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

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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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... These expectations can arise from various sources including prior experience, information provided by healthcare providers or another authority such as a coach or having conversations with peers (Bensing and Verheul 2010), or cultural beliefs. When a person has a positive expectation of improvement, their motivational and psychological state can influence perceptions of pain and discomfort, adaptation, selfefficacy, or overall well-being that may chronically influence training and recovery behaviors or acutely influence performance (Maganaris, Collins, and Sharp 2000). ...
... Of the 300+ substances on the PL, the anabolic agents (primarily testosterone) category has the most and best empirical evidence (Heuberger and Cohen 2019) and is probably the most widely recognized among athletes and non-athletes. Maganaris et al. (2000) offered a group of national-level powerlifters the opportunity to participate in a study examining the 'efficacy of a new, fastacting oral anabolic steroid'. The subjects had originally approached the author of the study (who was also their long-time coach) for advice about using steroids to improve their performance. ...
... However, the important distinction is this: there are no policies or sanctions against placebo effects in athletes. Just as Maganaris et al. (2000) did, we could deceive athletes into believing they are taking a banned performance-enhancing substance and those athletes may well experience improved performance, but there are no formal sanctions for that behavior. We could be wrong, and the placebo effects observed in highly trained athletes may not extend into the elite population, but no one would experience career-ending, life-destroying sanctions. ...
Article
Anti-doping policy regulates and punishes the use of substances that are listed on a Prohibited List (PL). These substances are colloquially known as ‘performance-enhancing substances’. There is very little empirical evidence of enhancement for most of the substances on the PL raising the possibility that the perceived enhancement of performance experienced by an athlete is a placebo effect. A placebo effect is a response to an inert substance that is strongly influenced by psychological and social cues in the surrounding environment. It is our contention that, given the lack of proper empirical testing of the substances on the PL, it is in fact the appearance of a substance on the PL that has the strongest performance-enhancing effect in elite athletes. This disconnect between science and WADA’s code raises the question of what we really object to: real performance-enhancement achieved using substances on the PL or performance-enhancement that occurs because WADA has told us that the substance will enhance performance by placing it on the PL? In this case, anti-doping policy would punish those who believe the performance-enhancing myth at the heart of the PL thus leading to a deeply flawed policy that creates its own victims.
... For example, Cussons et al. (2002) provided evidence that the beneficent physical (e.g., strength) and cognitive (e.g., clarity) results of self-injection of markedly subtherapeutic testicular extracts reported by the reputed originator of androgen therapy-Charles E. Brown-Séquard-were almost certainly placebo effects. Reminiscent of this was a small study by Maganaris et al. (2000), wherein an "anabolic steroid" placebo increased maximum performance among elite United Kingdom powerlifters compared to baseline, followed by the loss of observed gains among those men who were informed that they had, in fact, received a placebo. Strikingly, Björkqvist et al.'s (1994) small double-blind study showed that cisgender Finnish men who received placebo testosterone orally reported being angrier and more frustrated, irritable, and This document is copyrighted by the American Psychological Association or one of its allied publishers. ...
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Gender is one of the most essentialized social categories, with putative differences between cisgender men and cisgender women often framed in biological terms. We propose that the consequences of inaccurate and widely held essentialist beliefs about gonadal hormones (EBAGHs) in particular—that is, that androgens signify “men” and estrogens signify “not-men”—have yet to be fully appreciated. For example, placebo effects such as increased strength, sexual desire, and irritability have been documented for the androgen testosterone. Accumulating research also suggests that lay understandings exaggerate the causal importance of testosterone in men’s aggression. Consequently, testosterone is often either eschewed (i.e., men are “poisoned” by it) or enshrined (“more is good, less is bad”). Moreover, the efficacy-bolstering role of estrogens such as estradiol across the physical, cognitive, and sexual health domains for men has been downplayed or ignored by those who assert pejorative links between estrogen and weakness or effeminacy. Critically, EBAGHs may fuel “hypermasculine” behaviors such as excessive red meat consumption, problematic alcohol intake, and anabolic steroid misuse as well as treatment seeking for “low T” in the absence of proper medical diagnosis—which can all, ironically, result in disrupting men’s optimal hormonal balance. Implications of our analysis for research (e.g., EBAGHs as predictors men’s health behaviors, use of bogus “hormonal profiles” to induce or assuage threats to masculinity in experimental studies) and interventions (e.g., “hormone education” to offset the adverse effects of EBAGHs) are discussed.
... We further speculate that informing participants of the placebo disclosure group that any improvement they noticed was to be traced back to their inherent potential, which was brought to light by the placebo, would cushion the disappointment of expectations due to disclosure while safeguarding their self-efficacy in performing the task. Indeed, being confronted with deception and facing the reality of having received a fake treatment could lead to disillusionment and endanger expectations, thus undermining outcome, especially if no positive suggestions on the efficacy of placebos are deployed (as in classic non-deceptive placebo paradigms) (Kalasountas et al., 2007;Maganaris et al., 2000;Sullivan et al., 2005). Nonetheless, in line with findings that post-disclosure detrimental effects may be circumvented through positive rationales on the placebo (Wei et al., 2018), or even with multiple sessions of conditioning (Schafer et al., 2015), our strategy proved successful in preventing detrimental effects on force in the placebo disclosure group. ...
Article
The present study explores whether a particular style of placebo disclosure could serve as a tool to foster a renewed trust in one's own inherent resources and elicit a meaningful placebo effect. In a motor performance task, two placebo groups received inert transcutaneous electrical nerve stimulation (TENS) in each of four sessions along with information on its force‐enhancing properties. Before the final session, one of the placebo groups was informed about the placebo, which was portrayed as a means to unleash an inherent potential. Along with force, we systematically monitored task‐specific self‐efficacy to test whether this variable would be differentially modulated in the two placebo groups. Compared to two control groups, placebo groups showed higher force and self‐efficacy in the last session. No differences in self‐efficacy were observed in the placebo groups even after revealing the placebo procedure, suggesting that the disclosure was effective in ‘safeguarding’ individuals' self‐efficacy. These findings may have important implications, paving the way for the use of placebos that not only are ethically permissible but also support individuals' self‐efficacy.
... The placebo effect is present and significant also in the treatment of sport-active patients [25,53]. For example, it has been demonstrated that athletes who falsely believed they had been administered anabolic steroids performed better than their baseline or when compared with controls [33]. Similarly, another study reported significant improvements in 3000-m running time when participants self-injected intra-muscle saline, which they believed was a substance similar to recombinant erythropoietin [48]. ...
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Purpose The aim of this systematic review was to analyse the available clinical evidence on intra-articular knee injections for the treatment of degenerative cartilage lesions and osteoarthritis (OA) in sport-active patients. Methods A literature search was performed in July 2023 according to the PRISMA guidelines on three electronic databases (PubMed, Cochrane, Web of Science). Studies addressing intra-articular injections for degenerative knee cartilage lesions or knee OA in sport-active patients were included. The Downs and Black’s “checklist for measuring quality” was used to evaluate risk of bias and quality of the included studies. Results Only 10 clinical studies for a total of 296 sport-active patients were included, with a publication trend increasing over time. The studies were 9 case series and 1 RCT; 7 studies focused on hyaluronic acid (HA), 2 studies focused on platelet-rich plasma (PRP), while 1 study compared HA and PRP. Overall, safety and positive clinical findings were for both HA and PRP, although not always with satisfactory results in terms of return to sport. The Downs and Black evaluation showed an overall poor quality of the included studies, with an average score of 21.1 points (range 19–25). Conclusions The available clinical evidence is still limited, with only a few studies published and an overall low-quality of evidence, suggesting a potential role of HA and PRP injections to treat these patients. However, further high-level trials are needed to confirm the real benefits of these treatments for the management of sport-active patients affected by degenerative cartilage lesions or OA of the knee.
... While not tested within this project, it is possible that improvements to soccer-specific performance could be a consequence of the player's perceived improvement in traction since the player cannot be blinded to the condition. Several studies have suggested that changes in proprioceptive feedback (Hasan et al., 2016) or placebo effect (Clark et al., 2000;Maganaris et al., 2000) are contributing factors to improved performance of GS. It should be noted that peak forces in the lateral forefoot were different between sock conditions when ball striking from 22.0 m and 27.5 m in the present study. ...
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Textured grip socks are worn by soccer players worldwide to decrease foot movement within the shoe and improve athletic performance. The purpose of this study was to investigate the effects of textured grip socks on performance and in-shoe plantar kinetics during soccer-specific tasks. Eleven collegiate soccer players (4 male, 7 female) participated in this study. Performance and in-shoe kinetic data were collected under 2 sock conditions (normal soccer socks and grip socks) during 3 change-of-direction drills (45-degree, 90-degree, 180-degree changes-of-direction) and 3 soccer-specific drills (dribbling, ball striking, juggling). Kinetic data were recorded across 3 plantar regions (hindfoot, medial forefoot, lateral forefoot) via insoles worn in the shoe and utilized to calculate impulse and peak force. Performance was assessed via time-to-completion (change-of-direction and dribbling drills) or number of successful repetitions (juggling and ball striking drills). Compared to normal soccer socks, grip socks improved performance during dribbling (P = 0.02), dominant limb juggling (P = 0.03), and ball striking at 3 distances (P = 0.04, <0.01, <0.001). Grip socks decreased 180-degree change-of-direction performance (P = 0.03). Hindfoot impulse was smaller during the 45- (P = 0.02) and 90-degree (P = 0.02) change-of-direction drills in grip socks. Hindfoot peak force was smaller during the 90-degree change-of-direction (P = 0.05); medial forefoot (P = 0.02) and total foot (P = 0.02) peak force were greater during the 45-degree change-of-direction drill in grip socks. Despite improvements in soccer-specific performance with grip socks, the lack of consistent significant differences among plantar kinetics indicate that performance outcomes may be driven by at least one other mechanism (e.g., placebo, somatosensory feedback).
... Maganaris et al reported performance enhancement among weightlifters who were led to believe that they had received anabolic steroids (placebo). The athletes' performance returned to baseline levels after they had been informed of the true nature of the drug [21]. In the present study, we did not observe any significant changes in flexor muscle strength in the group with positive verbal suggestions. ...
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Background Words uttered by other people can have an enormous influence on how we perceive our surroundings, what we expect, what we experience, and how we behave. This study aimed to evaluate the effect of verbal reinforcement on the placebo effect in the context of finger flexor muscle activation measured with surface electromyography (sEMG) and hand grip strength measured with a hand dynamometer in healthy subjects. Material/Methods Eighty-eight individuals aged 22.64±5.2 years took part in the study. For each person, paper tape was applied (placebo). The participants were randomly assigned to 1 of the 3 groups: positive information group (P) – “the tape increases hand muscle strength”, negative information group (N) – “the tape decreases hand muscle strength”, and control group (C) – “the effect of the tape on hand muscle strength is unknown.” The activation of muscles was assessed using surface electromyography (sEMG) while measuring the strength of wrist and finger flexors with a hand dynamometer. Each participant was examined twice – prior to and immediately after taping and providing verbal reinforcement. Results Only group N manifested a decrease in muscle strength, from 39.7N to 37.6N (P=0.003). Group C displayed an increase in muscle strength from 34.3N to 36.4N (P=0.035). None of the groups demonstrated statistically significant changes in bioelectrical activity of the muscles. At no stage of examination were the differences between the groups significant. Conclusions Negative verbal information combined with the placebo intervention resulted in a significant decrease in the strength of finger flexors.
... Contrary to previous work, in the present study, we used the novel Blinded-Dose Purchase Task to assess reinforcing value of the dose effects of cocaine and methamphetamine and a single dose of alcohol, while controlling for drug expectancies in populations that had familiarity with the drug or drug class and varying levels of use (e.g., recreational alcohol use, cocaine dependence). Hypothetical drug purchase tasks have rarely accounted for drug expectancies, which are thought to impact a wide range of outcomes across numerous drug classes (Berna et al., 2017;Chermack & Taylor, 1995;Jaffe & Kilbey, 1994;Leventhal & Schmitz, 2006;Maganaris et al., 2000;Schafer & Brown, 1991;Testa, 2002;Volkow et al., 2003). For example, Aston et al. (2021) used qualitative methods to inform the design of a hypothetical cannabis purchase task. ...
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Rationale: Behavioral economic drug purchase tasks quantify the reinforcing value of a drug (i.e., demand). Although widely used to assess demand, drug expectancies are rarely accounted for and may introduce variability across participants given diverse drug experiences. Objectives: Three experiments validated and extended previous hypothetical purchase tasks by using blinded drug dose as a reinforcing stimulus, and determined hypothetical demand for experienced effects while controlling for drug expectancies. Methods: Across three double-blind, placebo-controlled, within-subject experiments, cocaine (0, 125, 250 mg/70 kg; n=12), methamphetamine (0, 20, 40 mg; n=19), and alcohol (0, 1 g/kg alcohol; n=25) were administered and demand was assessed using the Blinded-Dose Purchase Task. Participants answered questions regarding simulated purchasing of the blinded drug dose across increasing prices. Demand metrics, subjective effects, and self-reported real-world monetary spending on drugs were evaluated. Results: Data were well modeled by the demand curve function, with significantly higher intensity (purchasing at low prices) for active drug doses compared to placebo for all experiments. Unit-price analyses revealed more persistent consumption across prices (lower α) in the higher compared to lower active dose condition for methamphetamine (a similar non-significant finding emerged for cocaine). Significant associations between demand metrics, peak subjective effects, and real-world spending on drugs also emerged across all experiments. Conclusions: Orderly demand curve data revealed differences across drug and placebo conditions, and relations to real-world measures of drug spending, and subjective effects. Unit-price analyses enabled parsimonious comparisons across doses. Results lend credence to the validity of the Blinded-Dose Purchase Task, which allows for control of drug expectancies.
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Placebo and nocebo effects have been well documented for nearly two centuries. However, research has only relatively recently begun to explicate the neurobiological underpinnings of these phenomena. Similarly, research on the broader social implications of placebo/nocebo effects, especially within healthcare delivery settings, is in a nascent stage. Biological and psychosocial outcomes of placebo/nocebo effects are of equal relevance. A common pathway for such outcomes is the endogenous opioid system. This chapter describes the history of placebo/nocebo in medicine; delineates the current state of the literature related to placebo/nocebo in relation to pain modulation; summarizes research findings related to human performance in sports and exercise; discusses the implications of placebo/nocebo effects among diverse patient populations; and describes placebo/nocebo influences in research related to psychopharmacology, including the relevance of endogenous opioids to new lines of research on antidepressant pharmacotherapies.
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Purpose: Research in recent decades has shed light on the neurophysiological mechanisms of pain, which not only hasan information and warning function, but is also considered an important diagnostic factor. The results of various studiesindicate that physical activity, especially at moderate intensity, modulates the intensity of perceived pain and generally leadsto its reduction.The aim of this study was to characterize in depth the effects of physical activity on pain perception, inparticular to deepen the knowledge of the direct and indirect effects of recurrent repetitive injuries on pain perception andmodulation of the activity of the endogenous antinociceptive system.Methods: This article reviews the current state of knowledge on the effects of physical activity and injury on pain perceptionand the role of the endogenous analgesic system in pain modulation.Results: Both excessive physical effort and a lack of physical activity are factors that increase the risk of pain. Physicalactivity, especially training in athletes, exerts loads on the locomotor system structures and by means of the nociceptivesystem signalises potential hazards through pain. At the same time, these very same loads trigger the processes activating theendogenous analgesia systems. In the case of intense and prolonged physical activity, these systems are subject to adaptationas well as exhaustion.Conclusions: For athletes and amateur athletes, knowledge about pain has a practical dimension, enabling conscious,knowledge-based monitoring of applied loads and control of the body's condition. Gaining knowledge about pain in sportscan be of great practical importance in the in the training process, during the competition but above all the prevention ofinjuries. The intensity and quality of pain, although these are subjective feelings, can be defined and analyzed in clinicalpractice and in research conducted on physically active people, using established procedures and appropriate tests.
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This book sheds light on the translation of current mechanistic research on placebo effects to develop comprehensive and adequate strategies for better symptom management and treatment. This book identifies three core aspects to bridge state-of-the-art concepts with day-to-day clinical practice. First, lessons from mechanistic placebo research indicate a neurobiological basis underlying placebo effects. Second, placebo research can improve the design of clinical trials to advance drug development. Third, placebo effects can be exploited in daily clinical practice to optimize patient-clinician communication and relationships and clinical outcomes. Together, these three core aspects provide a new perspective with which to appraise the implications of Placebo Research for healthcare systems, clinicians, patients, and caregivers. New patient-centered approaches, mental health, and pain-related issues are discussed while describing technologically advanced and novel research applications that will shift current clinical practice to improve treatment outcomes.
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