Synthetic Data as a Strategy to Resolve Data Privacy and Confidentiality Concerns in the Sport Sciences: Practical Examples and an R Shiny Application

PURPOSE

There has been a proliferation in technologies in the sport performance environment that collect increasingly larger quantities of athlete data. These data have the potential to be personal, sensitive, and revealing and raise privacy and confidentiality concerns. A solution may be the use of synthetic data, which mimic the properties of the original data. The aim of this study was to provide examples of synthetic data generation to demonstrate its practical use and to deploy a freely available web-based R Shiny application to generate synthetic data.

METHODS

Openly available data from 2 previously published studies were obtained, representing typical data sets of (1) field- and gym-based team-sport external and internal load during a preseason period (n = 28) and (2) performance and subjective changes from before to after the posttraining intervention (n = 22). Synthetic data were generated using the synthpop package in R Studio software, and comparisons between the original and synthetic data sets were made through Welch t tests and the distributional similarity standardized propensity mean squared error statistic.

RESULTS

There were no significant differences between the original and more synthetic data sets across all variables examined in both data sets (P > .05). Further, there was distributional similarity (ie, low standardized propensity mean squared error) between the original observed and synthetic data sets.

CONCLUSIONS

These findings highlight the potential use of synthetic data as a practical solution to privacy and confidentiality issues. Synthetic data can unlock previously inaccessible data sets for exploratory analysis and facilitate multiteam or multicenter collaborations. Interested sport scientists, practitioners, and researchers should consider utilizing the shiny web application (SYNTHETIC DATA-available at https://assetlab.shinyapps.io/SyntheticData/).

Early Success is not a Prerequisite for Success at the Adult Age in Spanish Sprinters

The aim of the study was to describe the relationship between success in junior and senior categories in sprint events. An observational and longitudinal analysis was carried out using rankings of the Royal Spanish Athletics Federation database. We analysed 547 sprinters (238 women and 309 men) from their U14 to senior stage who ranked in top-20 on at least one occasion during the period 2004 to 2021. The first entry in top-20 occurred mostly in U14 (44.4%, 243), and the frequency was progressively lower: 26.7% (146) in U16; 20.8% (114) in U18; 5.1% (28) in U20; 2% (11) in U23; and 0.9% (5) in the senior category. A similar tendency was observed in male and female athletes. Only 3.8% (9) of top-20 U14 athletes reached the senior elite stage, increasing this percentage in subsequent categories: 7.4% (15) in U16; 10.6% (24) in U18; 20.9% (32) in U20, and 31.4% (32) from U23 to the senior category. Data from female athletes showed higher maintenance of top-20 status from early categories to senior age. We conclude that even though the first entry into the national top-20 in sprint events occurs early in most cases, success in these initial stages is not a prerequisite for reaching top-20 positions in the senior category.

Concurrent Validity and Reliability of the Sprint Force-Velocity Profile Assessed with K-AI Wearable Tech

Establishing a sprint acceleration force-velocity profile is a way to assess an athlete's sprint-specific strength and speed production capacities. It can be determined in field condition using GNSS-based (global navigation satellite system) devices. The aims of this study were to (1) assess the inter-unit and the inter-trial reliability of the force-velocity profile variables obtained with K-AI Wearable Tech devices (50 Hz), (2) assess the concurrent validity of the input variables (maximal sprint speed and acceleration time constant), and (3) assess the validity of the output variables (maximal force output, running velocity and power). Twelve subjects, including one girl, performed forty-one 30 m sprints in total, during which the running speed was measured using two GPS (global positioning system) devices placed on the upper back and a radar (Stalker® Pro II Sports Radar Gun). Concurrent validity, inter-device and inter-trial reliability analyses were carried out for the input and output variables. Very strong to poor correlation (0.99 to 0.38) was observed for the different variables between the GPS and radar devices, with typical errors ranging from small to large (all < 7.6%). Inter-unit reliability was excellent to moderate depending on the variable (ICC values between 0.65 and 0.99). Finally, for the inter-trial reliability, the coefficients of variation were low to very low (all < 5.6%) for the radar and the GPS. The K-AI Wearable Tech used in this study is a concurrently valid and reliable alternative to radar for assessing a sprint acceleration force-velocity profile.

Effects of Complex Training on Jumping and Change of Direction Performance, and Post-Activation Performance Enhancement Response in Basketball Players

Exercise order is one of the significant factors modulating training effects. Therefore, the aim of this study was to compare the effectiveness of an 8-week complex (CPX) training program utilizing intra-CPX active recovery with compound training (CMP) on bilateral and single-leg jumping performance, change of direction test time (shuttle test), and the post-activation performance enhancement (PAPE) response in a group of basketball players. Thirteen participants were performing CPX bi-weekly combined with regular pre-season basketball practice, while eleven participants were performing CMP for 8 weeks. Before and after the interventions, the following fitness tests were assessed: (i) bilateral countermovement jump, (ii) single-leg countermovement jump, (iii) shuttle run test. All tests were performed pre- and post-conditioning activity (CA-three sets of five drop jumps). The results showed a statistically significant increase in non-dominant (p = 0.019) and dominant single-leg jump relative peak power (p = 0.001), and in non-dominant single-leg jump height (p = 0.022) post-training compared to pre-training. The CA was significantly and similarly effective in eliciting a PAPE response in all tests before and after each intervention (p < 0.039; for all). However, the magnitude of improvement in CMJ and shuttle test time was trivial to small and did not reach statistical significance. Both 8 weeks of CPX and CMP training led to significant improvements in the SLJ power output of both the dominant and non-dominant limbs as well as the height of the non-dominant SLJ. Neither of the training methods had significant impacts on the magnitude of the PAPE response.

Perfectionism and performance in a trail running competition: a prospective study of the interactive effects of perfectionism

Several studies explored the links between perfectionism and sport performance. However, only a few studies examined this relationship in the context of real sport competition and with a focus on the possible interactive effects of the dimensions of perfectionism. The present study aimed to investigate whether the two higher-order dimensions of perfectionism - perfectionistic strivings and perfectionistic concerns - interact in predicting performance in mountain trail running competitions. 167 athletes (54 females, 113 males) aged 19 to 65 (M = 39.32, SD = 9.35) completed measures of perfectionism in the week prior to the competition. Regression analyses revealed that perfectionistic strivings were a positive predictor of the runners' performance while perfectionistic concerns showed no significant associations with performance. However, a more in-depth exploration within the framework of the 2 × 2 model of perfectionism showed that the beneficial effects of high perfectionistic strivings are no longer significant when accompanied by high levels of perfectionistic concerns. These results support the notion that perfectionistic concerns may be detrimental to sport performance even if their overall, direct effects are not significant, adding first evidence of the existence of standard but also flipped perfectionistic tipping points in the context of sport performance.

The Effects of Nitrate Supplementation on Performance as a Function of Habitual Dietary Intake of Nitrates: A Randomized Controlled Trial of Elite Football Players

Nitrates are an effective ergogenic supplement; however, the effects of nitrate supplements based on habitual dietary nitrate intake through diet alone are not well understood. We aimed to assess this in a group of 15 highly trained football players from Slovenian football's First Division. Participants underwent two separate Cooper performance tests either with nitrate supplementation (400 mg nitrates) or placebo while having their nutrition assessed for nitrate intake, as well as energy and macronutrient intake. Nitrate supplementation had a statistically significant positive effect on performance if baseline dietary nitrate intake was below 300 mg (p = 0.0104) in both the placebo and intervention groups. No effects of nitrate supplementation when baseline dietary nitrate intake was higher than 300 mg in the placebo group could be concluded due to the small sample size. Nitrate supplementation did not have a significant effect on perceived exertion. The daily nitrate intake of the participants was measured at 165 mg, with the majority of nitrates coming from nitrate-rich vegetables.

Impacts of mental fatigue and sport specific film sessions on basketball shooting tasks

PURPOSE

The aim of this investigation was to examine the impact of mental fatigue on basketball specific shooting performance, utilising the newly developed basketball Standardized Shooting Task (SST).

METHODS

Fifteen male elite NCAA Division 1 collegiate basketball players (Age 20.2 ± 1.2 y, height 199.3 ± 7.1 cm, body mass 93.1 ± 8.6 kg) volunteered to participate in a randomised, counterbalanced crossover design undergoing three conditions (Control, Stroop, and Film). The task, performed on three consecutive days, was comprised of 60 free throw attempts followed by a 4-minute spot-to-spot shooting.

RESULTS

Visual Analog Scales revealed significantly higher levels of mental fatigue following the Stroop (54.2 ± 24.5) condition compared to the Control (24.5 ± 16.2) and higher levels of mental effort in the Stroop (61.0 ± 31.3) and Film (49.9 ± 27.7) compared to the Control (14.0 ± 18.5). No significant differences were observed for Motivation among groups (p > 0.05). There was a significant decrease (p = 0.006) in number of shots made in 4-minutes (MAKE4MIN; control = 49.5 ± 10.2, Stroop = 44.0 ± 10.6, and Film = 45.1 ± 11.7) and shots missed in 4-minutes (MISS4MIN; control = 27.3 ± 7.0, Stroop = 30.9 ± 7.1, and Film = 30.9 ± 7.6). No significant differences were detected for any other performance variables.

CONCLUSION

These data demonstrate that mental fatigue negatively impacts basketball shooting performance in elite collegiate basketball players. We suggest that practitioners and coaches encourage athletes to abstain from cognitively demanding tasks prior to basketball competition.

Effects of Continuous Carbohydrate Intake with Gummies during the Golf Round on Interstitial Glucose, Golf Performance, and Cognitive Performance of Competitive Golfers: A Randomized Repeated-Measures Crossover Design

This study examined the effects of continuous carbohydrate intake during a golf round on interstitial glucose, golf performance, and the cognitive performance of competitive golfers. Eleven competitive golfers participated and played 18 holes of golf in this study. Participants were randomly assigned to the group indicated to consume the test food (CHO intake) or the group required to not consume it (NOT intake). Here, gummies were used as the test food, and the amount of carbohydrates was 30 g per h. Blood glucose levels were evaluated using interstitial glucose. Golf performance was measured in five tests, including scores, 2.5 m putting test, club head speed, driving distance, and accuracy. Cognitive performance was measured in three tests, including self-perceived levels of fatigue (PLF), self-perceived levels of concentration (PLC), and self-perceived levels of relaxation (PLR). Interstitial glucose (p < 0.001) and PLF (p < 0.001) were significantly reduced in the CHO intake compared with that in the NOT intake from the sixth hole. PLC was significantly higher in the CHO intake than in the NOT intake on all 18 holes (p = 0.032). These findings suggest that continuous carbohydrate intake may be effective in reducing fatigue and maintaining the performance of competitive golfers.

The Relationships Between Neural Activity and In-Game Hitting Performance in Baseball

The current study examines the relationships between hitters' neural activity and their in-game hitting performance. Collegiate baseball players completed a computerized video task assessing whether thrown pitches were balls or strikes while their neural activity was recorded. In addition, each player's hitting statistics were collected for the following baseball season. Results showed that neural activity during the computerized task was associated with in-game hitting performance, even after accounting for other individual difference variables. These findings indicate that players' neural activity measured in a laboratory environment shows a translational relationship with in-game hitting performance over time. Neural activity provides a more objective analysis of players' ongoing self-regulatory processes during hitting and a better understanding of the cognitive processes associated with hitting performance. Self-regulatory cognitive control is adaptable and trainable, and this research advances the measurement of cognitive variables related with in-game hitting performance in baseball.

Effects of emotional regulation and impulsivity on sports performance: the mediating role of gender and competition level

Introduction

This study aimed to study the relationships between emotional regulation and impulsivity on sports performance, according to the gender and competition level in national-level volleyball players.

Methods

In total, 77 players from the 2018-2019 top two Spanish divisions completed the ERQ (emotion regulation) and the UPPS-P (impulsivity). Statistics (serve, reception, and attack) were retrieved from the Spanish Volleyball Federation. A Mann-Whitney test was conducted to determine differences between gender and competition level in impulsivity and emotion regulation. A Kruskal-Wallis test (Mann-Whitney post-hoc) was carried out for playing positions analysis. Spearman's correlation was performed between the performance and the variables of impulsivity and emotional regulation.

Results

The results obtained, with differences according to playing position, gender, and competition level, show that players differ in certain psychological aspects that might influence how they approach their game.

Discussion

The results point in a promising direction: the sports practice analyzed can serve as a regulation context, for both the emotional response and the level of impulsivity of the players. The importance of these results for future research on this topic is discussed.

The effects of a land-based home exercise program on surfing performance in recreational surfers

Surfing has become a popular, non-age dependent sport that can be performed at most beaches. Hence, coaches and athletes have recognised the importance of physical preparation to enhance athletic performance. The purpose of this study was to investigate the effects of a sport-specific, land-based-home exercise programme (LB-HEP) on sport-specific assessments related to surfing performance in recreational surfers. Twenty-two year-round recreational surfers divided into two groups: the exercise group (EG) performed the LB-HEP 3 times a week for 8 weeks while the control group (CG) maintained their current exercise. Both groups were instructed to continue surfing during the study period. Each surfer completed sport-specific measurements related to surfing demands both pre-test and post-test (8 weeks). There was a significant interactive effect of time and group (p = .009, η_p² =.298) on the surfer's performance questionnaire showing greater improvements in the EG. Additionally, the EG had an improvement on time to pop-up when compared to the CG (η_p² =.160). Based on the results, the LB-HEP is an effective training programme for all experience levels of recreational surfers to improve surfing performance measures short term.

Equine Behavioural and Physiological Responses to Auditory Stimuli in the Presence and Absence of Noise-Damping Ear Covers

Despite numerous studies investigating responses to visual perception, there is limited research into how horses respond to different auditory stimuli. Although 'noise-damping' ear covers are frequently used on sport horses to minimise distraction from external auditory stimuli, the effectiveness of ear covers has not been established. This study aimed to (i) investigate the responses of horses to different sounds commonly present in a competition environment, and (ii) compare these responses in the presence and absence of ear covers. A total of 18 horses were presented with 5 sounds commonly heard in competition or stable environments both with and without ear covers, in a randomised order crossover design. Behavioural and heart rate responses were recorded. Responses were compared between sounds and with/without ear covers. Differences in physiological and behavioural responses to different complex auditory stimuli were shown. An overall difference in physiological and behavioural responses with and without ear covers was detected, although the only difference in heart rate between ear covers and no ear covers that individually achieved significance was the feed sound. These findings suggest that horses can discriminate sounds and alter their responses based on the individual stimulus, and these responses are reduced when wearing ear covers with varying effectiveness for different sounds.

Comparison of Psychological Readiness to Return to Sport After Primary Versus Revision Anterior Cruciate Ligament Reconstruction

Background

Rates of return to preinjury level of play after anterior cruciate ligament (ACL) reconstruction (ACLR) remain unsatisfactory, particularly for patients who undergo revision surgery. Psychological readiness is associated with successful return to sport (RTS) and self-perceived preinjury sport performance.

Purpose

To compare psychological readiness at RTS between patients who underwent revision ACL autograft reconstruction and matched controls who underwent primary ACL autograft reconstruction.

Study Design

Cohort study; Level of evidence, 3.

Methods

Data were gathered using a single orthopaedic surgeon database of patients who underwent ACLR between 2015 and 2018. Patients who underwent revision ACLR and met the study criteria (N = 92) were matched by age, sex, graft type, and rehabilitation protocol to a control group of patients who underwent primary ACLR (n = 92). Functional assessment at release to play was examined using passive knee range of motion, single-leg squat, and single-leg hop testing. Self-reported outcomes included the International Knee Documentation Committee subjective function survey and the ACL-Return to Sport after Injury (ACL-RSI) psychological readiness scale. Time to release to play was recorded as the number of months needed to reach a ≥90% limb symmetry index from the date of the index ACLR. Data were assessed for normality using the Shapiro-Wilk test, and univariate general linear models were utilized with an alpha level of .05.

Results

The overall mean patient age was 29.9 ± 10 years, and 40% of patients were women. No significant differences between groups were noted in any of the baseline patient characteristics or surgical findings. At RTS, the mean ACL-RSI score was significantly lower in the revision surgery group (77.4 ± 19.4 vs 85.3 ± 17.4; P = .011). In addition, the revision surgery group returned to play significantly later than the primary surgery group (9.4 ± 2 vs 8.1 ± 1.3 months, respectively; P < .001).

Conclusion

When compared with primary ACL autograft reconstruction, revision reconstruction patients exhibited lower psychological readiness scores and a longer time to meet the objective criteria for RTS.

Registration

NCT03704376 (ClinicalTrials.gov identifier).

Mental Fatigue From Smartphone Use or Stroop Task Does Not Affect Bench Press Force-Velocity Profile, One-Repetition Maximum, or Vertical Jump Performance

The aim of this study was to explore the effects of mental fatigue from smartphone use and Stroop task on bench press force-velocity (F-V) profile, one-repetition maximum (1RM), and countermovement jump (CMJ) performance. Twenty-five trained subjects (age = 25.8 ± 5.7 years) completed three sessions separated by 1 week following a randomized double-blinded crossover design. Each session consisted of F-V relationship, 1RM, and CMJ measurements after performing 30 min of control, social media, or Stroop task. Perceived mental fatigue and motivation were recorded. Mental fatigue, motivation, CMJ height, bench press 1RM, and F-V profile variables (maximal force, maximal velocity, and maximal power) were compared between interventions. Significant differences were found for mental fatigue between interventions (p ≤ .001). Both ST (p ≤ .001) and SM (p = .007) induced higher mental fatigue than control. However, no significant differences between interventions were observed for any other variable (p = .056-.723). The magnitude of the differences between interventions ranged from negligible to small (effect sizes ≤ 0.24). These results suggest that although both ST and SM were effective to induce mental fatigue, neither ST nor SM affected CMJ performance, bench press 1RM, or any variable of the F-V profile compared with the control task.

Dietary Nitrate Ingestion Does Not Improve Neuromuscular Performance in Male Sport Climbers

Beetroot juice (BJ) is commonly used as an ergogenic aid in endurance and team sports, however, the effect of this supplement on climbing performance is barely studied. The purpose of the current study was to investigate the effect of acute BJ ingestion on neuromuscular and biochemical variables in amateur male sport climbers. Ten physically active sport climbers (28.8 ± 3.7 years) underwent a battery of neuromuscular tests consisting of the half crimp test, the pull-up to failure test, the isometric handgrip strength test, the countermovement jump (CMJ) and the squat jump (SJ). Participants performed the neuromuscular test battery twice in a cross-over design separated by 10 days, 150 min after having consumed either 70-mL of BJ (6.4 mmol NO_3-) or a 70-mL placebo (0.0034 mmol NO_3-). In addition, nitrate (NO_3-) and nitrite (NO_2-) saliva concentrations were analysed, and a side effect questionnaire related to ingestion was administrated. No differences were reported in particular neuromuscular variables measured such as the CMJ (p = 0.960; ES = 0.03), the SJ (p = 0.581; ES = -0.25), isometric handgrip strength (dominant/non dominant) (p = 0.459-0.447; ES = 0.34-0.35), the pull-up failure test (p = 0.272; ES = 0.51) or the maximal isometric half crimp test (p = 0.521-0.824; ES = 0.10-0.28). Salivary NO_3- and NO_2- increased significantly post BJ supplementation compared to the placebo (p < 0.001), while no side effects associated to ingestion were reported (p = 0.330-1.000) between conditions (BJ/placebo ingestion). Acute dietary nitrate supplementation (70-mL) did not produce any statistically significant improvement in neuromuscular performance or side effects in amateur sport climbers.

The Influence of Emotional Intelligence on Coping Ability in Senior Female Field-Hockey Players in South Africa

Research has suggested that coping under pressure could be rooted in the ability to identify and manage one's emotions. In this study, we investigated this hypothesis using cross-sectional data obtained from a sample of South African national and university level female field-hockey players (N = 60, Mage = 21.57, SD = 3.65). A correlational research design was adopted of which a pen-and-paper survey containing the Emotional Intelligence Scale and Athletic Coping Skills Inventory-28 was used to collect the data. Descriptive results exposed players to yield higher than average levels of total emotional intelligence and coping ability in sport with significant differences noted between the national and university level players in terms of their ability to manage their own emotions (p = 0.018), utilise emotions (p = 0.007, d = 0.74), coping with adversity (p = 0.002, d = 0.84), coachability (p < 0.01, d = 3.17), and overall coping ability (p < 0.01, d = 1.00). After controlling for the level of participation, hierarchical linear regression analyses confirmed the relationship between the study variables exposing total emotional intelligence to be a significant predictor of players' ability to cope with adversity (β = 0.55, p = 0.006), concentrate (β = 0.43, p = 0.044), maintain confidence and achievement motivation (β = 0.42, p = 0.027), as well as overall coping ability (β = 0.28, p = 0.023). It was concluded that emotional intelligence may be a worthy contributor in the psychological profiling of players and a plausible intervention mapping tool in sport psychology practice to potentially enhance the coping ability of female field-hockey players.

School Attendance, Chronotype, and Day-of-the-Week Effect in Adolescent Male Basketball Players

Adolescents' conflict between circadian rhythm and early school start time is more pronounced in evening chronotypes, who tend to reduce sleep duration during school days compensating during the free days by oversleeping (i.e., social jetlag). Cumulative weekly sleep debt may impair sport performance, which relies on physical and cognitive skills modulated by sleep. We hypothesized that chronotype predicts sport performance, and that it may interact with the day of the week. Moreover, given the role sleep plays in motor memory consolidation, we tested the hypothesis that school attendance, and the related chronic sleep deprivation, might be detrimental for participants in a training phase. Ninety-three adolescent male basketball players performed multiple free throw sessions (n = 7880) during both the school and holiday periods. Chronotype and its interaction with the day of the week significantly predicted shooting accuracy when attending school, but not on holidays. Evening types' performance gradually decreased from Monday to Friday. Participants with a more unstable performance (i.e., who did not complete the acquisition of the free throw motor scheme) worsened their accuracy when attending school. Our results suggest that the impact of chronotype and day of the week on sport performance is related to the presence of an externally imposed sleep/wake schedule and is consistent with evening types' increased likelihood of experiencing social jetlag. Possibly due to early school start time, attending school worsened the performance of participants in a training phase. Further investigations are required to assess whether reducing the mismatch between biological and social clocks might improve sport performance, along with other aspects of adolescents' life.

Handling shifts during an overnight sailing regatta: Comparison between sleep management strategies

The study aims to investigate the association between different sleep management strategies and the final ranking during a one-night sailing race. A large sample of 190 teams participating in the overnight sailing regatta (151 Miglia) were included in the study. The experimental design consisted of two surveys, administered one before the start of the race and the other after the arrival. The questionnaires provided general information on the sailboat, its crew, and the strategy adopted to manage sleep during the race. In this one-night regatta, the self-management of sleep/wake timing emerged as the most successful strategy. Among participants who adopted a shift-based racing strategy, a short night shift duration (i.e., 2 h) significantly predicted a better placement. These findings confirmed the relevance of sleep management in sport performance and provided new insights into the most suitable sleep management strategy during a relatively short offshore regatta. The conclusions might apply also to similar continuous-cycle activities. Further investigations are needed to explore best sleep management strategy in team regattas of longer duration.

Offset Loading in a Bilateral Squatting Movement Pattern Influences Ground-Reaction Force and Muscle Activity in the Dominant and Nondominant Limb

PURPOSE

The purpose of this study was to explore whether offset loading in the barbell squat altered ground-reaction force (GRF) and muscle activation in the dominant (D) and nondominant (ND) lower limb compared to traditional squats.

METHODS

Twelve well-trained men (age 26.4 [3.2] y; 10.3 [1.9] y experience) performed 3 sets of 10 repetitions at 60% of their previously measured 1-repetition maximum. Sets were quasi-randomized between traditional loading (TDL), dominant-side offset loading (OS-D), and nondominant-side offset loading (OS-ND). All repetitions were performed on a dual force plate with electromyography sensors on the prime mover muscles of the squat. GRF symmetry was assessed using the symmetry index (SI) to determine the direction (D [+] or ND [-]) and magnitude (%) of the asymmetry. Finally, the first 3 and final 3 repetitions of each set were compared for compensatory changes in symmetry.

RESULTS

OS-D induced a significant change in limb SI relative to TDL (5.21% vs 1.44%; P = .011); however, no significant difference in limb SI was seen between TDL and OS-ND (-0.66% vs 1.44%; P = .278). No asymmetries between D and ND muscle activation were present in any condition. TDL and OS-D squats exhibited significant improvements in limb SI between the first 3 and final 3 repetitions (P = .035 and .011, respectively); however, no such improvement was seen in OS-ND.

CONCLUSIONS

OS-D is capable of significantly altering GRF limb SI in a bilateral squat; however, OS-ND appears to exhibit no GRF or electromyography effects relative to TDL. Thus, the results of this study do not support the use of OS-ND in the pursuit of strengthening a weaker limb, suggesting that unilateral training may be a preferred mode of exercise for this desired outcome.

QEEG markers of superior shooting performance in skilled marksmen: An investigation of cortical activity on psychomotor efficiency hypothesis

For elite performers, psychomotor behavior's success or failure can be traced to differences in brain dynamics. The psychomotor efficiency hypothesis suggests refined cortical activity through 1) selective activation of task-relevant processes and 2) inhibition of non-essential processes. The use of electroencephalography (EEG) has been applied to investigate psychomotor performance's neural processes. The EEG markers that reflect an elevation of psychomotor efficiency include left temporal alpha (T3 alpha), frontal midline theta (Fm theta), sensorimotor rhythm (SMR), and the coherence between frontal and left temporal regions. However, the relationship between elite performers' task-relevant and non-essential neural processes is still not well understood. Therefore, this study aimed to explore how each task-relevant and inhibition of non-essential processes contribute to superior psychomotor behavior. Thirty-five highly skilled marksmen were recruited to perform 30 shots in the shooting task while the EEG was recorded. The marksmen were divided into two groups (superior & inferior) based on a median split of shooting performance. The superior group exhibited higher accuracy and precision, with a reduction in movement jerk. EEG measures revealed that the superior group exhibited higher SMR before the trigger pull than the inferior group. In addition, the superior group demonstrated reduced Fz-T3 coherence in their bull's eye shots than the missed shots. These results suggest that the superior group exhibited less effortful engagement of task-relevant processes and lower interference from non-essential cortical regions than the inferior group. The study's overall findings support the psychomotor efficiency hypothesis. When comparing highly skilled performers, the slight differences in brain dynamics ultimately contribute to the success or failure of psychomotor performance.

Key performance indicators of Olympic windsurfers during a World Cup: RS:X class®

The aim of this study was to analyse differences in velocity, distance travelled and manoeuvres performed by Olympic sailors of the RS:X class using a GPS device. Fifty-three Olympic sailors of the RS:X class (28 males and 25 females) who competed in a World Championship were selected. The sample was divided into tertiles (T1, T2 and T3) according to their classification in the competition. Using a GPS device during the competition, mean velocity (VM), velocity made good (VMG), manoeuvres and distances in three different courses (upwind, reaching and downwind) were assessed during a regatta. Significant differences were found based on performance level in upwind (p < 0.001; ηp2 = 0.288), sailors of T1 covering a shorter distance compared to those of T2 (p < 0.009) and T3 (p < 0.001). Regarding VMG, an effect was observed for performance level in upwind (p < 0.001; ηp2 = 0.718), reaching (p < 0.001; ηp2 = 0.469) and downwind (p < 0.001; ηp2 = 0.575). Females covered a shorter distance compared to the males in upwind (p < 0.001; ηp2 = 0.639) and downwind (p < 0.001; ηp2 = 0.903). Distance and VMG are significant variables for establishing differences in performance level among Olympic sailors of the RS:X class when the wind speed is in a range of 8-21 knots.

Match Load Physical Demands in U-19 Professional Soccer Players Assessed by a Wearable Inertial Sensor

BACKGROUND

Wearable inertial sensors are poorly used in soccer to monitor external load (EL) indicators. However, these devices could be useful for improving sports performance and potentially reducing the risk of injury. The aim of this study was to investigate the EL indicators (i.e., cinematic, mechanical, and metabolic) differences between playing positions (i.e., central backs, external strikers, fullbacks, midfielders, and wide midfielder) during the first half time of four official matches (OMs).

METHODS

13 young professional soccer players (Under-19; age: 18.5 ± 0.4 years; height: 177 ± 6 cm; weight: 67 ± 4.8 kg) were monitored through a wearable inertial sensor (TalentPlayers TPDev, firmware version 1.3) during the season 2021-2022. Participants' EL indicators were recorded during the first half time of four OMs.

RESULTS

significant differences were detected in all the EL indicators between playing positions except for two of them (i.e., distance traveled in the various metabolic power zones (<10 w) and the number of direction changes to the right >30° and with speed >2 m). Pairwise comparisons showed differences in EL indicators between playing positions.

CONCLUSIONS

Young professional soccer players showed different loads and performances during OMs in relation to playing positions. Coaches should consider the different physical demands related to playing positions in order to design the most appropriate training program.

Sport and mental health performance optimization in an adolescent gymnast: A case evaluation

The Optimum Performance Program in Sports (TOPPS) is a multi-component, sport-specific Family Behavior Therapy that has demonstrated improved sport performance, relationships, and mental health outcomes in adult and adolescent athletes with, and without, diagnosed mental health disorders in clinical trials. The current case trial demonstrates successful implementation of a novel component of TOPPS (i.e., talk aloud optimal sport performance imagery leading to dream mapping) in a biracial Latina and White adolescent gymnast without a mental health diagnosis. The participant demonstrated significant improvements from baseline to both post-treatment and 3-month follow-up in severity of mental health functioning, factors interfering with sports performance, and her relationships with teammates, coaches, and family. Results suggest it may be possible to optimize mental health through sport performance optimization.

Relationship between Maximum Force-Velocity Exertion and Swimming Performances among Four Strokes over Medium and Short Distances: The Stronger on Dry Land, the Faster in Water?

Evaluating force-velocity characteristics on dry-land is of the utmost importance in swimming, because higher levels of these bio-motor abilities positively affect in-water performance. However, the wide range of possible technical specializations presents an opportunity for a more categorized approach that has yet to be seized. Therefore, the aim of this study was to identify feasible differences in maximum force-velocity exertion based on swimmers' stroke and distance specialization. To this scope, 96 young male swimmers competing at the regional level were divided into 12 groups, one for each stroke (butterfly, backstroke, breaststroke, and front crawl) and distance (50 m, 100 m, and 200 m). They performed two single pull-up tests, 5-min before and after competing in a federal swimming race. We assessed force (N) and velocity (m/s) exertion via linear encoder. There were no significant differences between pre-post maximum force-velocity exertions, despite the decreasing trend. Force-parameters highly correlated with each other and with the swimming performance time. Moreover, both force (t = -3.60, p < 0.001) and velocity (t = -3.90, p < 0.001) were significant predictors of swimming race time. Sprinters (both 50 m and 100 m) of all strokes could exert significantly higher force-velocity compared to 200 m swimmers (e.g., 0.96 ± 0.06 m/s performed by sprinters vs. 0.66 ± 0.03 m/s performed by 200 m swimmers). Moreover, breaststroke sprinters presented significantly lower force-velocity compared to sprinters specialized in the other strokes (e.g., 1047.83 ± 61.33 N performed by breaststroke sprinters vs. 1263.62 ± 161.23 N performed by butterfly sprinters). This study could provide the foundation for future research regarding the role of stroke and distance specializations in modeling swimmers' force-velocity abilities, thus influencing paramount elements for specific training and improvement towards competitions.

Dynamic Visual Acuity After Small Incision Lenticule Extraction for Myopia Patients

In the present study we compared dynamic visual acuity (DVA) of 84 eyes (for 42 adults with myopia; M age = 28.4, SD = 6.6 years; males = 38.1%, females = 61.9%) at 40 and 80 degree per second (dps) before surgery with eyeglass corrections and after a surgical procedure - a small incision lenticule extraction (SMILE). Participants underwent binocular SMILE surgery with plano refraction targets. Their eyeglass-corrected binocular DVA at 40 and 80 dps was evaluated preoperatively, and their uncorrected binocular DVA was assessed post-operatively at 1 week, 1 month and 3 months. The mean logMAR (logarithm of the minimum angle of resolution) uncorrected and corrected distance visual acuities (UDVA and CDVA) were -0.09 and -0.11 respectively, 3 months postoperatively. The mean preoperative eyeglass-corrected DVAs at 40 and 80 dps were 0.141 and 0.184, respectively, and significant improvements were observed for 40 dps and 80 dps DVAs 3 months postoperatively. Pearson's correlations were statistically significant between the postoperative DVAs at 3 months and for both the preoperative DVA and postoperative UDVA at both 40 dps and 80 dps. The change in the DVAs at 3 months were significantly associated with the preoperative DVAs at 40 dps and 80 dps. In conclusion, myopic patients' DVAs significantly improved following SMILE in comparison to corrected preoperative visual acuity when wearing eyeglasses. The post-SMILE DVA was associated with both the preoperative DVA and the postoperative UDVA.