One may assume that the mental strength displayed by athletes and high performers in general makes them less susceptible to the placebo effect. This could not be further from the truth, particularly given the multifactorial and difficult to pin down nature of what goes into high performance. As many as 73% of international and professional athletes surveyed suggest they have experienced the placebo effect.
The researchers in this study, grouped responses of athletes’ stories of the placebo effect into four groups:
1) Explicit placebo effects, that is effects resulting from a false belief deliberately propagated by a third party
2) Inadvertent false belief, that is an effect resulting from accidental misinformation either by a third party or by the athlete themselves
3) Ritual, that is, effects related to the customary behaviours of an individual or a sport
4) Reverse placebo effects, that is the realisation that a substance or technique now discontinued was in fact exerting its influence via a placebo effect
This texture probably speaks to the ubiquity of placebo in the world of sport and performance, where the ethics of placebos are a little less challenging than they may be in the health field.
There are many routes we could take to explore ‘placebo’ in training and exercise. We could discuss things which are very classically associated with placebos like supplements. Alternatively we could explore deception and it’s role in performance or even factors like hydration. This is not to mention things like the role of things such as belief and sociocultural factors in performance and coaching, all of which may fall under the umbrella of what folks call “The Placebo Effect”.
Note this is part two of a series on the placebo effect, if you haven’t read part one; check it out here (and subscribe above so you don’t miss another).
Supplements
We should probably start with the most effective performance enhancing supplement and world’s most abused drug: caffeine. For the record it’s also the one most of the placebo research has been done on.
One challenge in research is creating appropriate placebos, because at the heart of the placebo effect is the belief that one is receiving something that isn’t a placebo (see part one linked above where I discussed the impact of incorrectly labelling the active drug as a placebo and many other permutations of similar mislabeling). This seems fairly straight forward in the setting of caffeine, after all, decaf exists. That said there are a few problems with using decaf; it has some caffeine (albeit a negligible amount) and probably most significant, as I found out in my undergraduate when we tested caffeine vs placebo (via coffee) in my exercise physiology course; people can often tell.
A Quick Word on Coffee vs Caffeine
Coffee is more than a caffeine delivery method, it can be full of polyphenols and other healthy components. These are things caffeine certainly does not have. Likewise, caffeine itself is quite bitter as anyone who’s used caffeine gum can attest to. This too can pose a problem for placebo studies at times, though it does come in pill form (perhaps the easiest form to use caffeine in scientifically all things considered).
Coffee itself, can have varying caffeine levels, specifically impacted by dose of coffee beans, extraction time and brew method of the coffee and then some aspects climatic differences and of course the beans themselves and how they are roasted. All of this said, bitterness of coffee isn’t solely related to caffeine (in fact the easiest way to make bitter coffee is over roast or over extract). All of this is why the term “strong” with respect to coffee is a minefield and why using coffee in research studies is probably ill advised if caffeine is what’s in question.
So Does Caffeine Work? Or is it just Placebo?
Historically, caffeine has been one of the easiest supplements to recommend for performance enhancement in any realm of performance (strength, endurance, skill, mental performance etc). That said, as discussed in this article, group effects do not apply to all individuals in that group and as we are learning more and more, dissecting the nuance, we are learning caffeine’s impact on performance is not uniform (in somewhat of a ‘meta’ phenomenon this speaks to what I hope for the placebo effect - we start to tease out the nuance and understand it better). It looks like genetics may play a role in caffeine’s impact (or lack thereof) in some people, though this is by no means ‘settled’.
There is a not insignificant body of research suggesting that much if not all of the effects of caffeine is as a result of the placebo effect. There is nuance here, however, in that some of the research design may not be appropriate to elicit caffeine’s benefits - here we find ourselves in a situation where science evolves and teases out the fact that initial study designs (the ones that caused me to say things like; ‘caffeine looks to help everyone for everything except sleep’) may not have been appropriate. So we are evolving our understanding of caffeine in parallel to better understanding the power of placebo. Caffeine’s most robust research is in the endurance and mental performance under sleep deprivation spaces.
That said, most fellow ‘caffiends’ in the readership would agree, that you certainly feel more able to do the things once you’ve had the coffee, whatever ‘the things’ are.
For the record, the research doesn’t support the need for weaning off caffeine for maximal performance benefits (though athletes anecdotally seem to find this helpful for wakening effects). Likewise, caffeine has some diuretic (water losing) effects, but these are usually offset by coingestion of fluid (as is the case with coffee, energy drinks etc).
One particularly interesting study, looked at the impact of placebo on performance (the details aren’t super important, though the paper is in the reference list if you’re so inclined) and found that intention to use supplements improved performance when taking a placebo. This was in the case that individuals were told their placebo would aid performance OR detriment it (the so-called ‘nocebo effect’). This speaks to the role expectation and beliefs play in the placebo effect.
Hydration
We’ve all heard the statement “if you wait till you’re thirsty, you’re already dehydrated”, and of course we know that any amount of dehydration impairs performance. Without going in on ‘big sports drink’ or ‘big water’ I’d urge you to read this article I wrote about the body as a robust and adaptable organism. Suffice to say, we are a little more robust that having plummeting performance when the first bit of thirst arrives.
Interestingly when it comes to hydration, we see a pattern that seems to repeat quite often in performance. In short, a physiological situation (low carbohydrate availability, dehydration etc) looks to be a consequence of the perception of this situation such that the performance impact can be mitigated through deception. This is sometimes called ‘the central governor’ though as often the case in science, there’s debate about concepts and names. But the summary is, something in the mind prevents us from performing because we are nearing some physiological situation that may be dangerous to us (aka self preservation). To this end, there are some really smart and fascinating studies into hydration where subjects are dehydrated before some very smart science. These subjects then either drink or not, and some of these folks have the water removed from their stomach via a nasogastric tube (a tube through the nose down into the stomach - it’s as unpleasant as it sounds) whilst others have water added to the stomach via the nasogastric tube. The result is four groups; one drank, one drank & had the water removed, one had water inserted into their stomach and one did not. Those who drank seemed to avoid the performance decrement of dehydration, speaking to the role of drinking itself. Of course, this isn’t to say dehydration plays absolutely no role in performance, but again - there’s nuance.
This pattern certainly seems to be born out somewhat consistently in the carbohydrate space too. A carbohydrate “mouth rinse” is accepted to improve performance in shorter duration (~30mins) endurance events. Similarly recent evidence has shown this to improve Romanian deadlift performance also.
Conditioning
As mentioned above, there seems to be a central (mind) role for the placebo effect, which fits with the discussion in the previous article in this series (linked above) talking about placebos in the health space. There certainly looks to be a higher susceptibility to placebos when there is a larger contribution of the mind, which looks to be the case in fatigue. Similarly, as discussed in that piece, there is a significant role of expectation and conditioning, which looks to be born our in the performance literature also.
How Big is the Placebo Effect in Performance?
Placebos and Steroids
In an interesting study that would probably not receive ethical approval in 2024, Ariel & Saville tested the placebo effect of anabolic steroids (in 1972). Of note, the sample size was painfully small event for sports science literature but none the less the results are fascinating!
Crucially the subjects underwent training to track their progress before the study started, acting as a natural control for themselves (remembering the talk of natural course of disease in part 1 of this series - this is similar in that you’d naturally anticipate some improvement with training, regardless of placebo or active intervention). They were then given a placebo and told it they were taking anabolic steroids. They improved 3.4%, 0.8%, 2.7% and 2.0% for bench press, military press, seated press and squat, respectively during their training period prior to taking anything (control). Whereas they improve 9.6%, 8.5%, 6.2% and 13.8%, respectively when told they were taking steroids.
*Note they were taking pills, there is certainly some suggestion that if they’d taken (even more ethically dubious) placebo injections they would have improved even more! Remember, part of this is about expectation and most people expect injections to work better than pills.
To move the ball forward slightly, Maganaris and colleagues did a similar study in the year 2000. In this case though, they gave all subjects placebo steroids - which worked well. Then, before retesting, informed half of the subjects that their ‘steroids’ were placebo and subsequently these folks regressed back to baseline, and some performed slightly worse, whilst those who thought they were taking steroids maintained their improved performance.
Other Placebos
Having already touched on one extreme, that of anabolic steroids and the magnitude of the placebo effect there and caffeine, where the effect is smaller but still quite significant it bears examining other substances.
Unsurprisingly, or perhaps, in fitting with expectations of the placebo effect, it is more significant when the intervention is more significant. For example injectable placebos exert stronger effects than oral placebos. In sports performance, nutritional placebos have the weakest (but still present) effect, similar to mechanical placebos. As mentioned moderate effects were seen for caffeine and similarly amino acids and modified tennis rackets. The aforementioned large effects for anabolic steroids were seen with EPO and Transcutaneous Nerve Stimulation (TENS).
It should be noted that the review that quantified all of these also found a significant effect of pre-conditioning on the efficacy of the placebo effect. This speaks to expectation, in short; telling you how good a new supplement is and then giving it to you works better than just giving it to you.
What about Nocebo in Performance?
You bet your bottom dollar this exists. Given how fickle performance can be, it’s not unlikely we see much more nocebo than placebo in the performance realm.
An interesting example of the nocebo I was thinking about a little while ago is Loftus Versfeld rugby stadium in Pretoria, South Africa. There seems to be a few grounds in the world of rugby which prove to be fortresses, where home teams lose few matches and this is certainly one of them. The South African national team aka the “Springboks” lose very few matches there and if you ask people why you will get a variety of answers but many will point to the altitude (1350m/4430ft). Opposition will even say that they struggle with the altitude. All of that said, currently very few Springboks live in Pretoria and/or play for the team there, nor do they live in Johannesburg (which is even higher at 1753m or 5751ft). Perhaps there’s more psychology or psychobiology at play than pure physiology.
Take Aways
Placebo in the realm of performance conforms to many similar patterns, including being more prevalent in areas with more impact of the mind.
The more significant the perception of an intervention the greater the performance improvement.
The vast majority of athletes have experienced the placebo effect.
When it comes to ethics, the performance realm is much less concerning than the realm of health. Many would agree that belief, perhaps as a result of placebo, is not abnormal and perhaps even part of the role of the coach.
Ps if you this piece piqued your interest and you want some more of how the mind can impact performance, Endure by Alex Hutchinson is a must read. One that’s a little more athlete focussed than focussed on learning is How Bad Do You Want It by Matt Fitzgerald (warning, you may be inspired to go run through a brick wall afterwards, or at least up a big hill repeatedly).
References
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