Dartfish Research Articles

Effect of meditative thinking on kinematic aspects of the tennis serve

The purpose of this study was to measure how much rookie players were thinking meditatively while mastering the serve technique, identifying the values of kinetic transmission and streamline for their performance of this skill as well as the connection, contribution, and influence of meditative thought on kinetic transmission and streamline when they perform the serve skill in tennis. This study employed a descriptive correlational design on a sample of 15 young tennis players who were specifically chosen to represent the entire target group. These players were selected from the Tennis Academy in Baghdad for the sport season 2018-2019. The Eysenck & Wilson Reflectiveness Scale was used after its translation into Arabic language. Each player’s performance for serve skill was used to measure the transmission of momentum between body parts and the kinetic streamline using the Dart fish–Team Pro 5 full version. Data were analyzed using the statistical package for social science (SPSS) for windows, version 25. The study results revealed that young players who have a high level of meditative thinking can control and master transmission of momentum between body parts with a streamline that reflects an improved performance for the serve skill in tennis. It is necessary to pay attention to support the meditative thinking in the teaching sessions for the young beginners in tennis and employing the kinetic activities to achieve the required model in performance. Furthermore, it is necessary to support the coaches in how to measure the meditative thinking and its improving to go parallel to improve the skillful performance in tennis to make players realize the local and international professionalism.

The relation between posture and fighting style: case of kung fu wushu (sanda)

The aim of this study is to analyze the relationship between initial posture (pre-contact posture) and combat style (boxing, foot and fight); thus, to establish a specific modeling. The descriptive analytical method of the video recordings of the combats organized with our sample (n=6) (2 of each combat style) was used to obtain the initial kinogram via the Dart Fish software. Inter-style postural similarities and extra-style postural differences were found, which helped us to put in place specific postural indices. Knowing the opponent's fighting style may betray some of his combat strategy, but can we hide these postural clues? Or more, can we give false clues (a lure) to deceive the opponent, which will make combat a rather mental challenge.

Performance Analysis of Men's 110-m Hurdles using Rhythmic Units

Objective: This study aimed to create a strategic training method to enhance optimal athletic ability using information from 1H to 10H rhythmic units. Method: Top three world class athletes and three national winners of 110-m hurdle finals from the 2010 Daegu International Athletics Competition and 2017 National Athletics Championship, respectively, were selected. To analyze the kinematic variables, Dartfish 9.0 was used for two-dimensional analysis. Results: Regarding the interval time from the start to the finish line, the national athletes took less time during the pure acceleration phase (start to 1H) than the foreign athletes. The horizontal velocity increase was slower after 1H; the national athletes showed a lack of ability to accelerate at the interval phases. Moreover, the hurdle clearance time between phases was longer in the national athletes than in the foreign athletes and lacked consistency. Conclusion: The national athletes lacked the ability to accelerate at the transition, maximum rhythm, rhythm maintenance, and re-acceleration phases and showed a longer hurdle clearance time. If technical improvements and strategic training methods using rhythmic units are applied for hurdling motions, the national athlete''s hurdling abilities, performance, and consistency could improve.

Wrist-Lagging Angle Impact on Both Golf Swing Distance and Accuracy

The purpose of this study was to investigate the impact of wrist-lagging angle on both distance and accuracy in golf downswing among NCAA Division I female golfers. Seven female golfers from a university of the East Coast of the United States volunteered to participate in the study. While performing a full swing with 7-iron, a standardized Golf Simulator was used to obtain swing related data and Dartfish was utilized to measure the wrist angles in the downswing. Multivariate General Linear Regression (MGLR) analysis was conducted to determine predictor variables for hitting distance and accuracy. The results have shown that for irons wrist-lagging angle is a significant predictor for the accuracy, but not for the distance. Other variables such as club head speed, smash effect, sidespin and backspin were also found significant in MGLR model (p < .01). Future studies should gain a comprehensive understand of how wrist-lagging angle impact on male golfers.

Age- and Sex-Related Walking Patterns in Unrestricted Inner City Park Trail Walkers

The present study examined age- and sex-related differences in the walking patterns of recreational park walkers during unrestricted walking. Three video cameras were unnoticeably and sequentially positioned along a paved park trail. Each camera continuously filmed free walkers who consecutively passed three segments of trail: down slope (DS; 5.83o, 83.5 m long), level (LV; 0o, 10 m long), and up slope (US; 8.90o, 98.4 m long, 2.23 m width), for one hour. Cameras recorded a 9-m distance of each representative segment, which was marked by plastic tape 2 cm wide. The visual image was stored on a digital video cassette, and a video digital program (Dart Fish) was utilized for analyzing step length (SL) and walking speed (WS). Only adults and clear images were included for analysis. The sex was identified and the age span was categorized visually into three groups (20 ? 39 years, young; 40 ? 59 years, middle; and ≥ 60 years, old age) by a technician. All recordings were conducted on a clear spring day. A total of 56 men and 121 women passed through all the trail segments analyzed. For men, the average SL was 81.3 ± 9.6, 82.3 ± 7.6, and 80.2 ± 8.8 cm, and the average WS was 1.42 ± 0.20, 1.40 ± 0.18, and 1.29 ± 0.19 m/sec on the DS, LV, and US trail segments, respectively, and was not different between age groups and the segments. For women, both SL (70.2 ± 5.2, 71.7 ± 3.7, and 68.6 ± 8.7 cm) and WS (1.23 ± 0.07, 1.22 ± 0.11, and 1.07 ± 0.18 m/s on the DS, LV, and US trail segments) of the old age group were significantly less than those of the other two age groups as well as that of aged men in corresponding trail segments (p < 0.05). No differences were observed in WS on all the trail segments between men and women. Based on the results, walking patterns of older women were distinctive compared to the youngers and the older men indicating age- and sexrelated differences of free walking in terrestrial environment.

Parioglossus galzini, a new species of ptereleotrid dartfish from Rapa Island (Teleostei: Gobioidei: Ptereleotridae)

A new species of dart fish, Parioglossus galzini sp. nov., is described based on specimens collected in Haurei Bay, Rapa Island (French Polynesia). It is distinguished from all other described species of Parioglossus as follows: dark lateral body stripe absent, 100 or more scales in longitudinal series from above pectoral-fin base to base of caudal fin, pectoral-fin rays 19 21, membrane of first dorsal fin attached to second dorsal fin in males and females, mature males with dorsal-fin spines 3 5 filamentous and about equal in length, fresh males with narrow yellow stripe running dorsolaterally along body from head to caudal fin.