Introduction to the special edition on the placebo effect in sport and exercise

The placebo effect has been studied in medicine, psychology and neuroscience for well over 50 years. Whilst it remains controversial in many respects, it is now widely accepted as a real neurobiological effect. Given the strong association with medicine, we should perhaps not be surprised – especially in light of the rapid growth of sports medicine and of the idea of exercise as medicine – that researchers in sport and exercise have also shown interest in the placebo effect. As is demonstrated in the review paper by Hurst, Schiphof-Godart and colleagues in this edition, the published literature in sport supports the proposition that the placebo effect has the potential to influence performance. Likewise, Lindheimer's two contributions, following up on his earlier meta-analysis (Lindheimer, O’Connor, & Dishman, 2015) which demonstrated that a significant percentage of the effects of exercise on psychological outcomes is placebo, reinforce a similar if arguably less researched idea in exercise. In short, we can now be confident is saying that the placebo effect is a factor in sport and exercise.

In writing the papers in this special edition, the authors from Belgium, Hungary, Italy, the Netherlands, UK, and USA, believe that the study of placebo effects now needs to move beyond description of the phenomenon, and should seek to identify antecedents, mechanisms, and outcomes in a more systematic manner, an idea we first promoted in this journal in 2018 (Beedie et al., 2018). A reasonable question might be to ask why this is important. We believe that the answer breaks down into two parts: firstly, by understanding the placebo effect we will better understand the interactions between the minds, brains and bodies of athletes and exercisers, which of course must be one of the main objectives of the sport and exercise sciences. Second, by better understanding the placebo effect (and the nocebo effect) in sport and exercise, we might be better able to evaluate and optimise interventions in research and practice, and in doing perhaps help practitioners, athletes and exercisers make more informed choices.

Of course, a challenge in setting out to achieve the above is to satisfactorily define the placebo effect in the first place. Raglin and Szabo's paper makes a significant contribution in this respect, placing the definition firmly in the sport and exercise context. In doing so it will help future researchers better operationalise and investigate the effect.

A further aim of the special edition, over and above adopting a multi-disciplinary approach from within the sport and exercise sciences, was to integrate ideas from other fields. Contributions from Benedetti, Barbiani and Camerone who have conducted ground breaking research on the placebo effect in neuroscience (Benedetti, Barbiani, & Camerone, 2018), as well as from Davis who with colleagues has done the same in cognitive anthropology (Davis & Cohen, 2018), introduce novel ideas and approaches that might be pursued by sports and exercise scientists.

The papers in this special edition represent – to paraphrase an often cited statement – not the end of the story of the placebo effect in sport and exercise, not even the beginning of the end of that story, but we believe the end of the beginning! We look forward to seeing research into the placebo and nocebo effect making a significant contribution to knowledge and practice in the sport and exercise sciences over coming years.

Disclosure statement

No potential conflict of interest was reported by the author(s).

ORCID

Chris Beedie http://orcid.org/0000-0003-0106-3479

Florentina Hettinga http://orcid.org/0000-0002-7027-8126