By Nick Tumminello

I prefer to talk about the art aspect of training (and nutrition) rather than reviewing the scientific literature. That said, I champion taking a more science-based approach to training – because I think training is the art of applying the science.

When you promote taking a more science-based approach to training (and nutrition), you’re sure to meet a host of common arguments against science. In this article, I’m providing my direct responses to the ten most common arguments against science I see used by personal trainers, strength coaches, rehabilitation specialists, and nutrition professionals alike.

Although it seems like there are endless types of arguments promoters of pseudoscience and nonsense use, there are really only three. Before I address and respond the 10 specific arguments against science this article focuses on, I want to first cover each of these three categories and discuss a few key points on each.

 

The 3-Types of Arguments Used by Promoters of Pseudoscientific Claims and Highly-Questionable Practices

As a fitness educator who champions skepticism, taking a more science-based approach to training (and nutrition), and who challenges pseudoscientific and non-scientifically founded practices in the fitness, nutrition and health field; I’ve become familiar with how people rise to the defensive of the claims they make that are based on insufficient evidence.

The first thing people usually do who make unjustified or unjustifiable claims is argue that what they’re claiming is objectively real. They’ll often do this by appealing to logical fallacy such as the appeal to popularity fallacy or the appeal to history or tradition fallacy, to name two of the more common ones. When asked to provide objective (scientific) evidence to back up their objective claims that warrant it, which they’re unable to provide, they then transition from arguing that what they’re claiming is objectively real to arguing that what they’re claiming is (subjectively) helpful. This second type of argument is demonstrated by common statements like, “If it makes my clients, athletes or patients feel better (i.e., they get something out of it), I use it.”

Well, if it’s all about using whatever makes people “feel better” – if that’s the standard – than anything that makes people feel better is justified, from drugs to hugs. I have to use extreme examples like that to highlight the fact that clearly these well-intentioned practitioners don’t truly believe that “everything has its place”, because none of them are using progressive hugging programs or telling their clients, athletes or patients to get their medicinal marijuana card.

For every trainer or coach who claims they use something because “it works in practice,” there is a long list of other trainers and coaches who make mutually contradictory claims, that are saying the exact same thing about the practices they use. This demonstrates that simply having trained high-level athletes or having had any level of training success in no way means that everything you claim to be legitimate is such. Heck, the practitioners who make these types of statements, as though it provides sufficient “proof” of the validity of everything their claiming, are the very same people who reject these types of statements when they’re coming from other trainers and coaches who use a conflicting school of thought. We’re all well aware that if you want to know what’s wrong with a particular training school of thought, just ask a practitioner who follows a different, conflicting school of thought.

As I’ve just identified, this blatant inconsistency in thinking is really just a lazy attempt at avoiding the intellectual work required to critically examine one’s beliefs, claims and practices. It’s a way to justify one’s low standards of validation as being above challenge by logical argument or scientific evidence.

The third type of argument promoters of pseudoscientific and non-scientifically founded practices in the fitness, nutrition and health field will commonly use in attempt to defend their claims is by attacking the messenger. This attack is either directed at people, like myself, who promote taking a more science-based approach, or it’s directed at science.

Attacking the person who takes a more science-based approach is often expressed by them saying the individual is “negative” or “closed-minded.” Interestingly, many people have no trouble identifying someone like Dr. Oz for making big claims based on little to no quality scientific evidence. In fact, do so and you’re commonly considered by training, nutrition and rehabilitation professionals to be someone who means well because you’re trying to create more informed consumers. However, point out this same issue (i.e., making big claims based on little to no quality scientific evidence) about some “expert” in the fitness training, rehabilitation or nutrition field and you’re often considered someone who’s narrow minded and only cares about “hating” on others. This kind of blatant logical inconsistency is unprofessional; it’s beneath us, and it belongs at the kid’s table.

If they don’t attack the character of the person promoting the importance of providing scientific (objective) evidence to back up one’s objective claims, promoters of pseudoscience and fringe practices will direct their arguments towards science. Many people seem to think they’ve got the knock-down argument(s) against the entire scientific enterprise.

Below I’ve provided my direct responses to the most popular arguments against taking a more science-based approach to training and nutrition that I hear used by personal trainers, strength coaches and rehabilitation specialists in certain belief circles.

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1. “Trainers are ahead of research”

Here are the six most common flavors the “Trainers are ahead of research” line of argument comes in from trainers and coaches:

  • “Research follows practice, therefore trainers are ahead of research.”
  • “I’ve seen it work!” – “I don’t need to wait for science to tell me what I’m seeing work in practice.”
  • “I’m doing research by training clients and athletes – that’s real world research.”
  • “I value what the experts say over what the science says.” – “The experts wouldn’t be who they are if what they were doing didn’t work.”
  • “Lifters from back in the day relied on experience – they were ahead of science.”
  • “If I waited for research, I wouldn’t have been able to help my clients or athletes to (insert some type of physique or performance achievement).”

Since there is no more popular defense to the demand for taking a more science-based approach to training than appealing to the above lines of argument, I’ve already dedicated an entire article to Debunking the Top 6 “Trainers Are Ahead of Research” Arguments.

 

2. “It’s unrealistic to limit my programming to only published evidence”

Taking a more science-based approach to training does not mean that you won’t let your clients or athletes perform anything without a PubMed reference in hand – that’s a ridiculous straw man argument. As I said in my book Strength Training For Fat Loss:

“It’s great to use work-outs that have been evaluated in a study, but it’s unrealistic to ask that of every workout, especially when we’re changing workouts every few weeks to keep things fresh and interesting. Specific workouts don’t have to be scientifically studied as long as they are scientifically founded, meaning they are founded on the general principles that have been repeatedly shown to elicit the results you’re after.”

I think Dr. Jason Silvernail said it best:

“No one says you have to limit yourself to using just published evidence. You have to limit your claims to what you can defend with evidence, though.”

You see professionals like myself who promote a more science-based approach to training and nutrition are not discounting anecdotal claims as a whole, but discounting them in the context in which they are being provided. In that, what we take issue with is when people make objective (truth) claims based solely upon their subjective experiences. This is because the type of evidence they have provided (subjective) doesn’t warrant to the type of claim(s) they’ve made (objective).

Since ideas are only as good as the evidence that supports them, we should all want people to understand the difference between objective (i.e., matters of fact) and subjective reality (i.e., matters of personal taste), and seek to create a professional environment that demands intellectual honesty. There is no issue with people sharing their subjective experiences. Heck, I provide lots of anecdotal information in my articles, videos and workshops. Yet, none of my fellow promoters of a more science-based approach feel the need to “call me out” because I don’t give them a reason to do so.

Is it really too much to ask just be more humble and intellectually honest about the claims you make (and don’t make) by choosing your words carefully when communicating about your beliefs and practices, and avoid claiming to know things you don’t know?! This is all professionals who promote taking a more science-based approach to training, rehabilitation and nutrition keep trying to point out.

 

3. “The science must be wrong because I know what I see working in practice. And, I’m certainly not lying about what I’m seeing work.”

First off, you can’t “disprove” someone’s personal experience, which is why no one here is trying to do so. I have no reason not to believe that practitioners have had the experiences they’re sharing. The argument that comes from claims based on anecdotal evidence is with the explanation(s) someone provides as the cause of the experience they’ve had.

The fact that practitioners from every school of thought says they’re achieving the same types of results (e.g., pain relief, fixing “dysfunction”, improving performance, etc.), but make mutually contradictory claims about how to achieve these results reveals a deeper psychological reality that makes a mockery of all these “it works in practice, therefore it’s objectively real” based claims. And that reality is called Confirmation bias, which is a filter through which you see a reality that matches your expectations.

A note from the editor (Lawrence) – in addition to Nick’s fantastic article linked above, I’d also highly recommend this article from Aadam over at Physiqonomics on the subject of biases. If you’d rather get your education in audio form, I also recorded a podcast with Aadam in which we touched on confirmation biases – you can listen to that on iTunes by clicking here, or use the player below.

In other words, the goal isn’t to diminish people; it’s simple to help people recognize that there could be other possible (more likely) explanations for the experiences they’ve had. The mere fact that someone, or lots of people, had a certain type of experience in no way increases the likelihood that this experience is from the reason they say. And, we know this because of all the conflicting anecdotal evidence based claims in the training, rehabilitation and nutrition arena clearly demonstrate the fallibility of humans to accurately judge the evidence of our own experiences when it comes to things like health interventions.

That all said, if a practitioner only wants to go as far as to simply share that they’ve had an experience – that’s totally fine. However, when someone goes further and cites their anecdotal experiences (e.g., “it works for me”) in an attempt to 1) discredit science and 2) to convince others their beliefs and claims about the methods they use are objectively true, then that’s a big problem! We cannot simply decide such things on the basis of one individual’s experience for the realities described above along with those I’ve described here, here, here, here and here.

Put simply, without objective, corroborative evidence from other (outside) sources, 10 anecdotes are no better than one, and 100 anecdotes are no better than 10. Anecdotes are told by fallible human storytellers, which is why scientists have sayings like “the plural of anecdote is not data.” The most reliable means we have for determining which health interventions actually do work, and which ones are ineffective, but may still appear to work, is through scientific testing.

Don’t get it twisted! No one is saying that science is always right, nor is anyone saying that anecdotal experience isn’t important – it is! However, we must test our experience against the evidence – that’s what evidence-based practice is all about! And, when they don’t line up, the scientific evidence in no way makes the outcomes we’ve seen in our “in practice” experience any less real. It just means the conclusions practitioners are coming to based on their anecdotal experiences; it’s far more likely that the science is correct, and the practitioners have simply misinterpreted the evidence of their own experience.

 

4. “Those researchers don’t even look like they lift” – “Research isn’t real-world”

Statements about the physique or physical abilities of researchers are often said to imply that the scientific results of their work are somehow less valid. I don’t understand this reasoning because you’re supposed to be looking at the protocol they used and at the results the participants in the training or nutrition study got from it – not looking at the researchers who were there to observe and record data.

Many people mistakenly think that scientific testing isn’t “real world” because it’s often done under some type of control. “Controlled” doesn’t mean something robotic or artificial. It simply means, as Albert Einstein said about science, “a refinement of everyday thinking.” The scientific method allows us to use precise, objective specifications as to what constitutes success and failure. Without that our hopes and expectations can, and often do, lead us to detect more support for a given intervention than is actually warranted. It’s for this reality that observations gained by using controlled means (i.e., the scientific method) are far more reliable than those gained from using uncontrolled means (i.e., anecdotal experience).

In other words, scientific evidence, like many exercise and nutrition studies, is absolutely real-world, as it helps us to learn about how nature works by providing us with the evidence of reality. In fact, the conclusions drawn from using the scientific process are often more real world than the conclusion we come to when we let our intuitions and observations run unchecked and unexamined because those conclusions are clouded by our biases and preconceptions.

With this above in mind, as I said in my Science Vs. Coaches Vs. Athletes: Who Should You Listen To? article:

“Scientific evidence helps to tell us what’s reliable, but it doesn’t necessarily work well for telling us what’s practical on the training floor. On the flip side, anecdotal evidence helps to tell us what is practical on the training floor, but it doesn’t necessarily work well for telling us what is reliable.”

 

5. “You can’t challenge it until you’ve tried it” 

Claiming that someone is “not qualified” or can’t talk about a given health intervention, training or nutrition approach unless one utilizes the practice in question is essentially claiming that only believers can talk about the subject – thus eliminating all opposing views.

In other words, it’s basically saying those who do not believe the idea is true cannot criticize the idea, which is absolutely ridiculous. Claims about a given health intervention, training or nutrition approach aren’t just a question about the certain method being promoted; they’re also a question of human biology, physiology, etc. Those things are universal, and not proprietary.

Surely you don’t believe that the principles of human physiology, anatomy, etc. cease to exist in the presence of any type of health intervention, training or nutritional approach?!

 

6. “Science doesn’t have all of the answers.”

The scientific method is the best tool we have for objectively determining which claims are true and which are false (or at least offering probabilities of the likelihood of a claim being true or false). That said, I don’t think science has “all” the answers. When it comes to testable (objective) claims and learning about nature, I do think science has the “best” answers, however provisional they may be.

There are lots of areas of genuine scientific uncertainty and ignorance. The way to clarify this domain is not to pretend to know things that you don’t know. Not to mention, the lack of a strong scientific answer doesn’t make your answer any more likely to be correct. And, it certainly doesn’t mean that every answer is just as good as any other.

“When two opposite points of view are expressed with equal intensity, the truth does not necessarily lie exactly halfway between them. It is possible for one side to be simply wrong.”– Richard Dawkins

The stance of science when something is not fully understood is that it is not fully understood. The stance of superstition and pseudoscience is that if something isn’t fully understood, it should be attributed to a non-falsifiable hypothesis like “qi” or ancestral spirits — in other words, flying spaghetti monsters-ism.

Put simply, you can’t answer a mystery with another mystery and provide anything of practical value. Sure, anything is possible, but what’s more probable? I’m too much of a skeptic to deny the possibility of anything, but I don’t see my way to your conclusion if it’s based on what’s possible instead of what’s most probable.

 

7. “First science said eggs were bad, then good, then bad…”

This argument is based on media headlines and “talk-show science.” And, the bias of the majority of mainstream media is toward sensationalism.

In the mainstream media there is a lot of B.S. masquerading as (good) science. However, scientists know not to place too much significance in single (preliminary) studies – the kinds of which the media loves to talk about – until they’re placed it in a much larger context of all the related research.

“Often times a small study with nuanced, tentative findings gets blown way out of proportion when it’s summarized to us in the press.” — John Oliver

“I’ve noticed that the press tends to be quite accurate, except when they’re writing on a subject I know something about.” — Keith F. Lynch

Put simply, although what we see in the mainstream media has some people thinking that science is B.S., this is a highly flawed perspective because the mainstream media doesn’t usually represent the entire scientific enterprise or the current scientific consensus on a given topic.

That said, scientific answers have changed on many subjects and will continue to do so. These (provisional) answers have gotten more precise as we’ve gotten additional information. That’s called learning!

Interestingly, when training, nutrition and rehabilitation trends change, we call that professional growth, but when it happens in science many people view that as science not knowing what it’s doing. The difference is scientific progress creates real progress, while many of the changes in training, nutrition and rehabilitation trends are phony collective progress because the trends change but the big claims stay the same. The new best thing is better than the last new best thing.

What should strike you in the area of training, rehabilitation and nutrition education is a history of false dawns. Professionals in these fields are always being told, “this is it,” “now we’ve found this powerful method” – “the missing piece.” All of these once “this is it” methods sounded amazing and came with cool demonstrations when they were being taught to us. And, they also created lots of passionate and intelligent practitioners who claimed they had great success using these ideas. Yet, over time, somehow those practices just seem to all peter-out and people lost interest… only to become yet again caught up with the current “this is it” thing – ensuring that history keeps repeating itself.

Each prior generation of smart, well-meaning training, rehabilitation and nutrition professionals were being guided by information provided in courses just like the ones we have today – information which is now deemed to be highly incomplete and mistaken – using these very same reasons  (e.g., “it works in-practice”) to justify the information they were providing. This undeniable reality demonstrates that people can absolutely teach courses all over the world, and become recognized names, despite the fact that the information they’re teaching is incomplete and erroneous.

In other words, despite the fact that theses professional educational courses were teaching flawed information, they were still able to convince many well-educated and passionate practitioners (just like you and I) that it was valid information.

The reality that we must learn from this pattern is that just because something is currently a “hot topic” among “experts” in certain belief circles, sounds convincing and has lots of passionate practitioners sharing their anecdotes, in no way speaks to the validity of the claims made about any given training concepts or techniques. And, the reason why this pattern keeps getting repeated is because anecdotal thinking comes naturally but skeptical and scientific thinking takes training.

It’s human nature to think correlation equals cause/effect. Science makes observations and reaches possible, tentative insights that become a hypothesis that attempt to be falsified. On the other hand, pseudoscience often stops at *observations* and takes it as ‘proof’ of their conclusion. Pseudoscience promoters begin with a belief then find ways to make that approach seem scientific.

In short, human nature wants instant answers but the scientific method requires patience. So, pseudoscience appeals to our human nature by supplying a quick answer, usually based on small sample sizes and seldom accounting for the powerful placebo effect. Like candy, it’s tasty but empty. That is, in most cases, as the blind squirrel will occasionally find a nut.

 

8. “Science can be wrong” – “Research can be biased” – “Follow the money”

You can certainly pick out individual scientists, or individual theories or individual moments in science where scientists were just flat out wrong based on their own biases. That is a totally legitimate thing to do. It’s a totally scientific thing to do!

What separates the scientific process from anecdotal experience is that it seeks to remove the subjectivity component from observations. Sure – like you and I, individual researchers are subjectively biased, but the scientific method is not biased in that manner. It’s an objective process that has built in machinery that teases out individual bias and bad science.

You see, bias in science is bad science, but bias in certain training, rehabilitation and nutrition belief circles is dogma. You don’t have the same corrective mechanism in belief circles. These following words from The Skeptic’s Society summarize things perfectly:

“Eager to discredit science, many pseudo-scientists cherry pick examples of mistakes in the belief that mistakes in science are a sign of weakness. This is a gross misunderstanding of the nature of science, which constantly advances by using both its mistakes and the successes. Its ability to build cumulatively on the past is how science progresses. The self-correcting feature of the scientific method is one of its most powerful assets. In fact, it wasn’t these people who exposed these errors; it was scientists who did so. These people simply read about the scientific exposé of these errors, and then duplicitously claimed them as their own.”

Additionally, my favorite skeptical author, Guy P. Harrison has already addressed the issue of the influence of financial interests better than I ever could. Although his following words focus on the medical side of things, they also perfectly apply to the training, rehabilitation and nutrition arena:

“Some ‘tested and proven’ medicines are not tested properly or well enough, are not prescribe safely, or were compromised by incompetence or profit/ ethics issues and end up causing more problems than they solve. Every year, tens of thousands of people are injured or die of complications from evidence-based, tested, and regulated drugs and treatments. But this is NOT a sensible reason to reject medical science and turn to pseudoscientific practices like Complementary and Alternative Medicine (CAM). If anything, I would hope that one would view the very serious problems with modern medical science as only more reason to avoid the largely unregulated and fraud-riddled world pseudoscience like CAM. If we can’t even trust tested, regulated, and scientific health treatments all the time, why would anyone choose to risk his or her safety with untested, unregulated, and pseudoscientific health treatments?

It should be no surprise that medical science and mainstream health care fall far short of perfection. How could it not with humans involved? What is important to understand, however, is that there is at least a good chance, a reasonable hope, that a particular drug or treatment on the evidence-based side of healthcare was produced by a process based on science, was tested, and is more likely to be safe and effective. Across the border, over in the land of alternative medicine, the risks of a treatment being ineffective or dangerous skyrocket because anything goes. I wouldn’t want to drive a car or eat a candy bar that wasn’t tested and regulated in some way. I certainly don’t want to put untested and unregulated medicine into my body when I’m sick. Yet millions of people are willing to trust mysterious pills and potions that could have just about anything in them and do just about anything to the human body.

The mystery for me in this is why anyone who finds it difficult to trust the for-profit evidence-based medical industry would run into the open arms of the for-profit unscientific CAM industry. They are big business and they care a lot a whole lot about profits too! (Note: According to a national health statistics report, $33.9 billion was spent on CAM in 2007.) Given the frauds, dubious claims, and dishonest advertising that is rampant in the alternative healthcare industry, why in the world would anyone trust them more than evidence-based healthcare?”

 

9. “They didn’t study the people that I work with”

You’re right! And, neither did the studies looking at the adverse health effects of tobacco use (i.e., smoking), nor did any of the studies done on the wide ranging health benefits of regular exercise and/or better nutritional habits. Certainly you don’t think it’s reasonable for one of your clients, athletes or patients to reject your advice to avoid smoking, or to improve their eating habits, or to exercise more regularly on the basis that “those studies weren’t done on them.” Surely you don’t actually believe that studies have no relevance to anyone else except for those who actually participated in the study(s)?

There is genetic variation in everything from human skeletal structure to individual response to exercise to the health impacts of smoking. That’s precisely why health organizations don’t say that science has shown that tobacco use causes cancer; they say that tobacco use greatly increases your risk of developing cancer (and dying from it). So, the fact that your grandfather smoked until he was 95 years doesn’t disprove the general health recommendations on tobacco use. And, the fact that there is generic variation in response to exercise doesn’t disprove the general relevance of studies looking at everything thing from exercise to back pain to nutrition to medicine and health.

 

10. “There’s more to life than evidence” – “It’s your truth vs. my truth”

How would you go about demonstrating that there is more to life than evidence without providing any evidence? You see – it always comes down to evidence.

Although many people try to bring up “love” as the exception to this – Love expressed towards someone without evidence of them loving you back is stalking. (I stole that one from Tim Minchin.)

In regards to “Your truth vs. my truth”: my objection here is with objective and subjective reality (i.e., truth). In that, the problem with personal (subjective) experiences is that people try to take an internal experience to explain an external (objective) reality.

Put simply, your feeling of something only makes it true in terms of matters of taste. Your feeling of something doesn’t make it true in terms of the (objective) reality that we all share. When it comes to matters of your own personal taste, you’re infallible. However, when it comes to coming to conclusions about matters of objective reality, we’re all highly fallible due to the many different cognitive illusions, failings of intuition, and inherent biases in the data upon which we base our beliefs, which you’ll learn more about by reading books like How We Know What Isn’t So. 

I’ve realized that one of the main reasons why so many smart, well-meaning fitness, rehabilitation and nutrition professionals attempt to present their anecdotes as “proof,” even in the face of contradictory scientific evidence, is because they’re unaware of the innate fallibility of human reason and judgment in everyday life. When one doesn’t know about these realities, it’s very easy for one to overvalue the conclusions they and their colleagues have drawn from their own “in-practice” experiences. However, when one does become of aware of these realities, if one values truth and reality, one embraces the fact that it’s not safe to let our intuitions and observations run unchecked and unexamined. It’s in our best interest to test our experiences against the scientific evidence. And, when they are tested and fail, it makes it even more likely that the science is correct, and our cognitive processes have caused us to misjudge the evidence of our own experience – Cognitive processes that skepticism, and the methods of science and statistics grew up specifically in opposition to.

What usually separates skeptics and people who a more science-based approach from those who believe in fringe health practices more than anything else is a thorough knowledge of the mechanisms of self deception – the basic flaws in our reasoning apparatus that lead us to see patterns and connections in the world around us, that upon closer inspection reveals that in fact, there are none. And, that’s precisely the reason why I recommend books like You’re Not So Smart, why I was inspired to put together my Why Smart Trainers Believe Stupid Things series. It’s to help you become a better skeptic, to empower you with the know-how to think more clearly by being better able to recognize and work to overcome the variety of innate cognitive mechanisms that cause our thinking to go wrong.

 

Final Words

Before I wrap up this article, it’s important to note that with many of the people who use the arguments against science that I’ve addressed above, it’s their denial of the scientific evidence that’s often the preface to their justification for their belief in pseudoscience and non-science.

This line reasoning is faulty because, even if we threw out all of the relevant scientific evidence on a given training or nutrition topic today, it still would not put us even one-step closer to any of their claims being (objectively) true anymore than airplane crashes validate the truth of flying carpets. That’s why, when these types of arguments against science are used to justify one’s belief (e.g., science is wrong, therefore I’m right), which is often how they’re being used, it does absolutely nothing but demonstrate one’s lack of ability to provide positive evidence in favor of their claim(s).

As I said in my 6 Negative Thinking Strategies for Positive B.S. Detection article:

“In order for something to successfully reject the null hypothesis, and therefore warrant (provisional) belief that a claim is (likely to be) true, one must provide positive evidence in favor of their claim, not simply provide negative evidence against something else.”

Now, just because many people use these arguments in the flawed manner I’ve just described does not mean than everyone who uses these arguments does so in this manner. So it would be unfair and inaccurate to simply dismiss these arguments on that basis alone every time they’re brought up. To some people the arguments I’ve addressed in this article are simply expressing concerns they have with science, and therefore why they’re reluctant to look at scientific evidence as a reliable means of coming to learn/know (objective) reality. And rightfully so – science certainly isn’t without its mistakes and biased results.

My purpose, and my challenge, in addressing this list of arguments I see many of my fellow health and fitness professionals commonly using against taking a more science-based approach to training, rehabilitation and nutrition is to help separate the valid concerns about science (and a potential solution to those concerns) from the arguments that are based on logically flawed thought processes, confusion and misunderstanding, or downright ignorance and nonsense. I hope I was able to, at least to some degree, accomplish that task and meet that challenge in this article.