Spatial-temporal variables for swimming coaches: A comparison study between video and TritonWear sensor

2021 ◽  
pp. 174795412110137
Author(s):  
Robin Pla ◽  
Thibaut Ledanois ◽  
Escobar David Simbana ◽  
Anaël Aubry ◽  
Benjamin Tranchard ◽  
...  
Keyword(s):  
Swimming Performance ◽  
Video Recording ◽  
Open Water ◽  
Percentage Error ◽  
Stroke Index ◽  
Wearable Sensor ◽  
Stroke Length ◽  
Video Recordings ◽  
Temporal Variables ◽  
Training Sets

The main aim of this study was to evaluate the validity and the reliability of a swimming sensor to assess swimming performance and spatial-temporal variables. Six international male open-water swimmers completed a protocol which consisted of two training sets: a 6×100m individual medley and a continuous 800 m set in freestyle. Swimmers were equipped with a wearable sensor, the TritonWear to collect automatically spatial-temporal variables: speed, lap time, stroke count (SC), stroke length (SL), stroke rate (SR), and stroke index (SI). Video recordings were added as a “gold-standard” and used to assess the validity and the reliability of the TritonWear sensor. The results show that the sensor provides accurate results in comparison with video recording measurements. A very high accuracy was observed for lap time with a mean absolute percentage error (MAPE) under 5% for each stroke (2.2, 3.2, 3.4, 4.1% for butterfly, backstroke, breaststroke and freestyle respectively) but high error ranges indicate a dependence on swimming technique. Stroke count accuracy was higher for symmetric strokes than for alternate strokes (MAPE: 0, 2.4, 7.1 & 4.9% for butterfly, breaststroke, backstroke & freestyle respectively). The other variables (SL, SR & SI) derived from the SC and the lap time also show good accuracy in all strokes. The wearable sensor provides an accurate real time feedback of spatial-temporal variables in six international open-water swimmers during classical training sets (at low to moderate intensities), which could be a useful tool for coaches, allowing them to monitor training load with no effort.

scholarly journals Modeling the Links Between Young Swimmers’ Performance: Energetic and Biomechanic Profiles

2010 ◽  
Vol 22 (3) ◽  
pp. 379-391 ◽  
Author(s):  
Tiago M. Barbosa ◽  
Mário Costa ◽  
Daniel A. Marinho ◽  
Joel Coelho ◽  
Marc Moreira ◽  
...  
Keyword(s):  
Structural Equation ◽  
Swimming Performance ◽  
Flow Analysis ◽  
Equation Modeling ◽  
Swimming Velocity ◽  
Stroke Index ◽  
Analysis Model ◽  
Stroke Length ◽  
Propulsive Efficiency ◽  
Biomechanical Assessment

The aim was to develop a path-flow analysis model for young swimmers’ performance based on biomechanical and energetic parameters, using structural equation modeling. Thirty-eight male young swimmers served as subjects. Performance was assessed by the 200-m freestyle event. For biomechanical assessment the stroke length, the stroke frequency and the swimming velocity were analyzed. Energetics assessment included the critical velocity, the stroke index and the propulsive efficiency. The confirmatory model explained 79% of swimming performance after deleting the stroke index-performance path, which was nonsignificant (SRMR = 0.06). As a conclusion, the model is appropriate to explain performance in young swimmers.

scholarly journals Energetic and Biomechanical Contributions for Longitudinal Performance in Master Swimmers

2020 ◽  
Vol 5 (2) ◽  
pp. 37
Author(s):  
Daniel A. Marinho ◽  
Maria I. Ferreira ◽  
Tiago M. Barbosa ◽  
José Vilaça-Alves ◽  
Mário J. Costa ◽  
...  
Keyword(s):  
Blood Lactate ◽  
Swimming Performance ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Stroke Index ◽  
Front Crawl ◽  
Stroke Length ◽  
Propelling Efficiency ◽  
Peak Blood ◽  
Peak Blood Lactate

Background: The current study aimed to verify the changes in performance, physiological and biomechanical variables throughout a season in master swimmers. Methods: Twenty-three master swimmers (34.9 ± 7.4 years) were assessed three times during a season (December: M1, March: M2, June: M3), in indoor 25 m swimming pools. An incremental 5 × 200 m test was used to evaluate the speed at 4 mmol·L−1 of blood lactate concentration (sLT), maximal oxygen uptake (VO2max), peak blood lactate ([La-]peak) after the test, stroke frequency (SF), stroke length (SL), stroke index (SI) and propelling efficiency (ηp). The performance was assessed in the 200 m front crawl during competition. Results: Swimming performance improved between M1, M2 (2%, p = 0.03), and M3 (4%, p < 0.001). Both sLT and VO2max increased throughout the season (4% and 18%, p < 0.001, respectively) but not [La-]peak. While SF decreased 5%, SL, SI and ηp increased 5%, 7%, and 6% (p < 0.001) from M1 to M3. Conclusions: Master swimmers improved significantly in their 200 m front crawl performance over a season, with decreased SF, and increased SL, ηp and SI. Despite the improvement in energetic variables, the change in performance seemed to be more dependent on technical than energetic factors.

Analysis of Swimming Performance from Physical, Physiological, and Biomechanical Parameters in Young Swimmers

2007 ◽  
Vol 19 (1) ◽  
pp. 70-81 ◽  
Author(s):  
Jaak Jürimäe ◽  
Kaja Haljaste ◽  
Antonio Cicchella ◽  
Evelin Lätt ◽  
Priit Purge ◽  
...  
Keyword(s):  
Energy Cost ◽  
Swimming Performance ◽  
Peak Oxygen Consumption ◽  
Stroke Index ◽  
Front Crawl ◽  
Stroke Length ◽  
Technical Parameters ◽  
Arm Span ◽  
Biomechanical Parameters ◽  
Energy Cost Of Swimming

The purpose of this study was to examine the influence of the energy cost of swimming, body composition, and technical parameters on swimming performance in young swimmers. Twenty-nine swimmers, 15 prepubertal (11.9 ± 0.3 years; Tanner Stages 1−2) and 14 pubertal (14.3 ± 1.4 years; Tanner Stages 3−4) boys participated in the study. The energy cost of swimming (Cs) and stroking parameters were assessed over maximal 400-m front-crawl swimming in a 25m swimming pool. The backward extrapolation technique was used to evaluate peak oxygen consumption (VO2peak). A stroke index (SI; m2 · s−1 · cycles−1) was calculated by multiplying the swimming speed by the stroke length. VO2peak results were compared with VO2peak test in the laboratory (bicycle, 2.86 ± 0.74 L/min, vs. in water, 2.53 ± 0.50 L/min; R2 = .713; p = .0001). Stepwise-regression analyses revealed that SI (R2 = .898), in-water VO2peak (R2 = .358), and arm span (R2 = .454) were the best predictors of swimming performance. The backward-extrapolation method could be used to assess VO2peak in young swimmers. SI, arm span, and VO2peak appear to be the major determinants of front-crawl swimming performance in young swimmers.

Case Study: Comparison of Swimsuits and Wetsuits Through Biomechanics and Energetics in Elite Female Open Water Swimmers

2021 ◽  
pp. 1-7
Author(s):  
Rodrigo Zacca ◽  
Bruno Mezêncio ◽  
Flávio A. de Souza Castro ◽  
Fábio Y. Nakamura ◽  
David B. Pyne ◽  
...  
Keyword(s):  
Swimming Performance ◽  
Open Water ◽  
Peak Oxygen Uptake ◽  
Mean Difference ◽  
Stroke Rate ◽  
Stroke Length ◽  
World Series ◽  
Shoulder Flexion ◽  
Drag Factor

Aim: The authors investigated how the Arena Powerskin R-EVO Closed Back swimsuit and Arena Carbon Triwetsuit (full-sleeve wetsuit), both approved by the Fédération Internationale de Natation (FINA) regulations, affect biomechanics and energetics of 3 elite female open water (OW) swimmers at maximal and 4 submaximal swimming intensities. Methods: Three elite female OW swimmers (OW1 = 24 y, 1.64 m, 60 kg; OW2 = 23 y, 1.69 m, 65 kg; OW3 = 27 y, 1.63 m, 64.5 kg) were tested 1 week prior to a FINA/CNSG (China National Sports Group) Marathon Swim World Series event and 40 days before the 18th FINA World Championships 2019. Each OW swimmer completed 2 identical testing sessions, one with a swimsuit and other with a wetsuit, involving shoulder flexion power output assessed from medicine-ball throw, maximal performance and drag coefficient assessment, and an incremental intermittent swim test at 4 different relative intensities. Results: Estimated peak oxygen uptake was 4.4 L·min−1 for OW1, 5.6 L·min−1 for OW2, and 5.0 L·min−1 for OW3. Despite a distinct behavior observed on index of coordination for OW3, a null index of synchronization, increased stroke rate (mean difference = 2%–8%), reduced drag factor (minimum = −14%; maximum = −30%), lower energy cost (mean difference = −2% to −6%), and faster performance (mean difference = 2% to 3%) were observed with the wetsuit compared with swimsuit for all elite OW swimmers. Conclusion: The wetsuit enhances submaximal swimming performance, and this increase is dependent on the OW swimmer’s characteristics. The higher stroke rate and lower stroke length detected with wetsuit could be related to movement constraints imposed by the suit.

scholarly journals Young Swimmers’ Middle-Distance Performance Variation within a Training Season

2021 ◽  
Vol 18 (3) ◽  
pp. 1010
Author(s):  
Sara Ferreira ◽  
Diogo Duarte Carvalho ◽  
Ricardo Cardoso ◽  
Manoel Rios ◽  
Susana Soares ◽  
...  
Keyword(s):  
Performance Improvement ◽  
Swimming Performance ◽  
Stroke Index ◽  
Age Group ◽  
Swimming Training ◽  
Front Crawl ◽  
Stroke Length ◽  
Post Exercise ◽  
Performance Variation ◽  
Technical Proficiency

The current study aimed to longitudinally evaluate anthropometric, physiological, and biomechanical variables related to middle-distance performance during a 45-week swimming training season. Thirty-four swimmers (age: 12.07 ± 1.14 years) performed a maximum of 400 m front crawl at the beginning (T1) and finish of the first macrocycle (T2, 15 weeks) and the finish of the second (T3, 18 weeks) and third macrocycles (T4, 12 weeks). Time-related variables, stroke rate (SR), stroke length (SL), and stroke index (SI) were recorded during the test, and blood lactate ([La]) and glucose ([Glu]) concentrations were measured post-exercise. The time of the 400 m effort decreased after each macrocycle (T2 vs. T1, 7.8 ± 5.6%; T3 vs. T2, 3.7 ± 3.1%; T4 vs. T3, 3.8 ± 3.4%; p < 0.01). Four hundred meter speed changes between T1 and T2 were positively related to variations in [La], [Glu], SL, and SI (r = 0.36–0.60, p < 0.05). Changes between T2 and T3 were related to SI only (r = 0.5, p < 0.05), and modifications between T3 and T4 were associated with SL and SI variations (r = 0.34 and 0.65, p < 0.05). These results indicate that a well-structured year plan including three macrocycles leads to a significant age-group swimming performance improvement, mostly connected with an increase in technical proficiency.

Effects of Time and Perceptual Orientation on Actors' and Observers' Attributions

1984 ◽  
Vol 58 (1) ◽  
pp. 23-30
Author(s):  
Donald S. Martin ◽  
Ming-Shiunn Huang
Keyword(s):  
Video Recording ◽  
Control Group ◽  
Control Groups ◽  
Video Recordings ◽  
Before And After ◽  
Perceptual Orientation ◽  
Initial Difference ◽  
Variety Show ◽  
And Control ◽  
Unrelated Variety

The actor/observer effect was examined by Storms in a 1973 study which manipulated perceptual orientation using video recordings. Storms' study was complex and some of his results equivocal. The present study attempted to recreate the perceptual reorientation effect using a simplified experimental design and an initial difference between actors and observers which was the reverse of the original effect. Female undergraduates performed a motor co-ordination task as actors while watched by observers. Each person made attributions for the actor's behaviour before and after watching a video recording of the performance. For a control group the video recording was of an unrelated variety show excerpt. Actors' initial attributions were less situational than observers'. Both actors and observers became more situational after the video replay but this effect occurred in both experimental and control groups. It was suggested the passage of time between first and second recording of attributions could account for the findings and care should be taken when interpreting Storms' (1973) study and others which did not adequately control for temporal effects.

QUALITATIVE CHANGES IN RHYTHMIC GYMNASTICS HOOP THROWS FROM THE PERSPECTIVE OF BIOMECHANICAL ANALYSIS

2020 ◽  
pp. 1-8
Author(s):  
Raluca Tanasa
Keyword(s):  
Correlation Coefficient ◽  
Video Recording ◽  
Biomechanical Analysis ◽  
Fundamental Groups ◽  
Horizontal Distance ◽  
Video Recordings ◽  
Rhythmic Gymnastics ◽  
Female Gymnasts ◽  
Execution Technique ◽  
Qualitative Changes

Throws and catches in rhythmic gymnastics represent one of the fundamental groups of apparatus actuation. They represent for the hoop actions of great showmanship, but also elements of risk. The purpose of this paper is to improve the throw execution technique through biomechanical analysis in order to increase the performance of female gymnasts in competitions. The subjects of this study were 8 gymnasts aged 9-10 years old, practiced performance Rhythmic Gymnastics. The experiment consisted in video recording and the biomechanical analysis of the element “Hoop throw, step jump and catch”. After processing the video recordings using the Simi Motion software, we have calculated and obtained values concerning: launch height, horizontal distance and throwing angle between the arm and the horizontal. Pursuant to the data obtained, we have designed a series of means to improve the execution technique for the elements comprised within the research and we have implemented them in the training process. Regarding the interpretation of the results, it may be highlighted as follows: height and horizontal distance in this element have values of the correlation coefficient of 0.438 and 0.323, thus a mean significance of 0.005. The values of the arm/horizontal angle have improved for all the gymnasts, the correlation coefficient being 0.931, with a significance of 0.01. As a general conclusion, after the results obtained, it may be stated that the means introduced in the experiment have proven their efficacy, which has led to the optimisation of the execution technique, thus confirming the research hypothesis.

scholarly journals FaceSync: Open source framework for recording facial expressions with head-mounted cameras

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 702 ◽  
Author(s):  
Jin Hyun Cheong ◽  
Sawyer Brooks ◽  
Luke J. Chang
Keyword(s):  
Facial Expression ◽  
Open Source ◽  
Facial Expressions ◽  
Video Recording ◽  
Machine Learning Algorithms ◽  
Expression Data ◽  
Video Recordings ◽  
Automated Method ◽  
Open Source Framework ◽  
The Cost

Advances in computer vision and machine learning algorithms have enabled researchers to extract facial expression data from face video recordings with greater ease and speed than standard manual coding methods, which has led to a dramatic increase in the pace of facial expression research. However, there are many limitations in recording facial expressions in laboratory settings.  Conventional video recording setups using webcams, tripod-mounted cameras, or pan-tilt-zoom cameras require making compromises between cost, reliability, and flexibility. As an alternative, we propose the use of a mobile head-mounted camera that can be easily constructed from our open-source instructions and blueprints at a fraction of the cost of conventional setups. The head-mounted camera framework is supported by the open source Python toolbox FaceSync, which provides an automated method for synchronizing videos. We provide four proof-of-concept studies demonstrating the benefits of this recording system in reliably measuring and analyzing facial expressions in diverse experimental setups, including group interaction experiments.

scholarly journals Video Recording Made Easy: Applications for Gateway Library's One Button Studion

2014 ◽  
Vol 6 ◽  
Author(s):  
Jason Byrd ◽  
Todd Stafford ◽  
Royce Gildersleeve ◽  
Christal Ferrance ◽  
Kara Kiblinger
Keyword(s):  
Media Literacy ◽  
Video Recording ◽  
Video Recordings ◽  
Course Objectives ◽  
Amount Of Knowledge

Learn how easy video recording can be with the new OneButton Studio, located in Gateway Library. Presenters will share how this studio drastically reduces the amount of knowledge necessary to make professional video recordings and discuss applications in courses, including flipping the classroom, adding media literacy components to course objectives, and incorporating video recordings into assignments.

Deterrence of Piracy Employing IR Transmitter and Steganography System

2021 ◽  
Vol 1 (2) ◽  
pp. 32-40
Author(s):  
A.M. Prasanna Kumar ◽  
Bharathi Gururaj
Keyword(s):  
Mobile Phone ◽  
Film Industry ◽  
Video Recording ◽  
Research Work ◽  
Infrared Light ◽  
Novel Technique ◽  
Video Recordings ◽  
Light Rays ◽  
Film Piracy ◽  
Mobile Phone Camera

Moving picture entertainment is a foremost source of amusement for populace in today’s existence. To entertain populace a lot of investment is put into film production by the film makers. Their endeavour is being ruined by few people by pirate the movies substance. They do it by capture the video recording in mobile phone camera and upload it to websites or put up for sale it to people which cause huge loss. In this research work we are proposea novel technique for reduction of film piracy by avoiding fake video recordings of video in theatres. An indistinguishable luminosity is projected from the display to the whole spectators that falls on the camera lens which is sensitive to infrared light rays Makes the recorded video unfit to watch. A method is developed for anti-piracy system for film industry using steganography technique in MATLAB.

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