THE CONCURRENT VALIDITY OF A MOVING CAMERA APPARATUS IN 2-DIMENSIONAL MOTION ANALYSIS: A SWIMMING STUDY

Öz

This study describes the building of a moving camera apparatus for use in video-based motion analysis and reports its validity in the horizontal velocity of freestyle swimming. Nine male swimmers (height = 178.3 ± 6.3cm, weight = 82.6 ± 5.8 kg, age = 22.3 ± 3.86 years) participated to the study. Twenty meters freestyle swimming performances were recorded using both a moving camera apparatus and a stationary camera. A marker placed on the lumbar region of the swimmers was tracked to calculate horizontal velocity. After 2D motion analyses, the data obtained by two different methods were investigated. Horizontal velocities calculated using stationary camera recordings were taken as reference. Results showed that the horizontal velocities calculated using the moving camera apparatus’s recordings did not deviate from reference values more than 0.05 m/s at any point of the time series. Hoeffding’s D measure test revealed significant dependencies for 18 data couples (p<.05) indicating data series draw a similar trajectory. In conclusion, the accuracy of the apparatus allows for kinematic analyses in swimming and the can be used as an alternative to stationary cameras

Anahtar Kelimeler

• Swimming
• Video
• Motion Analysis,
• Kinematics

İKİ BOYUTLU HAREKET ANALİZİNDE HAREKETLİ KAMERA APARATININ UYUM GEÇERLİĞİ: BİR YÜZME ÇALIŞMASI

Öz

Bu çalışma, video tabanlı hareket analizlerinde kullanılmak üzere hareketli kamera aparatının yapımını açıklamakta ve serbest stil yüzmenin yatay hızı için sistemin geçerliğini rapor etmektedir. Çalışmaya dokuz erkek yüzücü (boy = 178.3 ± 6.3 cm, ağırlık = 82.6 ± 5.8 kg, yaş = 22.3 ± 3.86 yıl) katılmıştır. Yirmi metre serbest stil yüzme performansları hem hareketli kamera sistemi hem de sabit bir kamera kullanılarak kaydedilmiştir. Yüzücülerin bel bölgesine yerleştirilen bir işaretleyici yatay hızı hesaplamak amacıyla hareket analiz yazılımı kullanılarak takip edilmiştir. İki boyutlu hareket analizlerinin ardından iki sistemden elde edilen veriler incelenmiştir. Sabit kamera kayıtları kullanılarak hesaplanan yatay hızlar referans olarak kabul edilmiştir. Sonuçlar, hareketli kamera aparatı kullanılarak hesaplanan yatay hızların zaman serilerinin hiçbir noktasında referans değerlerden 0.05m/s’den fazla sapmadığını göstermiştir. Hoeffding’in D testi, 18 veri çiftinin anlamlı ölçüde birbirine bağımlı olduğunu (p<.05) ve veri serilerinin benzer eğriler çizdiğini ortaya koymuştur. Sonuç olarak geliştirilen aparatın hassasiyeti yüzmede kinematik analizlerin yapılmasına izin vermektedir ve sabit kamera sistemlerine alternatif olarak kullanılabilir.

Anahtar Kelimeler

• Yüzme
• Video
• Hareket Analizi
• Kinematik

Kaynakça

1. McGinnis PM. (2013). Biomechanics of sport and exercise. Human Kinetics. IL, 383-393.
2. Richards J. (2008). Biomechanics in clinic and research an interactive teaching and learning course. Elsevier. Edinburgh, 243-247.
3. Gonjo T., Olstad BH. (2021) Race analysis in competitive swimming: A narrative review. International Journal of Environmental Research and Public Health. 18(1), 69-75.
4. Craig AB., Pendergast DR. (1979). Relationships of stroke rate, distance per stroke, and velocity in competitive swimming. Medicine and Science in Sports. 11(3), 278-283.
5. Mooney R., Corley G., Godfrey A., Osborough C., Quinlan L., ÓLaighin G. (2015). Application of video-based methods for competitive swimming analysis: A systematic review. Sports and Exercise Medicine. 1(5), 133-150.
6. El-Sallam AA., Bennamoun M., Honda K., Lyttle A., Alderson, J. (2015). Towards a fully automatic markerless motion analysis system for the estimation of body joint kinematics with application to sport analysis. Paper presented at the GRAPP. Berlin. Almanya, 58-69.
7. Magalhaes FA., Sawacha Z., Di Michele R., Cortesi M., Gatta G., Fantozzi S. (2013). Effectiveness of an automatic tracking software in underwater motion analysis. Journal of Sports Science & Medicine. 12(4), 660-667.
8. Chiari L., Della Croce U., Leardini A., Cappozzo A. (2005). Human movement analysis using stereophotogrammetry: Part 2: Instrumental errors. Gait & Posture. 21(2), 197-211.

9. Strzała M., Krężałek P., Kaca M., Głąb G., Ostrowski A., Stanula A., Tyka A. (2012). Swimming speed of the breaststroke kick. Journal of Human Kinetics. 35(1), 133-139.
10. Mason B., Mackintosh C., Pease D. (2012). The development of an analysis system to assist in the correction of inefficiencies in starts and turns for elite competitive swimming. Paper presented at the ISBS-Conference Proceedings Archive. Melbourne. Australia, 249-252.
11. Michaela B., Jaroslav M., Jan Š., Hana L. (2016). Biomechanical analysis of front crawl arm stroke and leg kick by tachograph measuring system. Ovidius University Annals, Series Physical Education & Sport Science, Movement & Health. 16, 293-300.
12. Sidney M., Paillette S., Hespel J., Chollet D., Pelayo P. (2001). Effect of swim paddles on the intra-cyclic velocity variations and on the arm coordination of front crawl stroke. Paper presented at the ISBS-Conference Proceedings Archive. Sanfransico. USA, 39-42.
13. Feitosa WG., Costa MJ., Morais JE., Garrido ND., Silva AJ., Lima AB., Barbosa TM. (2013). A mechanical speedo-meter to assess swimmer’s horizontal intra-cyclic velocity: validation for breaststroke and butterfly stroke. Paper presented at the ISBS-Conference Proceedings Archive. Taipei. Taiwan, 12-16.
14. Leblanc H., Seifert L., Tourny-Chollet C., Chollet D. (2007). Intra-cyclic distance per stroke phase, velocity fluctuations and acceleration time ratio of a breaststroker's hip: A comparison between elite and nonelite swimmers at different race paces. International Journal of Sports Medicine. 28(2), 140-147.
15. Puel F., Seifert L., Hellard P. (2014). Validation of an inertial measurement unit for the determination of the longitudinal speed of a swimmer. Paper presented at the Proceedings of the XIIth International Symposium for Biomechanics and Medicine in Swimming. Canberra. Australia, 484-489.
16. Morouço P., Keskinen KL., Vilas-Boas JP., Fernandes RJ. (2011). Relationship between tethered forces and the four swimming techniques performance. Journal of Applied Biomechanics. 27(2), 161-169.
17. Dadashi F., Millet G., Aminian K. (2013). Inertial measurement unit and biomechanical analysis of swimming: An update. Schweizerische Zeitschrift für Sportmedizin und Sporttraumatologie. 61(3), 28-33.
18. Lafontaine D., Lamontagne M. (2003). 3-D kinematics using moving cameras. Part 1: Development and validation of the mobile data acquisition system. Journal of Applied Biomechanics. 19(4), 372-377.
19. Santos S., Takahashi DY., Nakata A., Fujita A. (2014). A comparative study of statistical methods used to identify dependencies between gene expression signals. Briefings in Bioinformatics. 15(6), 906-918.
20. Holden-Douilly L., Pourcelot P., Chateau H., Falala S., Crevier-Denoix N. (2013). A method to minimise error in 2D-DLT reconstruction of non-planar markers filmed with a moving camera. Computer Methods in Biomechanics and Biomedical Engineering. 16(9), 929-36.
21. Bernardina GR., Monnet T., Cerveri P., Silvatti AP. (2019). Moving system with action sport cameras: 3D kinematics of the walking and running in a large volume. PloS One. 14(11), e0224182.