Expectancy Effects and Strength Training: Do Steroids Make a Difference?

Article (PDF Available)inSport Psychologist 14(Pt 3) · November 1999with 3,155 Reads 
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DOI: 10.1123/tsp.14.3.272
Cite this publication
Abstract
Full-text of this article is not available in this e-prints service. This article was originally published following peer-review in Sport psychologist, published by and copyright Human Kinetics. Although expectancy has been shown to play a role in the effect of Anabolic Steroids (AS) on behavior, little research has been completed on the potential for parallel effects on performance. This is an important area for investigation because if expectancy effects can be shown to operate by improvements in performance through the administration of a placebo, arguments against the use of AS may be more successfully advanced. Accordingly, the present investigation used the administration of a placebo (saccharine) with competitive power lifters, using false information about the nature of the drug to delineate expectancy effects. The pervasiveness of these effects was further examined by disclosing the true nature of the drug to half of the participants, midway through the investigation. Notable improvements in performance associated with the belief that AS had been administered largely dissipated when athletes were informed as to the true nature of the drug. Results indicated that expectancy played a notable role in performance enhancement. Implications for this work include more effective use of such investigations in the fight against doping in sport.
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  • ... A placebo is a pharmacologically inert substance that, despite chemical inactivity, can impact the body. 1 Placebos have helped reduce doses of attention deficit hyperactivity syndrome medication, relieve pain 2 , and reduce irritable bowel syndrome symptoms 3 . With regard to exercise performance, placebos have improved laboratory-assessed performance in running 4 , cycling 5,6 , and strength activities 7,8 . For a review on the topic of the effects of placebos in sports performance, see Beedie, et al. 9 The ability of placebos to reduce physical pain may be the mechanism by which placebos improving exercise performance may function. ...
    ... We did not specific a type of supplement or how it could increase performance as other studies have done. 7,8,21 Previous work in highly trained subjects has found strength improvements following placebo supplementation when subjects thought they were taking steroids. 7,8 Other work has found strength improvements in college students when they thought they were taking amino acids 17 , and caffeine 16 . ...
    ... 7,8,21 Previous work in highly trained subjects has found strength improvements following placebo supplementation when subjects thought they were taking steroids. 7,8 Other work has found strength improvements in college students when they thought they were taking amino acids 17 , and caffeine 16 . Thus, it is possible that had we told subjects our placebo was one of these substances, we may have seen different results. ...
    Article
    Objectives: The purpose of this study was to examine the effects of both known (“honest”) and unknown (“dishonest”) placebo ingestion on VO2peak to see if placebo ingestion would influence the test outcome by influencing the psychological compo nent of this test. A secondary purpose was to examine these effects on isometric handgrip strength. We hypothesized that placebo (honest or dishonest) ingestion prior to a VO2peak test would increase VO2peak compared to a control condition. We further hypothesized that isometric handgrip strength would be greater during both conditions of acute placebo ingestion compared to a control condition. Design: In a randomized, cross-over, counterbalanced design, subjects performed three trials: exercise tests with honest place bo, exercise tests with dishonest placebo, exercise tests only (control condition). Method: 41 subjects (28 males) aged 24 ± 7 years were tested. RM ANOVAs (3 × 1) were used to analyze VO2peak and handgrip strength across conditions. RM ANOVAs (3 × 1) were used to determine if test order influenced VO2peak and handgrip strength. (Alpha = 0.05.)Results: No differences were found across conditions for either VO2peak (p = 0.360) or handgrip strength (p = 0.474). Further, no differences were found for trial order for either VO2peak (p = 0.766) or handgrip strength (p = 0.067). Conclusions: Administration of both an honest and a dishonest placebo immediately prior to VO2peak and handgrip testing resulted in no differences in performance compared to each other or a control trial. The VO2peak test is a robust exercise test not influenced by immediately-prior pre-workout supplement consumption.
  • ... These significant improvements were impressive given the study's small sample size and the advanced training level of the participants. Nearly 3 decades later, Maganaris et al. (2000) performed a similar study, but in addition to analyzing improvements in performance with perceived steroid use, the authors examined the potential decline in the participants' performance after learning that they were actually using a placebo. When the participants were told that they were receiving anabolic steroids, significant improvements in bench press, squat, and deadlift strength were found. ...
    ... Placebo and OLP treatments have shown promise in enhancing muscular performance in athletes (Ariel and Saville 1972;Maganaris et al. 2000;McClung and Collins 2007;Beedie and Foad 2009) and improving patient outcomes in clinical settings (Sandler and Bodfish 2008;Kaptchuk et al. 2010;Kelley et al. 2012;Carvalho et al. 2016;Hoenemeyer et al. 2018), respectively. We tested the hypothesis that, in untrained adults, placebo and OLP treatments would enhance muscle strength and minimize neuromuscular fatigue. ...
    ... The obvious difference between these types of studies is that patient populations with chronic conditions likely enter into a study hopeful that a given intervention will be helpful in relieving specific symptoms, whereas our participants were college-aged and unaccustomed to rigorous exercise but healthy, nonetheless. In addition to patients, our study's participant population differed from many other placebo interventions that have studied athletes (Maganaris et al. 2000;McClung and Collins 2007;Beedie and Foad 2009). It is not inconceivable to suspect that personality characteristics and motivation levels differ among well-trained athletes and the participants in the present study. ...
    Article
    Purpose Recent evidence suggests that deception may not be necessary for placebos to improve clinical outcomes. We tested the hypothesis that placebo and open-label placebo (OLP) treatments would acutely improve strength and voluntary activation, as well as minimize neuromuscular fatigue, in untrained participants. Methods Twenty-one males (n = 11) and females (n = 10) visited the laboratory on three occasions (placebo, OLP, control) to receive each treatment in a randomized, counter-balanced manner. Trials involved a pretest, a 15-min intervention, and posttests. For the placebo trial, participants were informed that they would be ingesting a capsule that would improve their performance and make them feel more energetic. For the OLP intervention, participants were told that the capsules would have no effects. In “Experiment #1”, knee extensor maximal voluntary contraction (MVC) peak torque and percent voluntary activation were evaluated. In “Experiment #2”, participants performed 20 consecutive MVCs while surface electromyographic signals were detected from the vastus lateralis. Subjective assessments of energy and perceived exertion were examined. Results The interventions had no effect on strength or voluntary activation, but energy levels increased following treatments (p = 0.016, η² = 0.257). Neither treatment influenced neuromuscular fatigue. Though some variables showed moderate-to-large effect sizes, these results were consistent for individuals with lower voluntary activation. Conclusion Placebo and OLP treatments had minimal influence on strength, voluntary activation, and fatigue resistance. As these findings differ from recent reports, we speculate that placebos and OLPs are more likely to enhance muscle function in patient populations seeking medical care.
  • ... These significant improvements were impressive given the study's small sample size and the advanced training level of the participants. Nearly 3 decades later, Maganaris et al. (2000) performed a similar study, but in addition to analyzing improvements in performance with perceived steroid use, the authors examined the potential decline in the participants' performance after learning that they were actually using a placebo. When the participants were told that they were receiving anabolic steroids, significant improvements in bench press, squat, and deadlift strength were found. ...
    ... Placebo and OLP treatments have shown promise in enhancing muscular performance in athletes (Ariel and Saville 1972;Maganaris et al. 2000;McClung and Collins 2007;Beedie and Foad 2009) and improving patient outcomes in clinical settings (Sandler and Bodfish 2008;Kaptchuk et al. 2010;Kelley et al. 2012;Carvalho et al. 2016;Hoenemeyer et al. 2018), respectively. We tested the hypothesis that, in untrained adults, placebo and OLP treatments would enhance muscle strength and minimize neuromuscular fatigue. ...
    ... The obvious difference between these types of studies is that patient populations with chronic conditions likely enter into a study hopeful that a given intervention will be helpful in relieving specific symptoms, whereas our participants were college-aged and unaccustomed to rigorous exercise but healthy, nonetheless. In addition to patients, our study's participant population differed from many other placebo interventions that have studied athletes (Maganaris et al. 2000;McClung and Collins 2007;Beedie and Foad 2009). It is not inconceivable to suspect that personality characteristics and motivation levels differ among well-trained athletes and the participants in the present study. ...
  • ... For example, placebo effects in sport performance are a well -documented fact. Athletes who ingested placebos in the guise of caffeine (Beedie, Stuart, Coleman, & Foad, 2006;Duncan, Lyons, & Hankey, 2009), anabolic steroids (Maganaris, Collins, & Sharp, 2000), carbohydrate (Clark, Hopkins, Hawley, & Burke, 2000), or amino acids (Kalasountas, Reed, & Fitzpatrick, 2007) performed their sport tasks better than controls. Placebos can also affect pain experience and induce an anaesthetic effect. ...
    Article
    Full-text available
    Research suggests that placebo can reduce the misinformation effect. We aimed to examine for the first time whether placebo administered in the guise of caffeine can reduce the misinformation effect. One hundred and twenty- -three healthy volunteers were randomly assigned to four groups in a 2 Placebo (Present, Not Present) × 2 Narrative (Misleading, Correct) study design. Participants from placebo groups drank 100 ml of placebo solution. They were told that it was water mixed with caffeine which could positively influence their memory. After three minutes, they watched a short movie clip as an original event and read a narrative with misleading details or correct details as a postevent information; they then completed a 22-item, two-alternative forced-choice questionnaire. The results reveal that the misinformation effect occurred. Although participants in the placebo with misinformation group scored better than participants who did not drink placebo and read the narrative containing misleading details, the difference was not statistically significant. Thus, it is concluded that placebo might not be enough to reduce the misinformation effect when it is administered in the guise of caffeine.
  • ... UDP: umbral de dolor a la presión; ST: Sumación Temporal; ECD: escala de catastrofismo ante el dolor; FPQ: cuestionario del miedo al dolor; STAI: cuestionario del estado de ansiedad en la fuerza máxima que los sujetos eran capaces de producir, mientras que este aumento no se produjo en los sujetos que no tomaron la sustancia placebo. Por otro lado, Maganaris et al., (2000) observaron, en atletas profesionales, que tras la inducción de expectativas positivas con respecto a la ingesta de una sustancia anabolizante placebo consiguieron provocar un aumento de la fuerza máxima en el entrenamiento de levantamiento de peso. Además, se reportó que este aumento se redujo tras eliminar la expectativa positiva además de informar a los sujetos de la composición real de la sustancia placebo. ...
    Article
    Full-text available
    Objetivo: Evaluar cómo las expectativas, inducidas de forma escrita, influyen en la fuerza de prensión manual, en la intensidad de dolor y en variables somato-sensoriales. Diseño: Ensayo piloto controlado y aleatorizado a simple ciego Marco: Campus Universitario. Participantes: Los criterios de inclusión fueron: sujetos sanos, sin dolor y en edades comprendidas entre 18 y 30 años. Una muestra total de 39 sujetos sanos participaron en el presente estudio piloto y fueron asignados aleatoriamente en tres grupos según la expectativa, la cual podía ser positiva, negativa o neutra, dada por escrito Intervenciones: Tras asignar la muestra de manera aleatoria a los tres grupos de expectativas, se les aplicó una corriente de neuro-estimulación eléctrica transcutánea (TENS) de corta duración y sin efecto terapéutico. Variables: La variable principal fue la fuerza de prensión manual. Las variables secundarias fueron la intensidad de dolor, los umbrales de dolor a la presión y la sumación temporal en zona epicondilar. En primer lugar, se recogieron los valores pre-intervención y tras la intervención, se recogieron los datos de las variables de interés en dos tiempos. Primero, inmediatamente después de la intervención y segundo, a los 5 minutos de la misma. Resultados: No se encontraron diferencias estadísticamente significativas en relación a la influencia de las expectativas con el cambio de la fuerza de prensión manual (p > 0,05). No se encontraron diferencias estadísticamente significativas en la sumación temporal, ni en los umbrales de dolor a la presión. El dolor post-intervención fue mayor en el grupo de expectativas negativas y este fue el único grupo que mantuvo el dolor a los 5 minutos tras finalizar la intervención. Conclusión: A pesar de las tendencias observadas, no se encontraron influencias estadísticamente significativas de las expectativas sobre la fuerza muscular de prensión manual, ni en la intensidad de dolor, ni en variables somato-sensoriales. Las expectativas negativas influyeron en el dolor post-intervención.
  • ... Sport-confidence is commonly understood as one of the most critical characteristics influencing the quality of performance in sport (Mahoney, & Avener, 1977;Maganaris, Collins, & Sharp, 2000;Vealey, 2005;Koehn, Pearce, & Morris, 2013). Vealey's (1986) conceptualization of sport-confidence divides it into trait confidence (SC-trait), state confidence (SC-state), and competitive orientation. ...
    Article
    The aim of the study was to validate and adapt the Sources of Sport-Confidence Questionnaire (SSCQ-PL) for use in Poland. The original tool (SSCQ) was created by Robin Vealey (1998) and consists of 41 items grouped into 9 subscales that each describes individual sources of sport-confidence. This paper describes the phases of the adaptation process. A total of 353 Polish athletes participated in the study, including active spor-tsmen, amateurs and professionals. The results confirm satisfactory psychometric properties of the Polish adaptation. The reliability and discriminatory power of the items was high. However, the authors decided to exclude the Situational Favorableness scale, which significantly decreased the reliability of the Polish version of the questionnaire. The internal validity of SSCQ-PL was confirmed using a confirmatory factor analysis. The SSCQ-PL scales correlated with most of the Multidimensional Self-Esteem Inventory (MSEI) scales and with the Trait Sport-Confidence Inventory-PL (TSCI-PL) scales, which confirmed the criterion validity of the tool.
  • ... EEG activity in the alpha frequency band (8)(9)(10)(11)(12)(13) is inversely related to activation of the underlying cortex 24,25 and builds the basis of the valence motivation model 26 . This model associates dominant left relative to right frontal activation, also known as frontal alpha asymmetry (FAA), with an approach motivational system and positive affect 27 . ...
    Article
    Full-text available
    The performance enhancing (ergogenic) placebo effect is elicited by an inert treatment and caused by positive affective appraisal of effort perception. Frontal alpha asymmetry (FAA) is a neurobiological correlate of positive affect. This study investigates, whether receiving an ergogenic placebo increases FAA and whether scores on the behavioral inhibition and activation system (BIS/BAS) scales affect this increase in FAA. Nineteen competitive male cyclists (37.26 ± 9.82 years) performed two maximum effort time trials. The first served as baseline for the second intervention time trial, where athletes received a placebo ergogenic aid or no treatment. We recorded FAA using EEG throughout all time trials and assessed BIS/BAS by questionnaire. There was a significant difference in change from baseline to intervention time trial in FAA during cycling in response to the placebo ergogenic aid compared to the control group. BIS, the BAS subscale Drive and the BAS-BIS difference score significantly co-varied with the change in FAA from baseline to intervention time trial in response to the placebo ergogenic aid. Administering a placebo ergogenic aid significantly influenced FAA during maximum effort cycling. Those athletes with a more pronounced goal seeking persistence and an overall dominance of the BAS over the BIS showed a significantly greater increase in FAA in response to a placebo ergogenic aid. A more pronounced BIS, however, seems to antagonize the increase in FAA associated with the ergogenic placebo response.
  • ... In two other studies [13,14], weightlifters consumed placebo pills they believed to be anabolic steroids and received positive information stating that the pills would improve motor performance. Later, the researchers revealed to the subjects that they merely received a placebo and not real steroids. ...
    Article
    Full-text available
    Background The aim of the study was to examine the influence of the placebo effect on the endurance capacity results in normal weight children. Methods Twenty-four pre-pubertal normal-weight children aged 6–13 years participated in the study. Subjects underwent anthropometric measurements (weight, height, BMI percentile, and fat percentage), a progressive treadmill exercise test to evaluate endurance capacity, and filled habitual activity questionnaire. The participants were examined twice, in a random order, with each child being compared to him/herself. Different types of information were provided regarding a water drink consumed prior to testing- standard information (water) vs. deliberate positive information (presumed energy drink, placebo). Results Following the placebo drink, children demonstrated significantly higher peak pulse (177.9 ± 13.6 vs. 189.8 ± 12.2 bpm), higher stage achieved and longer time of exercise to exhaustion (700.1 ± 155.2 vs. 893.3 ± 150.1 s). Although the exercise duration was longer, stage and heart rate achieved were higher, the reported average, and peak rate of perceived exertion (RPE) were significantly lower for the placebo (18.3 ± 1.4 vs 16.2 ± 1.5). Although the effort was higher while drinking placebo (longer run, higher exercise phase, higher heart rate), recovery time was significantly shorter. The reported differences were not associated with order of tests, age, gender or child activity level. Conclusion Our results demonstrate a significant information placebo effect on children’s endurance capacity test results. This highlights the possible role of positive information (placebo) in trying to encourage physical activity in children. Whether this effect could be applied to longer-term interventions has yet to be tested. Trial registration ClinicalTrial.gov identifier: NCT03165604, Registered May 24, 2017.
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    Neue komplexe motorische Fertigkeiten zu erlernen ist wohl das höchste Erreichbare der bewussten motorischen Steuerung. Diese motorische Lernfähigkeit fußt auf der adaptiven Fähigkeit neuronaler Netze, sich zu reorganisieren.
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    The aim of this review was to determine the magnitude of the placebo and nocebo effect on sport performance. Articles published before March 2019 were located using Medline, Web of Science, PubMed, EBSCO, Science Direct, and Scopus. Studies that examined placebo and nocebo effects of an objective dependent variable on sports performance, which included a control or baseline condition, were included in the analysis. Studies were classified into two categories of ergogenic aids: 1) nutritional and 2) mechanical. Cohen’s d effect sizes were calculated from 32 studies involving 1,513 participants. Small to moderate placebo effects were found for both placebo (d = 0.36) and nocebo (d = 0.37) effects and when separated by nutritional (d = 0.35) and mechanical (d = 0.47) ergogenic aids. The pooled effect size revealed a small to moderate effect size across all studies (d = 0.38). Results suggest that placebo and nocebo effects can exert a small to moderate effect on sports performance.
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    Tested the hypothesis that Ss' expectancies about drug effects on psychomotor performance would predict their responses to drug and placebo. 40 male undergraduates were assigned to 1 of 5 treatments: alcohol (0.56 g/kg), placebo alcohol, caffeine (2.93 mg/kg), placebo caffeine, or no treatment. Groups received preliminary training on a pursuit rotor task before rating the effect that caffeine or alcohol was expected to have on their performance. Ss' performance was measured under the treatments and showed impairment under alcohol and improvement under caffeine. However, regardless of whether they received a drug or placebo, those who expected the most impairment performed the most poorly. Results indicate the importance of expectancies in understanding individual differences in response to drugs and placebos. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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