The p90x system has popularized the phrase “muscle confusion” with claims, within the infomercial, referring to the “training science of muscle confusion.” My question is this: Is “muscle confusion” based in “training science?” Oh, and, what the heck is “training science?”

Here is a portion of the p90x pitch:

Alright, muscle confusion… sounds good. Let’s see what a search of scientific research journals pulls up for me:

Only 10 results – hmmmm – that’s not usually a good sign…

Serotonin Syndrome – Muscle Rigidity and Confusion in the Older Adult.
Renal failure in a patient with…
Confusion between physicians & dentists about muscle-type pain…
Preventing falls and fall-related injuries in hospitals.

Nothing related so, I’ll stop there and spare you the rest of the list.

Sadly, “muscle confusion” doesn’t seem to be based anywhere in science.

Well, let’s go ahead and see what kind of research supports “training science:”

Basic science research and education: a priority for training…
Training and career development in clinical and translational science: an opportunity for rehabilitation scientists.
Science in Mental Health Training and Practice…
Eating for Performance: Bringing Science to the Training Table.

Not quite what I was looking for, but the list goes on and on.

Perhaps most perplexing is that a comprehensive research journal search with the phrases “muscle confusion” and “training science” yield absolutely no results! Tony Horton, have you lied to us all?!?

In fact, there are only two papers that come up relating to p90x – one is from Men’s Fitness (let’s throw that one out). And the other is from FireRescue Magazine, more detailed than Men’s Fitness, yes, but a far cry from the “training science” research I was hoping to find!

Okay, let’s give Tony Horton one more chance and find out what papers he has authored:

Another head-scratcher, neither “Tony Horton” nor “Anthony Horton” returned any results.

Oh well, I guess I’ll have to answer my own question from the top of this post.

So, what does “the training science of muscle confusion” mean?

My take is that it is essentially a nonsense term/phrase used for marketing to laypeople.

“Training science” can probably best be relabeled as exercise science (now this is a real phrase… in fact entire bachelor's degrees are labeled as such). Personally, I think exercise science is as easy to understand as “training science,” so I don’t know why they wouldn’t market it correctly in this way.

“Muscle confusion” seems to be very much a dummy term. From the marketing, it seems like the p90x folks are alluding to their programming and the manipulation of variables (sets, reps, mode, method, etc.). The actual term is “periodization” and this can take on a variety of shapes and sizes to elicit the result you’re looking for.

Perhaps the marketing magic-makers think the layperson is not capable of learning new words like “periodization?”

The bottom line?

I’ve watched the p90x DVDs and I think the creativity of exercises and simple exercise progressions are quite good.
Personally, I know at least 50 people (all happen to be current or former high-level athletes) who have tried p90x. None of them have completed the program.
I think it is shameful the way the fitness industry allows itself to market to people’s egos, fears, and insecurities. This product is no different.

If you want to try it, go for it! It’s way better than sitting on the couch and a gigantic step-up from Jane Fonda tapes or going to a commercial gym to mindlessly wander around. But, I must say it is an extremely aggressive way to start a training program and, much like CrossFit, you may be best served to begin a training program that is moderately paced and conservatively planned to get you prepared for the full regimen.

Remember, in the world of strength, conditioning, and fitness, it is NEVER an all or none proposition. Any system that makes you feel that way, guarantees results, or sets a time limit on your progress should likely be avoided.