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  • Writer's pictureJo Clubb

Why we should believe in belief effects in sports performance

This post was inspired by a recent thread by Altis CEO Stuart McMillan. In his discussion on coaching, communication, and building buy-in, Coach McMillan stated a view on athlete beliefs that many share:

Anecdotally, buy-in is powerful. Belief, in the coach, programme, game plan, and themselves, appears to help athletes reach another level. In that discussion, Coach McMillan contends that the athlete’s belief probably supersedes the actual quality of the work they do.

Performance is of course complex, yet there is empirical evidence to support the paradigm of belief effects. In this post, I’ll discuss some of this research, starting with a surprising source; hotel cleaning maids…

Beliefs influence the body’s response

Harvard University Drs Crum and Langer (2007) demonstrated an improvement in health outcomes in hotel room attendants, compared to controls, after a single education intervention. Those in the intervention group were told that their work (cleaning rooms) is good exercise and satisfies the criteria for an active lifestyle.

Four week later, despite no changes in behaviour, improved measures of weight, blood pressure, body fat, waist-to-hip ratio, and body mass index were observed. The improvements in health outcomes seemed to be driven by a change in beliefs that their day-job provided exercise.

That warrants repeating; outcomes seemed to be driven by a change in beliefs.

Further work by Dr Crum has shown that mind-set can affect the physiological response to food. For instance, there was a divergent response of ghrelin (known commonly as the “hunger hormone”) to the same 380-calorie milkshake, marketed on different occasions as a 620-calorie “indulgent” shake versus a 140-calorie “sensible” shake (Crum et al., 2011). The mind's expectation drove a different physiological response to the same drink.

Similarly, this week Dr Sian Allen shared (right) an article from Nature (Park et al., 2020) also demonstrating glucose metabolism responds to perceived sugar intake more than actual sugar intake.

Evidently, the body’s physiological response is influenced by what the mind believes it is doing or consuming. For those interested in exploring further, I recommend Dr Crum’s TED talk or episode on the Huberman podcast.

What about athletes?

When we think about belief effects, we might think about the placebo effect. Placebo effects from inert treatments on sports performance are well documented (Beedie et al., 2006; Clark et al., 2000; McClung and Collins, 2007; Beedie and Hettinga, 2020). So belief in a supposedly performance-enhancing intervention, particularly novel ones, can improve performance regardless of real treatment effects (Halson and Martin, 2013).

But the motivation for this post was not to explore physical placebos, but belief in a program. This relates to the social cues and environmental influence. On this topic, Arran Davis presented in the European Journal of Sports Science:

“You don't need to administer a placebo to elicit a placebo effect: Social factors trigger neurobiological pathways to enhance sports performance”

The environment itself can act as a placebo that enhances, or diminishes (nocebo effect), performance. Consider one of the examples discussed in Davis’s review: 17 individuals broke the 4-minute mile within five years of Roger Bannister first breaking the invisible performance ceiling. Were physical outcomes driven by a change in belief via social facilitation that it was an achievable feat?

Or the study that found improved anaerobic performance in a rugby team following a synchronised warm-up, compared to a non-synchronised warm-up (Davis et al., 2015). Humans are social creatures and our environment influences our performance.

All practitioners should think like psychologists

Beedie and colleagues (2015) contend there is overlap between sports practitioners and applied psychologists, given that they are both interested in behaviour change (notwithstanding the need for specialist, licensed psychology professionals). It is often the underlying beliefs that can be modified to promote behaviours that support performance improvements. It follows then that we should all think like psychologists.

Practitioners may influence social belief effects explicitly via the information they provide to the athlete, or implicitly via the athlete’s perception of the practitioner’s credibility and/or expertise (Davis et al., 2019). So yes, as Coach McMillan reflected in his thread, it is critical for coaches to consider “what do I need to do, how do I need to communicate – to ensure that the athlete believes maximally in him or herself, their ability, their team, their program, and me, as their coach?

Our language matters. Every aspect of intervention administration can moderate the belief effect. So much so that sports practitioners have been encouraged to “inject words (not drugs) to improve performance” (Roelands and Hurst, 2020).

Promoting belief effects as a skill

While more research is needed, promoting beliefs in an intervention or the programme as a whole may have tangible effects on adaptation and performance. As such, the coach-athlete relationship is a critical element to enhancing (or diminishing) belief effects.

We can seek to intentionally capitalise (ethically) on such belief effects. Perhaps this ability is itself a measure of practitioner effectiveness.

So while it may be seen as a cliché, promoting beliefs is another approach in the coaches’ toolbox that deserves intentional and measured use.


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