipment at full price and now need parts. As all of us know, getting support for these things is next to nothing. “Fixing” the machines bought us some more time, but its coming to a point where I need to get a new machine. I heard you guys are working on a new device. Please get it out soon. The method is addictive and some of my friends are not happy in working out the “reqular way”..
    Thanks again for all your research and common sense advise.


  • John, we hear you and we’re working on it!

  • Nick

    Hi Pete
    Love the new site
    I am 5,7 and now at 80kg (176lbs) and nearly fifty have been training with your systems for three and a half years now in the best shape of my life lost 10cms (4ins )off my waist and in avg gained 7,5cms(3ins) every where else arms ,legs and chest/back.
    Gone from 110kg(242lbs)bench press to 225kg(496lbs) legs press from 150kg(330lbs) to 400kg (881lbs) train once every ten days. Half body split.
    I agree that muscles do not know weather your lifting barbell , machine, rocks or a car! But your eyes and brain does. So I have been using power factor for six months and sct for six months
    The brain makes you stronger and your muscles grow and if you believe you can lift/grow you will so the switch keeps me fresh and improving
    It works for me may be it will work for others
    Thanks again

  • Leighan

    I have found a statement by Mike Mentzer that fits perfectly alongside the wise words of Pete for this article:

    “Aristotle (credited as the founder of logic) stated that the whole of logic is predicated on the Law of Non-Contradiction, that a thing is what it is and cannon be something else at the same time and in the same respect. In other words a muscle is a muscle-with its own distinct identity and qualities-it is not a mind, despite one popular bodybuilding “principle” of “muscle confusion.” Given that the principle of identity applied to human muscle tissue reveals that it cannot reason or properly use the principles of thought, one might wonder then how it might become confused.”

  • It ain’t the muscle that’s confused. Haha.

  • Leighan

    Exactly. When you consider a muscle is just that, a muscle, how could it possibly be confused, because a muscle doesn’t have a mind.

  • It’s just another dumb rationalization for never changing your workout frequency. “Stopped making progress? Switch to different exercises!” What is really required in 99% of cases is additional time off to fully recover and let new muscle grow.

  • Leighan

    And afterwards, progressively heavier weights, like you have stated many times. A lot of people train with the same amount of weights all the time, and still expect to grow. Of course they are not going to grow, the body has no reason to, as it has adjusted to that amount of stress; so why would it make more muscle than is necessary when it is already able to cope with what it has. Along with the fact it is constantly trying to preserve energy for life, it certainly isn’t, unless its stressed with even more weight.

  • Brian Schamber

    That is just one of the six-hundred and sixty-six Weider (Supplement Selling) Principles.

  • Muscle Confusion now there’s a piece of nonsense that been floating around the wonderful world of fitness hype and bro-science for as long as I care to remember.I think that it probably started like quite a lot of things in one or other of Joe Weiders publications.It sounds like something dreamed up by a journalist for a bit of headline catching.Well when you have a catchy phrase why waste it and indeed as the case seems to be, its been borrowed at the moment by one heavily marketed system to explain its supposed success.The thought of all those confused muscles just wants me want to go -Oh you poor things and comfort them ha ha.As you say Pete its not the muscles that are confused.

    A thought occurs to me-the owners of all those confused muscles- that just don’t know what to expect from one workout to the next could have some er interesting discussions with those that I occasionally meet who argue that-Their muscles don’t know how much they are lifting {literally true of course}so as long as they have pin point concentration their muscles will be just as stimulated as they would be if they lifted something heavier.Perhaps these muscles are confused too in a rather different way ha ha.

    My response to this sort of idea has usually to ask them to consider whether curling a very small coin with complete concentration{which of course they possess} would provide just as much stimulation to muscle growth and strength as a heavy dumb-bell.Some have got my point others have steadfastly maintained that they could.There is a word for this-delusional.

    One perfectly pleasant trainer with some twenty five years experience behind him even told me that his-ho hum mind muscle connection was in such a refined state of development that just shaving with a light weight wet razor gave him a terrific pump in his biceps.I promise that I am not making any of this up.Delusional-yes I think so.

  • Some trainers are literally in love with their muscles. And, of course, we know love is blind.

  • Brian T

    I think this concept is false when it comes to strength training because you are changing the intensity continually anyway and periodically the frequency as well.

    However, on exercises that are done regularly I think there is a lot of truth in giving the brain and nervous system a new challenge. I find this gives me better results with cardio, fat loss and agility workouts.

    In reference to fat loss, continually changing your bodyweight circuits appears to significantly increase the amount of calories burned with each session so you never stop getting the same results as you do at the start.

    Most people get great results initially and then it tapers off, and I believe it is due to neural adaptation.

    Going back to weight training, I’d say if you are using conventional workouts and are in the gym all the time then changing exercises a lot probably does help a bit because the workout is in such a plateau. But that’s only giving yourself a bit more neural training really and not solving the problem with lack of recovery and slow progress.