Placebo and Nocebo Effects on Sports and Exercise Performance: A Systematic Literature Review Update.

Sports performance could be affected by placebo and nocebo effects. The last literature review on placebo and nocebo effects on sports and exercise performance was published in 2019. In the past five years, several new studies have been published. This review aimed to update the previous synthesis and evaluate the results of new studies focusing on placebo or nocebo interventions in sports and exercise by determining the form and magnitude of their effect. Hence, we searched for empirical studies published from 2019 until the end of May 2024 indexed in PubMed, Medline, Web of Science, EBSCO, and Google Scholar databases. The search yielded 20 eligible studies with control or baseline-control conditions, focusing on nutritional, mechanical, and other mixed ergogenic aids. They yielded small to large placebo effects (Cohen's d) for nutritional (d = 0.86), mechanical (d = 0.38), cream and gel (d = 0.05), and open-label placebo (d = 0.16) interventions. The pooled effect size for placebo effects was moderate to large (d = 0.67), larger than in the earlier review, suggesting that placebo effects can improve motor performance even more than previously reported. However, based on five measures from three studies, the nocebo effects were almost twice as large (d = 1.20). Accordingly, the current findings support and expand the last review in the field by yielding additional support for placebo and nocebo effects in sports and exercise.

Do the effects last? A comparison between internal and external focus of attention instructions on golf putting accuracy over multiple days.

Background: The role of attentional focus is a well-explored topic in exercise sciences. Studies generally indicate that external focus (EF) enhances motor performance and learning compared with internal focus (IF). However, most studies only included one or two experimental days which limits participants' exposure to the focus conditions. This raises the question of whether the superiority of EF varies over time. Methods: Accordingly, in this pre-registered within-subject study, we examined the effects of focus instructions on golf-putting performance over four days, with 48-72 h between them. On each day, participants performed 15 putts under three instructional conditions: (1) EF, (2) IF, and (3) control, in a randomized and counterbalanced order. Results: We observed trivial differences in performance between conditions but considerable improvements from day 1 to day 4. When using an exploratory analysis, we found that participants performed better under EF and control conditions compared with the IF condition on day 1, but not on subsequent days. Conclusions: Since IF instructions are more commonly used in practice, we speculate that the two other focus conditions were experienced as more novel, potentially accounting for their superiority on Day 1. Nevertheless, our results question the significance of employing EF to enhance performance.

Effect of intensity training block on anxiety state and performance in competitive swimmers.

Background: An increase in training intensity could create changes in psychological and physiological variables in competitive athletes. For this reason, it is very relevant to know how an intensive training block could influence psychological variables in competitive swimmers. This study examined the effect of an intensive training block (HIT) for 2 weeks on the anxiety state and swimming performance compared to standard aerobic training. Methods: Twenty-two male competition swimmers were randomly assigned to two groups: HIT group (n = 11; age = 16.5 ± 0.29 years) and control group following the standard training program (n = 11; age = 16.1 ± 0.33 years). Psychological status variables (cognitive anxiety, somatic anxiety and self-confidence) and swimming performance (100-m front crawl) were measured pre-and post-test. Results: A significant effect of time was found for all psychological variables and swimming performance (F ≥ 17.6; p < 0.001; d ≥ 0.97). Furthermore, a significant group × time interaction effect was found in cognitive (F = 14.9; p < 0.001; d = 0.62) and somatic anxiety (F = 5.37; p = 0.031; d = 0.55) were found. Only a significant group effect was found in somatic anxiety (F = 27.1; p < 0.001; d = 1.2). Post hoc comparison revealed that both groups increased their cognitive anxiety and swimming performance, and decreased their self-confidence from pre to post test. However, cognitive anxiety increase significantly more in the HIT group compared to the control group. Furthermore, only the HIT training group significantly increased somatic anxiety over time, while somatic anxiety did not change significantly over time in the control group. Conclusion: Our findings indicated that a sudden increase in training intensity increased state anxiety more than standard training, but both conditions similarly enhanced swimming performance. Although the current level of psychological state is not affecting swimming performance negatively over this period, it should be regularly monitored by psychologists as it over a longer training period perhaps could have a negative influence on swimming performance.

Exploring characteristics of and transitions between mental states within the Multi-Action Plan model in high-level judo.

The Multi-Action Plan (MAP) model presents an idiosyncratic framework for human performance. MAP research has categorised four Performance Types (PTs; T1-T4) using self-paced activities. Specifically, T1-4 present four distinct mental states experienced by athletes during performance, differing, among other aspects, in the level of effort and perceived control. However, transitions between PTs are yet to be empirically investigated. This study aimed to examine MAP in the hyperdynamic open-skill combat context of judo. We explored how judoka experienced PTs and the transition processes between these mental states. Six British, high-level judoka (n = 6; Mdnage = 19) were interviewed using a retrospective semi-structured interview schedule. Interpretative phenomenological analysis indicated that judo presents a hyperdynamic difficult-to-predict performance context due to the opponent and fighting rhythm. Second, participants strongly related to T2 and T3 and less to T1 and T4. They also reported experiences 'between' T2 and T3. Lastly, participants reported common transition pathways (e.g., T2-T3), typical transition cues, and specific trainable strategies to optimise performance. Findings are discussed in relation to existing literature. Lastly, we present limitations, applied, and research considerations.

The effect of internal, external, and holistic focus of attention on standing long jump performance in novice and skilled karatekas.

An important application for training instructions is found in directing one's attentional focus. This direction can occur in different internal, external, or holistic forms. However, comparison between these three forms of instructions is a relatively recent development rarely reported at different skill levels or various sports including karate. Therefore, the present study attempts to investigate the effects of three forms of instructions on standing long jump performance in skilled and novice karatekas. The participants were 60 skilled and novice karatekas (all females; mean age: 21.32 ± 1.65) who completed 12 standing long jump trials under different focus conditions (3 trials for each condition: internal, external, holistic and control condition) in a counterbalanced order. Our findings suggested significant main effects, indicating that skilled karatekas outperformed the novices. The findings also showed that regardless of skill levels, the participants exhibited similar performance under external and holistic focus conditions while performance in both of these conditions was superior compared to performance under internal focus and control conditions. No difference was observed between the control and internal focus conditions. It seems that skilled and novice karatekas may benefit from holistic and external focus of attention instructions which enhance their motor performance. Thus, it is recommended that coaches should incorporate these two types of attentional focus instructions into their training sessions.

The effect of experience on the perception of affordances for aperture crossing in cycling.

To ride successfully and safely, cyclists must perceive and act on the affordances that are available in a given situation. This study investigated whether experience in perceiving and acting with respect to a person-plus-object system would influence whether and how a person choses to cross an aperture of different widths, especially in relation to their maximal action capabilities. We also explore whether the distribution of action modes reflects this effect. We examined the performance (i.e., the probability of successfully crossing the aperture) and the decision (i.e., the probability of attempting to cross the aperture) of 8 experienced cyclists and 16 occasional cyclists in an aperture crossing task. In term of performance, experienced cyclists demonstrated greater ability to cross narrower apertures than occasional cyclists, but there were no such differences when aperture width was scaled to maximal action capabilities. In term of decision, both experienced and occasional cyclists tended to over-estimate their abilities, but the experienced cyclists did so to a greater extent. Our findings indicate that experience improves the ability to perform more complex tasks due to utilizing a wider repertoire of actions, but not necessarily the ability to perceive and actualize (action-scaled) affordances.

Investigating in-performance transitions between mental states in high-level judoka using video-based stimulated recall.

The Multi-Action Plan model offers an idiosyncratic, sport-specific, and applied framework categorising two peak (Type 1 & 2) and two non-peak performance types (Type 3 & 4). The purpose of the present study was to examine the transitions between these Performance Types across three competition-simulating training judo fights. After videoing three judo fights per participant, we interviewed six high-level judo practitioners (Mdage = 19 years) using video-stimulated recall. While watching their fights, participants indicated which Performance Types they experienced during each fight and, subsequently, discussed their experience with the lead researcher. Findings indicated that participants spent most time in effortful mental states (Type 2 & 3). Additionally, they identified currently not defined states 'between' current typologies, e.g., T2.5. Overall, participants reported more down- than upregulations. Specifically, they described downregulations as mostly uncontrolled and related to fatigue, technical-tactical, or cognitive-emotional transition cues. In contrast, they characterised upregulations as deliberate and proactive mental resets, utilising strategies such as self-talk. Lastly, we discussed our findings in relation to existing literature and offered implications for research and practice.

Effects of 6-Week Motor-Cognitive Agility Training on Football Test Performance in Adult Amateur Players - A Three-Armed Randomized Controlled Trial.

Agility, defined as the ability to rapidly respond to unforeseen events, constitutes a central performance component in football. Existing agility training approaches often focus on change of direction that does not reflect the complex motor-cognitive demands on the pitch. The objective of this study is to examine the effects of a novel motor-cognitive dual-task agility training (Multiple-object tracking integrated into agility training) on agility and football-specific test performance parameters, compared to agility and a change of direction (COD) training. Adult male amateur football players (n = 42; age: 27±6; height: 181±7cm; weight: 80±12kg) were randomly allocated to one of the three intervention groups (COD, agility, agility + multiple object tracking). The Loughborough Soccer Passing Test (LSPT), a dribbling test with/without cognitive task as well as the Random Star Run (with/without ball) and the modified T-Test were assessed before and after a 6-week training period. Time effects within the T-Test (F = 83.9; p < 0.001; η2 = 0.68) and dribbling test without cognitive task (F = 23.9; p < 0.001; η2 = 0.38) with improvements of all intervention groups (p < 0.05) were found. Dribbling with cognitive task revealed a time effect (F = 7.8; p = 0.008; η2 = 0.17), with improvements exclusively in the agility and dual-task agility groups (p < 0.05). Random Star Run with and without ball exhibited a time (F = 38.8; p < 0.001; η2 = 0.5; F = 82.7; p < 0.001; η2 = 0.68) and interaction effect (F = 14.14; p < 0.001; η2 = 0.42; F = 27.8; p < 0.001; η2 = 0.59), with improvements for the agility and dual-task agility groups. LSPT showed no time, group or interaction effect. The effects of change of direction training are limited to change of direction and dribbling test performance within preplanned scenarios. In contrast, motor-cognitive agility interventions result in notable enhancements in football-specific and agility tests, incorporating decision-making and multitasking components. No differences were observed between agility and agility + multiple object tracking. To achieve a transfer to game-relevant performance, coaches should focus on integrating cognitive challenges into motor training.

Warm-up music and low-dose caffeine enhance the activity profile and psychophysiological responses during simulated combat in female taekwondo athletes.

To assess the effects of warm-up music and low dose (3 mg·kg-1) of caffeine (CAF) on female taekwondo athlete's activity profile and psychophysiological responses during simulated combat. In a double-blinded, randomized, crossover study, 16 female athletes participated in simulated combats under one control and 5 experimental conditions [i.e., CAF alone (CAF), placebo alone (PL), CAF with music (CAF + M), PL with music (PL + M), and no supplement with music (M)]. After warming-up, athletes rated their felt arousal (FAS). Mean (HRmean) and peak (HRpeak) heart rate values were determined for each combat. After fighting, athletes rated their perceived exertion (RPE), feeling scale (FS), FAS, and physical enjoyment (PACES). Time-motion and technical-tactical variables were analyzed. CAF + M induced shorter skip and pause time, while attack time increased compared to other conditions (p < 0.05). Moreover, CAF + M increased single attacks, combined attacks, counter-attacks (p < 0.001), and defensive actions (p < 0.05) than other conditions. HRmean and HRpeak were lower under CAF + M than other conditions (p < 0.05). Additionally, higher FAS post-combat, FS, and PACES were observed under CAF + M, while RPE was lower (except CAF condition) compared to the other conditions (p < 0.05.Using CAF with warm-up music may increase combat cadence and improve the psychological state in female athletes more effectively than either strategy alone.

Do negative stereotypes and domain identification moderate novice participants' performance on a soccer-dribbling task ?

The present research aimed to explore whether negative stereotypes and domain identification moderate novice participants' performance on a soccer-dribbling task, using a novel statistical procedure to explore within-subjects moderation effects. Fifty-four women with no soccer experience (Mage = 19.92, SDage = 1.0) were recruited and assigned to a negative stereotype condition or a nullified-stereotype condition and performed a soccer-dribbling task as fast as possible. Using moderation analyses for repeated measures, results showed (i) that inducing a negative stereotype did not moderate participants' performance, and (ii) that domain identification did not moderate participants' performance in a stereotype threat situation. In conclusion, the novice participants performance did not depend on the value of domain identification and the stereotype condition. More research is nonetheless needed to disentangle the question of how and why novice participants can be impacted by a stereotype threat situation.

Fatigued or bored? Investigating the effect of different types of mental fatigue on 3 km running performance.

Mental fatigue has been highly cited as having a negative impact on endurance performance. Few, however, have investigated whether different types of mental fatigue, namely active and passive fatigue, might affect endurance performance differently. This study used a repeated-measures design where 11 participants completed a 3 km run after three 32-min conditions: an actively fatiguing task (Task-load Dual-back; TloadDback); a passively fatiguing task (Mackworth Clock); and a control task (Documentary). Subjective ratings and performance on a second task (Flanker task) were taken before and after the 32-min tasks, while ratings of perceived effort, motivation and workload were taken during the 3 km run. Results showed that both fatigue conditions were mentally fatiguing, with the TloadDback rated as more demanding and the Mackworth Clock more boring and less motivating. Performance on subsequent tasks showed different effects: the TloadDback condition had the slowest responses on the post-test Flanker task, while the Mackworth Clock condition had the slowest completion time on the 3 km run, though this difference in completion times was non-significant. These results suggest that different cognitive tasks lead to different types of mental fatigue, which can lead to different outcomes on subsequent cognitive tasks but non-significant differences on subsequent physical tasks. This study highlights that to understand the influence of mental fatigue on physical performance, it is important to understand the cognitive tasks used and how different cognitive and physical tasks interact. Future work should examine whether performance outcomes in other areas commonly affected by mental fatigue, like technical and tactical sporting skills, are affected differently by active and passive fatigue.

Resilience profiles of elite athletes and their associations with health-related behaviors, well-being, and performance: A latent profile analysis.

Resilience is an important factor in the performances of elite athletes as it helps them overcome the adversity they face on a daily basis. It is a dynamic process with resilience qualities evolving throughout athletes' sporting careers. Recent research has established links between resilience, sports performance, lifestyle, and health-related factors. However, no study has yet focused on the resilience profiles of athletes (i.e., sub-groups of individuals with similar levels of different resilience qualities). The aims of this study were to: (a) explore the resilience profiles of elite athletes, (b) determine the characteristics of these resilience profiles (i.e., health-related behaviors, well-being, perceived social support), and (c) determine the correlates of these profiles at intrapersonal and interpersonal levels. Latent profile analysis was performed on 307 French elite athletes. Results revealed "high resilience" and "moderate resilience" profiles. Athletes with "high resilience" profiles were more likely to be men, exhibit better health-related behaviors, and have higher levels of psychological well-being and perceived performance. High levels of conscientiousness, extraversion, the dimensions of the coach-athlete relationship and the motivational climate were also related to the "high resilience" profile. This study is the first to explore the resilience profiles of elite athletes. The results suggest that a high level of resilience is related to the adoption of health-related behaviors favorable to elite sport. Based on these findings, health promotion programs targeting the concept of resilience should be developed in elite sport centers for athletes, coaches, and parents.

Ego depletion does not negatively impact novice sprinters' start performance during a timed 20m all-out sprint.

Temporary reductions in self-control due to previous cognitive effort, also known as 'ego depletion', have been shown to negatively impact performance in subsequent tasks requiring self-control. Various theoretical accounts suggest that high levels of task motivation may prevent negative behavioural effects of ego depletion. Against this background, the current study performed a conceptual replication of a previous study examining the effects of ego depletion on sprint start performance (i.e., Englert et al., 2015) and implemented additional monetary incentives to manipulate task motivation. Using a pretest-intervention-posttest design, ninety-six novice sprinters performed a sprinting task that required them to complete a series of 20-m sprints. In between pretest and posttest, participants performed a letter writing task either under high cognitive demand (depletion group) or low cognitive demand (non-depletion control group). Subsequently, and prior to starting the posttest, participants were presented either with a monetary incentive or no incentive. Manipulation checks confirmed that the letter writing task successfully manipulated perceived regulatory demand and that task motivation at the posttest was higher for participants who were offered a monetary incentive. The number of false starts decreased significantly with ego depletion, while sprint start reaction times and sprint finish times remained unaffected. Regardless of ego depletion, sprint finish times significantly improved with monetary incentives. These results suggest that brief engagement in a demanding cognitive task is unlikely to impair novice sprinters' ability to self-regulate during the start of a subsequent, maximal sprinting effort for which they are highly motivated.

The Cognitive Function and Taekwondo-Specific Kick Performance of Taekwondo Athletes at Different Hydration Statuses.

PURPOSE: Successful participation in taekwondo (TKD) requires athletes to possess quick decision-making abilities and demonstrate technical proficiency during competition. Dehydration, occurring during both training and competition, is widely recognized to have various negative effects. METHODS: This study investigated the impact of different levels of dehydration on cognitive function, as measured by the Vienna Test System, and the specific performance of kicking techniques among TKD athletes. Using a randomized crossover design, 12 participants were involved in the study. Before and after 1 hour of training at 80% of maximal heart rate, participants were weighed and provided urine samples. All participants were randomly assigned to 3 different hydration conditions: the euhydrated (EUH) group had unrestricted access to fluid consumption, while the hypohydrated (HYP) and severely HYP (S-HYP) groups experienced reductions of 2.0% and 4.0% of their initial body weight, respectively. RESULTS: The EUH group exhibited better reaction speed in reaction-time test-form S1 than the HYP and S-HYP groups. Notably, the EUH group demonstrated a significantly higher success rate in the front-side kick (EUH 98%, HYP 90%, S-HYP 88%; P < .05). However, the success rates of back roundhouse kick and free head kick were similar among the 3 statuses. Furthermore, postexercise heart rates were found to be significantly higher in the HYP and S-HYP groups compared with the EUH group. CONCLUSIONS: This study provides insight into the negative effects of dehydration on cognitive function and TKD-specific performance. It is recommended that TKD athletes maintain optimal hydration levels during training and competition to ensure optimal performance.

Coping strategies and brain activity in table tennis players faced with discrepancies between predicted and actual outcomes.

Prior studies have shown that experts possess an excellent ability for action anticipation. However, it is not clear how experts process the discrepancies between predicted outcomes and actual outcomes. Based on Bayesian theory, Experiment 1 in the current study explored this question by categorizing unexpected outcomes into gradually increasing discrepancies and comparing the performance of experts and novices on a congruence discrimination task. Our behavioral analysis revealed that experts outperformed novices significantly in detecting these discrepancies. The following electroencephalogram study in Experiment 2 was conducted focused exclusively on experts to examine the role of theta wave oscillations within the mid-frontal cortex in processing varying levels of discrepancy. The results showed that reaction time and theta oscillations gradually increased as the magnitude of discrepancy increased. These findings indicate that compared to the novices, experts have a better ability to perceptual the discrepancy. Also, the magnitude of discrepancies induced an increase in mid-frontal theta in experts, providing greater flexibility in their response strategies.

Study on the relationship between fixation characteristics and hit rate in psychological procedure training of free throw.

BACKGROUND: Free throw is an important means of scoring in basketball games. With the improvement of basketball competition level and the enhancement of confrontation degree, the number of free throws in the game gradually increases, so the score of free throw will have an important impact on the result of the game. The purpose of this study is to explore the relationship between visual attention characteristics and hit rate of basketball players in free throw psychological procedure training, so as to provide scientific basis for basketball teaching and training. METHODS: Forty players with similar free throw abilities were randomly assigned to the experimental group (10 males, 10 females) and control group (10 males, 10 females). The experimental group was free throw psychological procedure training, while the control group was trained with routine training, Eye movement indices (number of fixations, fixation duration, and pupil dilation) and the free throw hit rate and analyzed before and after the experiment. Group differences were examined using t-tests, while paired sample t-tests were conducted to compare pre- and post-test results within each group. The training time and training times of the two groups were the same. RESULTS: There were significant differences in fixation duration, number of fixations, pupil diameter and free throw hit rate between pre-test and post-test in the experimental group (P < 0.05). Post-test, there were significant differences in number of fixations, fixation duration, pupil diameter and free throw hit rate between the two groups (P < 0.05). There was a significant positive correlation between number of fixations and free throw hit rate in top (P < 0.01), and there was a significant positive correlation between fixation duration and hit rate in front (P < 0.01). CONCLUSIONS: The psychological procedure training can improve the visual information search strategy and information processing ability of free throw, and significantly improve the free throw hit rate. There was a positive correlation between the front fixation time and the free throw hit rate, and there was a positive correlation between the top number of fixations and the free throw hit rate.

The effects of coaches' pride and shame expressions on field hockey players' emotions and performance.

In this study, we examined the effects of female coaches' nonverbal pride and shame expressions on female field hockey players' emotions and performance and considered the role of two potential moderating factors. Across two experiments, a between (emotional expression manipulation) within (pre- and post-manipulation) subjects design was employed. A female hockey coach was scripted to deliver performance feedback randomly displaying pride or shame to skilled players (Experiment 1, n = 38; Experiment 2, n = 44) after they had performed a passing test. Players then performed the passing test for a second time. In both experiments, players reported their emotions, perceptions of the coach, and connection with the coach. In Experiment 2, players also rated their emotion regulation ability. The results showed that displayed pride elicited pride in players while displayed shame elicited shame in players. Further, coaches' pride and shame expressions had differential effects on players' performance. Displayed pride consistently improved players' performance. Displayed shame mainly worsened performance, but players' ability to regulate their own emotions seemed to buffer these negative effects. There was further evidence that players' emotions could underpin the performance effects, particularly when players knew the coach. These findings advance the literature by providing further experimental evidence for when and how coaches' pride and shame expressions influence players' emotions and performance and have important practical implications for coaches aiming to optimize performance.

University serial winning coaches' experiences with low performance and maladaptive team culture.

We sought to explore the strategies and behaviours employed by University serial winning coaches during seasons of both low performance and a maladaptive team culture. We interviewed seven University team sport coaches and subsequently analyzed the data using a reflexive thematic analysis (RTA). Results indicated that our coaches generally felt unprepared for the unexpected and challenging season, leading to increased stress and decreased psychological well-being. Coaches experienced frustration, disappointment, and self-doubt, which was either exacerbated or mitigated by their access to social support. Despite the emotional turmoil coaches experienced, they were able to reflect on their actions and take away key lessons, helping them perform well in the future. Findings provide insight into how winning coaches manage and overcome inevitable adverse situations. Moreover, these results provide a deeper understanding of how these highly successful coaches navigate these key challenges that over time can inform policy and practice in coach development. These coaching strategies may help coaches of all levels overcome barriers to success and may be transferable to leaders of all levels across a range of disciplines outside of sport.

The impact of soccer-specific psychophysiological stress on inhibition and cognitive flexibility in elite youth players.

While researchers and practitioners attribute an essential role to executive functions (EFs) for soccer performance, the usefulness of respective diagnostics and the predictive value remain unclear. One limitation restricting the translation and relevance of study results to improve actual game performance is the insufficient consideration of competitive conditions. Thus, this study aimed to conduct soccer-specific cognitive diagnostics under a soccer-specific psychophysiological stress condition, mimicing the demands of a competitive game. A total of 92 (Mage = 15.17, SDage = 1.45) youth elite players performed tests for inhibition (flanker task) or cognitive flexibility (number-letter task) with a soccer-specific motor response (i.e., pass into goals). After a pre-test in a neutral condition, players were randomly assigned to a neutral (moderate soccer-specific exercise) or a stress condition (physical stress and competitive instructions and filming for psychological stress). Objective (i.e., cortisol, heart rate variability) and subjective stress-related measures (i.e., SAM, VAS) were assessed six times throughout experimental procedure. Analyses revealed significant interaction effects between time and condition for all objective and subjective variables indicating a successful experimental stress induction. For cognitive performance, results revealed significant main effects of time, but no significant interaction effects between time and condition. However, descriptive statistics suggested improved performance under stress, with decreased flanker effect and switch costs. Additionally, response time variability in the flanker task significantly decreased in the stress condition. These findings offer insights into individual stress perception and processing under game-related psychophysiological demands, expanding previous research on situational EF alterations that also hold relevance for applied practitioners.