scholarly journals Analysis of the Association Between Motor and Anthropometric Variables with Change of Direction Speed and Reactive Agility Performance

2015 ◽  
Vol 47 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Tine Sattler ◽  
Damir Sekulić ◽  
Miodrag Spasić ◽  
Mia Perić ◽  
Ante Krolo ◽  
...  
Keyword(s):  
Body Mass ◽  
Body Height ◽  
Male Body ◽  
College Level ◽  
F Test ◽  
Change Of Direction ◽  
Stop And Go ◽  
Significant Difference ◽  
Reactive Agility ◽  
Males And Females

AbstractThere is an evident lack of studies examining the factors associated with reactive agility performances. The aim of this study was to evaluate the association between anthropometrics, body composition, jumping capacity, reactive strength, and balance with a stop-and-go change of direction speed (CODS) and reactive agility. The total sample comprised 39 male (body height: 182.95 ± 5.19 cm; body mass: 80.66 ± 7.69 kg) and 34 female (body height: 171.45 ± 6.81 cm; body mass: 61.95 ± 6.70 kg) college-level athletes (21.9 ± 1.9 years of age). The variables included body height, body mass, the percentage of body fat (BF%), balance as measured by an overall-stability index, the countermovement jump (CMJ), a reactive-strength index (RSI), stop-and-go reactive agility, and stop-and-go CODS. To define the associations between motor and anthropometric variables with CODS and reactive agility, the participants were clustered into three achievement groups based on their CODS and reactive agility performances. The ANOVA showed a significant difference between the CODS-based achievement groups for the CMJ (F test = 3.45 and 3.60 for males and females, respectively; p < 0.05), the RSI (F test = 6.94 and 5.29 for males and females, respectively; p < 0.05), and balance (F test = 3.47; p < 0.05 for males). In females, the reactive agility achievement groups differed significantly in the RSI (F test = 6.46; p < 0.05), the CMJ (F test = 4.35; p < 0.05) and BF% (F test = 4.07; p < 0.05), which is further confirmed by discriminant canonical analysis (Can R = 0.74; p < 0.05). The results confirm the need for independent evaluation and training for both CODS and reactive agility performance in sports.

scholarly journals The Relationship Between Reactive Agility and Change of Direction Speed in Professional Female Basketball and Handball Players

2021 ◽  
Vol 12 ◽  
Author(s):  
Marek Popowczak ◽  
Ireneusz Cichy ◽  
Andrzej Rokita ◽  
Jarosław Domaradzki
Keyword(s):  
Body Mass ◽  
Body Height ◽  
Anthropometric Parameters ◽  
Basketball Players ◽  
Change Of Direction ◽  
Significant Difference ◽  
Anthropometric Features ◽  
Reactive Agility ◽  
Partial Correlations ◽  
The Difference

Assessing the physical ability of players to perform change of direction and the cognitive and motor abilities revealed in reactive agility (RA) is necessary to understand the physical requirements and capabilities of professional players in handball and basketball. The main aim of this study was to determine the differences between professional female basketball and handball players in terms of anthropometric features, change of direction speed (CODS), and the RA task. Moreover, the relationships among anthropometric features, agility, and parameters of perception were determined. Two scenarios of the Five-Time Shuttle Run to Gates test (planned and unplanned) were used to evaluate the CODS and RA. The response time (RT) was also measured in the unplanned scenario. Additionally, the index of reactivity (REAC-INDEX) was specified as the difference between the RA test result and the measurement of CODS. There was a significant difference found in terms of body height, with basketball players being taller than handball players (p = 0.032). Professional female handball players achieved better results than professional female basketball players with regard to RA tasks (p = 0.01) and CODS (p = 0.041). Significant simple correlations between each anthropometric feature (body height, body mass) and values for CODS and RA were observed (r = 0.49–0.53). Applying partial correlation allowed for the assessment of actual relationships among CODS, RA, RT, and REAC-INDEX, without a confounding variable. Detaching the anthropometric parameters from the rest of the relationships resulted in maintenance or changes in r-values and an increased significance in the relationships between each pair: RA vs. RT, RA vs. REAC-INDEX, and RT vs. REAC-INDEX. The strongest associations were related to RT vs. REAC-INDEX (r = 0.97 at detaching body height or body mass, p &lt; 0.001) and CODS vs. RA (r = 0.66 at detaching body height and r = −0.67 at detaching body mass, p &lt; 0.001). It is recommended to use partial correlations in subsequent studies, as simple correlations are not reliable and may not reveal the apparent relationships between the variables. In addition, when determining the CODS and RA, it is suggested to take anthropometric and perception variables into account, such as reaction time or REAC-INDEX.

scholarly journals Importance of Agility Performance in Professional Futsal Players; Reliability and Applicability of Newly Developed Testing Protocols

2019 ◽  
Vol 16 (18) ◽  
pp. 3246 ◽  
Author(s):  
Damir Sekulic ◽  
Nikola Foretic ◽  
Barbara Gilic ◽  
Michael R. Esco ◽  
Raouf Hammami ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Body Height ◽  
T Test ◽  
Effect Sizes ◽  
Change Of Direction ◽  
Reactive Agility ◽  
Testing Protocols ◽  
Level Group ◽  
Dominant Side

The purpose of this study was to determine the inter- and intra-testing reliability of newly developed tests of the change of direction speed (CODS) and reactive agility (RAG) in competitive futsal players. Additionally, the developed tests were evaluated for their validity with regard to the differentiation of two performance-levels. Thirty-two professional male futsal players (age = 26.22 ± 5.22 years; body height = 182.13 ± 5.99 cm, body mass = 77.43 ± 8.00 kg) participated in the study. The sample was divided into two groups based on their level of futsal performance: A top-level-group (n = 12) and a team-level-group (n = 20). The variables included body height, mass, body mass index, a sprint over a 10-m distance (S10M), and eight newly developed futsal specific CODS and RAG tests. The CODS and RAG tests were performed by dribbling the balls (CODS_D and RAG_D) and without dribbling (CODS_T and RAG_T), and the performances on the dominant and non-dominant sides were observed separately. All CODS, and RAG tests performed on dominant side and RAG_T tests performed on the non-dominant side had good inter-testing (CV = 5–8%; ICC = 0.76–0.89) and intra-testing (CV = 4–9%; ICC = 0.77–0.91) reliability. However, RAG_D performed on the non-dominant side was not reliable (ICC = 0.60, CV = 10%). The top-level-players outperformed the team-level-players in the CODS and RAG tests that involved dribbling (t-test: 4.28 and 2.40, p < 0.05; effect sizes (ES): 0.81 and 1.5, respectively), while the team-level players achieved better results in the CODS_T (t-test: 2.08, p < 0.05; ES: 0.60). The proposed CODS and RAG tests that involved dribbling over a 3.2-m distance, especially on the dominant side, appeared to be reliable, as well as valid for distinguishing the performance level in futsal players.

Predicting futsal specific change of direction speed and reactive agility; analysis of specific correlates in top-level players

2020 ◽  
Author(s):  
Ivan Zeljko ◽  
Miodrag Spasic ◽  
Damir Sekulic
Keyword(s):  
Body Mass ◽  
Predictive Validity ◽  
Body Height ◽  
Negative Influence ◽  
Strength Index ◽  
Advanced Level ◽  
Change Of Direction ◽  
Reactive Agility ◽  
National Champions ◽  
Specific Influence

Purpose: Change of direction speed (CODS) and reactive agility (RAG) are important qual-ities in futsal, but studies rarely examined the predictors of these conditioning capacities in players of advanced level. This study aimed to evaluate predictive validity of certain an-thropometric and conditioning capacities in evaluation of futsal specific CODS and RAG in top-level players. Methods: The sample comprised 54 male players from Croatia and Bosnia and Herzegovina, members of teams competing at the highest national rank, including national champions for the 2017–2018 competitive season in both countries. The variables comprised set of pre-dictors (body mass, body height, triceps skinfold, reactive strength index [RSI], sprint 10 m [S10M], and broad jump [BJ]; and four criteria: futsal specific CODS and RAG, performed with and without dribbling (CODS_D, CODS_WD, RAG_D, RAG_WD). To identify the asso-ciation between variables Pearson’s correlation and multiple regressions were calculated. Results: Observed predictors explained statistically significant (p < 0.05) percentage of vari-ance for all four criteria (Rsq: 0.28, 0.30, 0.23 and 0.25, for CODS_WD, CODS_D, RAG_WD, RAG_D, respectively). Body mass was significant predictor for all criteria (Beta: 0.35–0.51), with poorer performances in heavier players. In both performances which involved dribbling, significant predictors was RSI (Beta: −0.27 and −0.31 for CODS_D and RAG_D, respective-ly), with superior performances in players with better RSI. The S10M and BJ were not identi-fied as being significantly correlated to studied RAG and CODS performances. Conclusion: Study confirmed specific influence of studied predictors of futsal specific CODS and RAG with consistent negative influence of body mass on studied performances. Almost certainly this can be explained by specifics of RAG and CODS execution. Specifically, tests are performed over relatively small distances, with several changes of direction, which clear-ly mimic the futsal specific performances. Although sprint performance is often observed as important determinant of CODS and RAG, herein we did not confirm its predictive validity in explanation of futsal specific CODS and RAG. Future studies should evaluate other poten-tially important predictors of these capacities in futsal.

Warm-Up With Dynamic Stretching: Positive Effects on Match-Measured Change of Direction Performance in Young Elite Volleyball Players

2020 ◽  
Vol 15 (4) ◽  
pp. 528-533
Author(s):  
Olfa Turki ◽  
Wissem Dhahbi ◽  
Johnny Padulo ◽  
Riadh Khalifa ◽  
Sana Ridène ◽  
...  
Keyword(s):  
Body Mass ◽  
Test Performance ◽  
Body Height ◽  
Performance Measurements ◽  
Fat Percentage ◽  
Warm Up ◽  
Dynamic Stretching ◽  
Change Of Direction ◽  
Positive Effects ◽  
Volleyball Players

Purpose: To explore the immediate (15-s post-warm-up) and the delayed (after 20 and 40 min of simulated volleyball play) effects of 2 different warm-up protocols—a stretching-free volleyball warm-up (NS) and a warm-up incorporating dynamic stretching (DS)—on subsequent change of direction (COD) performance in young elite volleyball players. Methods: Sixteen male players (age 16.88 [0.34] y, body mass 75.81 [5.41] kg, body height 1.91 [0.05] m, body mass index 20.84 [1.79] kg·m−2, and body fat percentage 9.48 [1.83]%) from the U-17 national volleyball team performed NS and DS on 2 different nonconsecutive days. During each testing session (NS and DS), half T-test performance measurements were performed after 5 minutes of a general warm-up (ie, baseline), immediately post-warm-up (after 15 s), and after 20 and 40 minutes of simulated volleyball play. Results: For DS, a significant improvement in COD performance (2.08%, P < .001) was observed after 20 minutes of play compared with the baseline values. In addition, COD performance recorded after 40 minutes of play was better than after 15-second post-warm-up (5.85%, P = .001). Inferential statistics showed better COD performance in the DS condition after 20 minutes of play (2.32%, likely negative, d = 0.61). Conclusions: Compared with NS, DS tended to affect the pattern of improvement of COD performance during play by intensifying and accelerating it. Consequently, to enhance COD performance for up to 40 minutes into the game, it is recommended that DS be incorporated to the warm-up preceding the match.

Dynamic Warm-Up With a Weighted Vest: Improvement of Repeated Change-of-Direction Performance in Young Male Soccer Players

2020 ◽  
Vol 15 (2) ◽  
pp. 196-203
Author(s):  
Olfa Turki ◽  
Wissem Dhahbi ◽  
Sabri Gueid ◽  
Sami Hmaied ◽  
Marouen Souaifi ◽  
...  
Keyword(s):  
Body Mass ◽  
Body Height ◽  
Soccer Players ◽  
Peak Time ◽  
Fatigue Index ◽  
Warm Up ◽  
Change Of Direction ◽  
Recovery Times ◽  
Weighted Vest ◽  
Weighted Vests

Purpose: To explore the effect of 4 different warm-up strategies using weighted vests and to determine the specific optimal recovery duration required to optimize the repeated change-of-direction (RCOD) performance in young soccer players. Methods: A total of 19 male soccer players (age 18 [0.88] y, body mass 69.85 [7.68] kg, body height 1.75 [0.07] m, body mass index 22.87 [2.23] kg·m−2, and body fat percentage 12.53% [2.59%]) completed the following loaded warm-up protocols in a randomized, counterbalanced cross-over, within-participants order and on separate days: weighted vest with a loading of 5% (WUV5%), 10% (WUV10%), 15% (WUV15%) body mass, and an unloaded condition (control). RCOD performance (total time, peak time, and fatigue index) was collected during the preintervention phase (5 min after the dynamic stretching sequence) for baseline values and immediately (at 15 min), at 4- and 8-minute postwarm-up intervention. Results: For each postwarm-up tested, recovery times (ie, 15 s, 4 min, and 8 min), of both total and peak times were faster following WUV5%, WUV10%, and WUV15%, compared with the unloaded condition (P ≤.001–.031, d = 1.28–2.31 [large]). There were no significant differences (P = .09–1.00, d = 0.03–0.72 [trivial–moderate]) in-between recovery times in both total and peak times following WUV5%, WUV10%, and WUV15%. However, baseline fatigue index score was significantly worse than all other scores (P ≤.001–.002, d = 1.35–2.46 [large]) following the loaded conditions. Conclusions: The findings demonstrated that a dynamic loaded warm-up increases an athlete’s initial RCOD performance up to the 8-minute postwarm-up intervention. Therefore, strength coaches need to consider using weighted vests during the warm-up for trained athletes in order to acutely optimize RCODs.

Fighting success in relation to body mass and drumming activity in the male wolf spider Hygrolycosa rubrofasciata

1997 ◽  
Vol 75 (9) ◽  
pp. 1532-1535 ◽  
Author(s):  
Janne Kotiaho ◽  
Rauno V. Alatalo ◽  
Johanna Mappes ◽  
Silja Parri
Keyword(s):  
Sexual Selection ◽  
Body Mass ◽  
Wolf Spider ◽  
Male Body ◽  
Male Courtship ◽  
Hygrolycosa Rubrofasciata ◽  
Males And Females ◽  
A Minor ◽  
Selection Of ◽  
Agonistic Encounters

In the wolf spider Hygrolycosa rubrofasciata, males court females by drumming dry leaves with their abdomen. Females prefer to mate with the most actively drumming males, and courtship drumming activity is also positively correlated with male viability. However, body mass of the males seems to have only a minor, if any, effect on female choice or male viability. There is also no correlation between male body mass and courtship drumming activity. We studied the effect of body mass and courtship drumming activity on the outcome of agonistic encounters between male H. rubrofasciata. For this purpose, males and females were randomly placed in a plastic arena, where male courtship drumming activity and agonistic encounters were recorded. Large differences in body mass and drumming activity between two rivals seemed to independently increase the probability of the larger or more active males winning. We conclude that while courtship drumming activity affects the fighting success of the males, and body mass more so, male–male interactions may not be of major importance in sexual selection of H. rubrofasciata.

scholarly journals The Effect of Hand Dimensions, Hand Shape and Some Anthropometric Characteristics on Handgrip Strength in Male Grip Athletes and Non-Athletes

2011 ◽  
Vol 29 (1) ◽  
pp. 151-159 ◽  
Author(s):  
Ali Fallahi ◽  
Ali Jadidian
Keyword(s):  
Body Mass ◽  
Linear Trend ◽  
Handgrip Strength ◽  
Pearson Correlation ◽  
Linear Regression Analysis ◽  
Body Height ◽  
Dominant Hand ◽  
Hand Shape ◽  
Significant Difference ◽  
Anthropometric Characteristics

The Effect of Hand Dimensions, Hand Shape and Some Anthropometric Characteristics on Handgrip Strength in Male Grip Athletes and Non-AthletesIt has been suggested that athletes with longer fingers and larger hand surfaces enjoy stronger grip power. Therefore, some researchers have examined a number of factors and anthropometric variables that explain this issue. To our knowledge, the data is scarce. Thus, the aim of this study was to investigate the effect of hand dimensions, hand shape and some anthropometric characteristics on handgrip strength in male grip athletes and non-athletes. 80 subjects aged between 19 and 29 participated in this study in two groups including: national and collegian grip athletes (n=40), and non-athletes (n=40). Body height and mass were measured to calculate body mass index. The shape of the dominant hand was drawn on a piece of paper with a thin marker so that finger spans, finger lengths, and perimeters of the hand could be measured. The hand shape was estimated as the ratio of the hand width to hand length. Handgrip strength was measured in the dominant and non-dominant hand using a standard dynamometer. Descriptive statistics were used for each variable and independent t test was used to analyze the differences between the two groups. The Pearson correlation coefficient test was used to evaluate the correlation between studied variables. Also, to predict important variables in handgrip strength, the linear trend was assessed using a linear regression analysis. There was a significant difference between the two groups in absolute handgrip strength (p<0.001) and handgrip/height ratio (p<0.001). The indices of body height, body mass, lean body mass and body fat content (p<0.001) were significantly greater in grip athletes. All hand variables except FS1-4 (p>0.05) were significantly different between the groups (p<0.001). After controlling body mass all hand anthropometric characteristics except thumb length (r=0.240, p=0.135), hand shape (r=-0.029, p=0.858), middle finger length (r=0.305, p=0.056) and forearm circumference (r=0.162, p=0.319) significantly correlated with handgrip strength in grip athletes, but not in non-athletes, except for forearm circumference (r=0.406, p=0.010). The results showed that handgrip strength and some of the hand dimensions may be different in athletes who have handgrip movements with an object or opponent in comparison to non-athletes. Also, there was a significant positive correlation between handgrip strength and most of the hand dimensions in grip athletes. Therefore, these can be used in talent identification in handgrip-related sports and in clinical settings as well.

scholarly journals Reaktivní agilita před a po sportovně-specifickém rozcvičení u hráčů stolního tenisu

2015 ◽  
Vol 9 (1) ◽  
pp. 38-44
Author(s):  
Pavel Vacenovský ◽  
Tomáš Vencúrik ◽  
Martin Sebera
Keyword(s):  
Body Weight ◽  
Repeated Measures ◽  
Body Height ◽  
Table Tennis ◽  
Warm Up ◽  
Significant Difference ◽  
Before And After ◽  
Reactive Agility ◽  
National League ◽  
The Difference

The aim of the study was to determine and compare the reactive agility league players and players of regional competitions and its changes due to sport-specific warm-up. The research sample consisted of 43 players, who were divided into two groups. First group consisted of 22 players from teams playing in the national league competitions (24.3 ± 5.6 years, body height 179.4 ± 8 cm, body weight 74.8 ± 10.4 kg), the second group of 21 players playing lower regional competitions (26.7 ± 5.64 years, body height 180.2 ± 7.7 cm, body weight 77.8 ± 10.5 kg). We used Fitro agility test modified for table tennis before and after warm-up. For data analysis was used two-way ANOVA with repeated measures. When comparing reactive agility, we found significant difference before and after the sport-specific warm-up for group of league players (885.94 ± 122.69 ms before the warm-up, 842.80 ± 119.48 ms after the warm-up, an improvement of 4.87 %, p <0.0004) and also for the group of players from lower competitions (932.96 ± 114.78ms before the warm-up, 871.90 ± 119.68 ms after the warm-up, an improvement of 6.54 %, p < 0.0002). Although league players achieved better results, the difference between the groups was found not significant. The nonsignificant statistic values for interaction indicates, that league players did not respond to the sport-specific warm-up differently than players from lower competitions. Sport-specific warm-up is important for improving the reactive agility and therefore should not be underestimated.

scholarly journals Incidence, severity and perceived susceptibility of COVID-19 in the UK CrossFit population

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Athalie Redwood-Brown ◽  
Grant William Ralston ◽  
Jennifer Wilson
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Online Survey ◽  
Body Height ◽  
Cross Sectional Study ◽  
Sample Population ◽  
Separate Analysis ◽  
Class Iii ◽  
Cross Sectional ◽  
Significant Difference

Abstract Background Contemporary literature indicates that a higher body mass index (BMI) serves as a risk factor for metabolic disease and is also correlated with greater disease severity. Subsequently, it has been linked to increased COVID-19 severity. The purpose of the study was to investigate whether regular CrossFit™ participation was associated with lower BMI, decreased COVID-19 severity and susceptibility. Methods A cross-sectional study was conducted on 1806 CrossFit™ (CF) participants. Participants were asked about their age (yrs), sex (male vs. female), ethnic group, body height (cm) and weight (kg). Body mass index (BMI, kg/m2) was computed and consistent with WHO (2018) criteria. Participants self-reported their training history, health and lifestyle history, nutritional customs, present training status and suspected levels of exposure to COVID-19. Once submitted the collected data were coded, cleaned and analysed. Results The final model comprised of 1806 CF individuals from an online survey response rate of 2086. The participants age ranged from 18 to 65+ yrs. Self-reported mean body mass index (BMI: kg/m2) reported that < 1% were underweight, 41% were healthy, 46% overweight, 10% class I obese, 2% class II obese, and < 1% class III obese. A Kruskal–Wallis H test compared gender and self-reported probability of being infected with COVID-19 with significant differences between subgroups (x2 (4, N = 1739) = 10.86, p = 0.03). Analysis of BMI and perceived severity of COVID-19 revealed a difference however not, significant (x2 (4, N = 1739) = 9.46, p = 0.051). Results on BMI and perceived probability of COVID-19 infection revealed no significant difference (x2 (4, N = 1739) = 2.68, p = 0.61). A separate analysis on BMI and perceived COVID-19 susceptibility revealed no significant difference (x2 (4, N = 1740) = 6.02, p = 0.20). Conclusions The purpose of the study was to establish whether habitual CrossFit™ participation is associated with reduced BMI, and to further investigate whether habitual participation impacted perceptions of disease. Results of the study indicate that self-reported CrossFit™ participation during the first UK lockdown, measured in minutes of exercise was indicative of a lower BMI. This has been associated with greater host immunity to disease. A history of CrossFit™ participation was not shown to impact perceptions of disease. However, our sample population reported few changes to habitual exercise during lockdown which may be due to the ‘community’ and increased adherence associated with CrossFit™.

scholarly journals Motor Learning of Complex Tasks with Augmented Feedback: Modality-Dependent Effectiveness

2021 ◽  
Vol 18 (23) ◽  
pp. 12495
Author(s):  
Jarosław Jaszczur-Nowicki ◽  
Oscar Romero-Ramos ◽  
Łukasz Rydzik ◽  
Tadeusz Ambroży ◽  
Michał Biegajło ◽  
...  
Keyword(s):  
Motor Learning ◽  
Body Mass ◽  
Visual Feedback ◽  
Vertical Jump ◽  
Body Height ◽  
Verbal Feedback ◽  
Complex Tasks ◽  
Significant Difference ◽  
Verbal Group ◽  
Post Test

Background: This paper aims to evaluate the effectiveness of feedback modalities in the motor learning of complex tasks. Methods: This study examined sixty-one male university students randomised to three groups: group Verbal (VER) = 20 (body height 178.6 ± 4.3 cm, body mass 81.3 ± 3.7 kg, age 20.3 ± 1.2 years), group Visual (VIS) = 21 (body height 179 ± 4.6 cm, body mass 82 ± 3.4 kg, age 20.3 ± 1.2 years), and group Verbal–Visual (VER&VIS) = 20 (body height 178.6 ± 4.3 cm, body mass 81.3 ± 3.7 kg, age 20.3 ± 1.2 years). The duration of the experiment was 6 months. Training sessions were performed three times per week (on Mondays, Wednesdays, and Fridays). The participants were instructed to perform a vertical jump with an arm swing (with forward and upward motion). During the jump, the participants pulled their knees up to their chests and grabbed their lower legs. The jump was completed with a half-squat landing, with arms positioned sideward. The jumping performance was rated by three gymnastic judges on a scale from 1 to 10. Results: A Tukey post hoc test revealed that in the post-test, a significant difference in the quality of performance was found between the Verbal group concerning errors combined with visual feedback on how to correct them (VER&VIS), the Verbal group concerning errors (VER), and the Visual group with visual feedback on the correctness of task performance (VIS). The ratings observed in the post-test were significantly higher in group VER&VIS than in groups VER and VIS (9%; p < 0.01 and 15%; p < 0.001, respectively). All judges’ ratings observed in group VER&VIS and VIS decreased insignificantly, but in group VER the ratings improved insignificantly. Conclusion: Providing verbal feedback combined with visual feedback on how to correct errors made in performing vertical jumps proved more effective than the provision of verbal feedback only or visual feedback only.

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