Deporte con dispositivos de posicionamiento global (GPS)aplicaciones y limitaciones

  1. Castellano, Julen 1
  2. Casamichana, David
  1. 1 Universidad del País Vasco/Euskal Herriko Unibertsitatea
    info

    Universidad del País Vasco/Euskal Herriko Unibertsitatea

    Lejona, España

    ROR https://ror.org/000xsnr85

Revista:
Revista de psicología del deporte

ISSN: 1132-239X 1988-5636

Año de publicación: 2014

Volumen: 23

Número: 2

Páginas: 355-364

Tipo: Artículo

Otras publicaciones en: Revista de psicología del deporte

Resumen

En el presente documento se hace una revisión no exhaustiva sobre la aplicabilidad y limitaciones de los dispositivos GPS en el ámbito deportivo. En el trabajo se detallan aspectos claves que técnicos e investigadores deberían considerar para valorar los límites de su aplicabilidad al tiempo que maximizar su uso. Las temáticas que se abordan pueden concretarse es los siguientes: funcionamiento, limitaciones, diferentes usos motivados por la variedad en la tipología de variables que registra, oportunidades de sincronización con el vídeo o con la representación 2D del movimiento de los jugadores en el espacio (para posteriores análisis más pormenorizados), así como la disponibilidad de la información en ‘tiempo real’. Además, la tecnología GPS está dando sus primeros pasos para aportar información no solo de las demandas físicas o energéticas de los deportistas, sino también de las conductas colectivas que jugadores y equipos despliegan en sus actividades (partido, juegos reducidos, etc). Valoradas las limitaciones y valoradas sus aplicaciones los usuarios podrán beneficiarse de los dispositivos GPS cuando se apliquen al análisis del rendimiento en la competición y el entrenamiento. Esta tecnología puede ayudar a entrenadores y atletas en el desarrollo de sus trabajos o actividades con precisión, inmediatez y riqueza informacional.

Referencias bibliográficas

  • Abad, P. (2005). Reducci ón del número de condición. Y deficiencia de rango en los sistemas de ecuaciones asociados a las observaciones de saté lites. Tesis Doctoral: Universidad de las Palmas de Gran Canaria.
  • Aughey, R. (2010). Australian football player work rate: evidence of fatigue and pacing? International Journal of Sports Physiology and Performance, 5(3), 394-405.
  • Aughey, R. (2011). Applications of GPS technologies to field sports. International Journal of Sports Physiology and Performance, 6(3), 295-310.
  • Aughey, R. Y Fallon, C. (2010). Real-time versus post-game GPS data in team sports. Journal of Science and Medicine in Sport, 13(3), 348-349.
  • Barbero-Á lvarez, J. C., Barbero-Álvarez, V., Gómez, M. Y Castagna, C. (2009). Análisis cinemá tico del perfil de actividad en jugadoras infantiles de fútbol mediante tecnología GPS. Kronos: la revista científica de actividad física. Y deporte,VIII( 14), 35-42.
  • Barbero-Á lvarez, J. C., Barbero-Álvarez, V.,. Y Granda, J. (2007). Perfil de actividad durante el juego en futbolistas infantiles. Apunts: Educación fí sica. Y deportes, 90, 33-41.
  • Barbero-Á lvarez, J. C., Barbero-Álvarez, V., Granda, J. Y Gómez, M. (2009). Demandas físicas. Y fisiológicas del fútbol 7 en categorí as inferiores. Kronos: la revista científica de actividad física. Y deporte, VIII(14), 43-48.
  • Barbero-Á lvarez, J. C. Y Castagna, C. (2007). Activity patterns in professional futsal players using global position tracking system. Journal of Sports Science and Medicine, 6(Supl. 10), 208-209.
  • Barbero-Á lvarez, J. C., Coutts, A., Granda, J., Barbero-Álvarez, V. Y Castagna, C. (2010). The validity and reliability of a global positioning satellite system device to assess speed and repeated sprint ability (RSA) in athletes. Journal of Science and Medicine in Sport, 13(2), 232-235.
  • Barbero-Á lvarez, J. C., Gómez, M., Barbero-Álvarez, V., Granda, J. Y Castagna, C. (2008). Heart rate and activity profile for young female soccer players. Journal of Human Sport and Exercise, 3(2), 1-11.
  • Barbero-Á lvarez, J. C., Soto, V. M. Y Granda, J. (2005). Diseno, desarrollo. Y validación de un sistema fotogramétrico para la valoración cinemátic a de la competición en deportes de equipo. Motricidad-European Journal of Human Movement, 13, 145-160.
  • Barros, R. M. L, Misuta, M. S., Menezes, R. P., Figueroa, P. J., Moura, F. A., Cunha, S. A., ..Leite , N. J. (2007). Analysis of the distances covered by first division Brazilian soccer players obtained with an automatic tracking method. Journal of Sports in Science and Medicine, 6(2), 233-242.
  • Bloomfield, J. , Polman, R. Y O'Donoghue, P. (2007). Reliability of the Bloomfield Movement Classification. International Journal of Performance Analysis of Sport, 7(1), 20-27.
  • Brewer, C., Dawson, B., Heasman, J., Stewart, G. Y Cormack, S. (2010). Movement pattern comparisons in elite (AFL) and sub-elite (WAFL) Australian football games using GPS. Journal of Science and Medicine in Sport, 13(6), 618-623.
  • Bucheit, M., Horo beanu, C., Mé ndez-Villanueva, A., Simpson, B. M. Y Bourdon, P. C. (2011). Effects of age and spa treatment on match running performance over two consecutive games in highly trained young soccer players. Journal of Sports Sciences, 2 9(6), 591-598.
  • Buchheit, M., Mé ndez-Villanueva, A., Simpson, B. M. Y Bourdoun, P.C. (2010a). Match running performance and fitness in youth soccer. International Journal of Sports Medicine, 31(11), 818-825.
  • Buchheit, M., Mendez-Villanueva, A., Simpson, B. M. Y Bourdon, P. C. (2010b). Repeated-sprint sequences during youth soccer matches. International Journal of Sports Medicine, 31(10), 709-716.
  • Carling, C., Bloomfield, J., Nelsen, L. Y Reilly, T. (2008). The role of motion analysis in elite soccer: contemporary performance measurement techniques and work rate data. Sports Medicine, 38(10), 839-862.
  • Casamichana, D. (2011). La tecnología GPS aplicada a la evaluación del entrenamiento. Y la competición en fútbol. Tesis Doctoral: Universidad del Paí s Vasco (UPV/EHU).
  • Casamichana, D. Y Castellano, J. (2011a). Demandas físicas en jugadores semiprofesionales de fútbol: se entrena igual que se compite? Cultura, Ciencia. Y Deporte, 6(17), 121-127.
  • Casamichana, D. Y Castellano, J. (2011b). Validez. Y fiabilidad de dispositivos GPS de 5 Hz en carreras cortas con cambio de dirección. Retos. Nuevas Tendencias en Educación Fí sica, Deporte. Y Recreación 9 19 30-33.
  • Casamichana, D., Castellano, J., Calleja-González, J. Y San Romá n, J. (2011). The use of accelometers to quantify the training load in soccer. Poster presented at the 7thWorld Congress on Science & football, Mayo 26-3 0, Nagoya (Japan).
  • Casamichana, D., Castellano, J., Calleja-González, J., San Romá n, J. Y Castagna, C. (2012). Relationship between indicators of training load in soccer players. Journal of Strength and Conditioning Research. Doi: 10.1519/JSC.0b013e3182548af1.
  • Casamichana, D., San Romá n-Quintana, J., Castellano, J. Y Calleja-González, J. (2012). Demandas físicas. Y fisiológicas en jugadores absolutos no profesionales durante partid os de fútbol 7: un estudio de caso. Cultura, Ciencia. Y Deporte, 7(29), 115-123.
  • Castagna, C., Impellizzeri, F., Cecchini, E., Rampinini, E. Y Barbero-Álvarez J. C. (2009). Effects of intermittent-endurance fitne ss on match performance in young male soccer players. Journal of Strength and Conditioning Research, 23(7), 1954-1959.
  • Castagna, C., Manzi, V., Impellizzeri, F., Weston, M. Y Barbero-Álvarez J. C. (2010). Relationship between endurance field tests and match performance in young soccer players. Journal of Strength and Conditioning Research, 24(12), 3227-3233.
  • Castellano, J., Blanco-Villase nor, A. Y Álvarez, D. (2011). Contextual Variables and Time-Motion Analysis in Soccer. International Journal of Sports Medicine, 32(6), 415-421.
  • Castellano, J. Y Casamichana, D. (2014). Alternativas en la monitorización de las demandas físicas en fú tbol: pasado, presente. Y futuro. Revista Espanola de Educación Física. Y Deporte, 404, 41-58.
  • Castellano, J. Y Casamichana, D. (2010). Heart rate and motion analysis by GPS in beach soccer. Journal of Sports Science and Medicine, 9(1), 98-103.
  • Castellano, J., Casamichana, D., Calleja-González, J., San Román, J. Y Ostojic, S. M. (2011). Reliability and accuracy of 10 Hz GPS devices for shortdistance exercise. Jo urnal of Sports Science and Medicine, 10(1), 233-234.
  • Castellano, J., Ferná ndez, J. C., Castillo, A.,. Y Casamichana, D. (2010). Fiabilidad intra-participante de diferentes modelos de dispositivos GPS implementados en un partido de fú tbol 7. Cultura, Ciencia. Y Deporte, 5(14), 83-95.
  • Castellano, J., Herná ndez Mendo, A, Morales-Sánchez, V. Y Anguera, M. T. (2007). Optimising a probabilistic model of the development of play in soccer. Quality & Quantity, 41(1), 93-104.
  • Coughlan, G., Green, B., Pook, P., Toolan, E. Y O'Connor, S. (2011). The relationship between physical game demands and injury rehabilitation in international rugby union: A global positioning system analysis. British Journa l of Sports Medicine, 45(4), 323.
  • Coutts, A. Y Duffield, R. (2010). Validity and reliability of GPS devices for measuring movement demands of team sports. Journal of Science and Medicine in Sport, 13(1), 133-135.
  • Coutts, A., Quinn, J., Hocking, J., Castagna, C. Y Rampinini, E. (2010). Match running performance in elite Australian rules football. Journal of Science and Medicine in Sport, 13(5), 543-548.
  • Cunniffe, B., Proctor, W., Baker, J. Y Davis, B. (2009). An evaluation of the physiological demands of elite rugby union using global positioning system tracking software. Journal of Strength and Conditioning Research, 23(4), 1195-1203.
  • Dawson, B., Hopkinson, R., Appleby, B., Stewart, G. Y Roberts, C. (2004). Comparison of training activities and game demands in the Australian Football League. Journal of Science and Me dicine in Sport, 7(3), 292-301.
  • Di Salvo, V., Gregson, W., Atkinson, G., Tordoff, P. Y Drust, B. (2009). Analysis of high intensity activity in premier league soccer. International Journal of Sports Me dicine, 30(3), 205-212.
  • Dobson, B. Y Keogh, J. (2007). Methodological issues for the application of time-motion analysis research. Strength and Conditioning Research, 29(2), 48-55.
  • Duarte, R., Araujo, D., Correia, V. Y Davids, K. (2012). Sports Teams as Superorganisms. Sports Medicine, 42(8), 633-642.
  • Duffield, R., Reid, M., Baker, J. Y Spratford, W. (2010). Accuracy and reliab ility of GPS devices for measurement of movement patterns in confined spaces for court-based sports. Journal of Science and Medicine in Sport, 13(5), 523-525.
  • Dufour W. 1993 Computer-assisted scouting in soccer. En T. Reilly, J. Clarys,. Y A. Stibbe (Eds.), Science and Football II (pp. 160-166). Londres: E. and F.N. Spon.
  • Dwyer, D. B. Y Gabbett, T. J. (2012). Global positioning system data analysis: velocity ranges and a new definition of sprinting for field sport athletes. Journal of Strength and Conditioning Research, 26(3), 818-824
  • Edgecomb, S. J. Y Norton, K. I. (2006). Comparison of global positioning and computerbased tracking syste ms for measuring player movement distance during Australian Football. Journal of Science and Medicine in Sport, 9(1), 25-32.
  • Frencken, W. G., De Poel, H. J. Y Lemmink, K. A. P. M. (2011). Analysis of game dynamics and related game events in 11 vs 11 soccer. 7th World Congress on Science & football (p. 102). Mayo 26-30, Nagoya (Japan).
  • Frencken, W. G., Lemmink, K. Y Delleman, N. (2010). Soccer-specific accuracy and valid ity of the local position measurement (LPM) system. Journal of Science and Medicine in Sport, 13(6), 641-645.
  • Frencken, W., De Poel, H., Visscher, C. Y Lemmink, K. (2012). Variability of inter-team distances associated with match events in elite-standard soccer. Journal of Sports Science. [Pre-publicación electró nica]
  • Gabbett , T. J. (2010). GPS analysis of elite women's field hockey training and competition. Journal of Strength and Conditioning Research, 24(5), 1321-1324.
  • Gaudino, P., laia, F. M., Alberti, G., Hawkins, R. D., Str udwick, A. J. Y Gregson, W. (2014). Systematic bias between running speed and metabolic power data in elite soccer players: Influence of Drill Type. International Journal of Sports Medicine. DOI: 10.1055/s-0033-1355418.
  • Gómez-Piri z, P. T., Jiménez-Reyes, P. Y Ruíz-Ruí z, C. (2011). Relation between total body load and session rating of perceived exertion in professional soccer players. Journal of Strength and Conditioning Research, 25(8), 2100-2103.
  • Gray, A. J., Jenkins, D., Andrews, M. H., Taaffe, D. R. Y Glover, M. L. (2010). Validity and reliability of GPS for measuring distance travelled in fieldbased team sports. Journal of Sports Sciences, 28(12), 1319-1325.
  • Gré haigne, J-F., Godbout, P. Y Zerai, Z. (2011). How the " rapport de forces" evolves in a soccer match: the dynamics of collective decisions in a complex system. Revista de Psicología del Deporte, 20(2), 747-765.
  • Harley, J. A., Barnes, C. A., Portas, M., Lovell, R., Barret, S., Paul, D. Y Weston, M. (2010). Motion analysis of match-play in elite U12 to U16 agegroup soccer players. Journal of Sports Sciences, 28(13), 1391-1397.
  • Hartwig, T. B., Naughton, G. Y Searl, J. (2011). Motion analyses of adolescent rugby union players: A comparison of training and game demands. Journal of Strength and Conditioning Research, 25(4), 966-972.
  • Hausswirth, C., Le Meur, Y., Couturier, A., Bernard, T. Y Brisswalter, J. (2009). Accuracy and Repeatability of the Polar RS800sd to Evaluate Stride Rate and Running Speed. Internationa l Journal of Sports Medicine, 30, 354-359.
  • Hill-Haas, S., Dawson, B., Impellizzeri, F. M.,. Y Coutts, A. (2011). Physiology of small sided games training in football. A systematic review. Sports Medicine 41(3), 199-200.
  • Jennings, D., Cormack, S., Coutts, A. J., Boyd, L. Y Aughey, R. J. (2010a). The validity and reliability of GPS units for measuring distance in team sport specific running patterns. International Journal of Sports Physiology Performance, 5(3), 328-341.
  • Jennings, D., Cormack, S., Coutts, A. J., Boyd, L. Y Aughey, R. J. (2010b). Variability of GPS units for measuring distance in team sport movements. International Journal of Sports Physiology Performance, 5(4), 565-569.
  • Johnston, R. D., Gibson, N. V., Twist, C., Gabbett, T. J., Macnay, S. A. Y Macfarlane, N. G. (2012). Physiological responses to an intensified period of rugby league competition. Journal of Strength and Conditioning Research. Doi: 10.1519/JSC.0b013e31825bb469.
  • Johnston, R. J., Watsford, M. L., Kelly, S. J., Pine, M. J. Y Spurrs, R.W. (2013). The Validity and reliability of 10 Hz and 15 Hz GPS units for assessing athlete movement demands. Journal of Strength and Conditioning Research. Pre-publicación electrónica.
  • Johnston, R. J., Watsford, M. L., Pine, M. J., Spurrs, R. W. Y Sporri, D. (2013). Assessment of 5 Hz and 10 Hz GPS units for measuring athlete movement demands. International Journal of performance analysis in sport, 13, 262-274.
  • Krenn, P. J., Titze, S., Oja, P., Jones, A.,. Y Ogilvie, D. (2011). Use of global positioning systems to study physical activity and the environment: A systematic review. American Journal of Preventive Medicine, 41(5), 508-15.
  • Larsson P. 2003). Global positioning system and sport-specific testing Sports Medicine 33 15 1093-1101.
  • Liebermann, D. G., Katz, L., Hugh es, M. D., Bartlett, R. M., McClements, J. Y Franks, I. M. (2002). Advances in the application of information technology to sport performance. Journal of Sports Sciences, 20(10), 755-769.
  • Little, T. (2 009). Optimizing the use of soccer drills for physiological development. Strength and Conditioning Journal, 31(3), 67-74.
  • MacLellan, C. P., Lovell, D. I. Y Gass, G. C. (2010). Creatine kinase and endocrin e responses of elite players pre, during and post rugby league match play. Journal of Strength and Conditioning Research, 24(11), 2908-2912.
  • MacLeod, H., Morris, J., Nevill, A. Y Sunderland, C. (2009). The validity of a non-differential global positioning system for assessing player movement patterns in field hockey. Journal of Sports Sciences, 27(2), 121-128.
  • Mayhew, S. Y Wenger, H. (1985). Time motion analysis of professional soccer. Journal of Human Movement Studies, 11, 49-52.
  • Misra, P. Y Enge, P. (2006). Global Positioning System: Signals, Measurements, and Performance. Lincoln, MA: Ganga-Jamuna Press.
  • Mohin o, E. (2006). Análisis. Y mitigación del error ionosférico en los sistemas globales de navegación por saté lite con receptores de una frecuencia. Tesis Doctoral: Universidad Complutense de Madrid.
  • O'Donoghue, P. G., Bo yd, M. Y Bleakley, E. W. (2001). Time-motion analysis of elite semi-professional and amateur soccer competition. Journal of Human Movement Studies, 41, 1-12.
  • özgü nen, K. T., Kurdak, S. S., Maughan, R. J., Zeren, C., Korkmaz, S., Yazici, Z., Shirreffs, S. M. (2010). Effect of hot environmental conditions on physical activity patterns and temperature response of football players. Scandinavian Journal of Medicine and Science in Sport, 20(Supl.31), 140-147.
  • Partridge, D., Mosher, R. E. Y Franks I. M. (1993). A computer asisted analysis of technical performance-A comparison of the 1990 World Cup and intercollegiate soccer. En T. Reilly, J. Clarys,. Y A. Stibbe (Eds.), Science and Football II (pp. 221-231). Londres: E. and F. N. Spon.
  • Passos, P., Davids, K., Araujo, D., Paz, N., Minguéns, J. Y Mendes, J. (2011). Networks as a novel tool for studying team ball sports as complex social systems. J ournal of Science and Medicine in Sport, 14, 170-176.
  • Petersen, C., Pyne, D., Dawson, B., Kellet, A. Y Portus, M. (2011). Comparison of training and game demands of national level cricketers. Journal of Strength and Conditioning Research, 25(5), 1306-1311.
  • Petersen, C., Pyne, D., Dawson, B., Portus, M. Y Kellet, A. (2010). Movement patterns in cricket vary by both position and game format. Journal of Sports Sciences, 28(1), 45-52.
  • Petersen, C., Py ne, D., Portus, M. Y Dawson, B. (2009). Validity and reliability of GPS units to monitor cricket-specific movement patterns. International Journal Sports Physiology Performance, 4(3), 381-393.
  • Petersen, C., Pyne, D., Portus, M. Y Dawson, B. (2011). Comparison of player movement patterns between 1-day and test cricket. Journal of Strength and Conditioning Research, 25(5), 1368-1373.
  • Pino, J., Padilla, C., Pé rez, J. J., Moreno, M. I. Y De la Cruz, E. (2008). Innovaciones tecnológicas en el control del entrenamiento. En J. Castellano (Ed.), Fútbol e Innovació n (pp. 15-34). Sevilla: Wanceulen.
  • Portas, M. D., Harley, J. A., Barnes, C. A. Y Rush, C. J. (2010). The validity and reliability of 1-Hz and 5-Hz global positioning systems for linear, multidirectional, and soccer-specific activities. International Journal of Sports Physiology and Performance, 5(4), 448-458.
  • Randers, M. B., Mujika, I., Hewitt, A., Santisteban, J., Bischoff, R., Solano, R., Mohr, M. (2010a). Application of four different football match analysis systems: A comparative study. Jour nal of Sports Sciences, 28(2), 171-182.
  • Redwood-Brown, A., Cranton, W. Y Sunderland, C. (2012). Validation of a Real-Time Video Analysis System for soccer. International Journal of Sports Medicine, 33, 635-640.
  • Reid, M., Duffield, R., Dawson, B., Baker, J. Y Crespo, M. (2008). Quantification of the physiological and performance characteristics of on-court tennis drills. British Journal of Sports Medicine, 42(2), 146-151.
  • Reilly, T. Y Thomas, V. (1976). A motion analysis of work-rate in different positional roles in professional football match-play. Journal of Human Movement Studies, 2, 87-97.
  • Rien zi, E. Drust, B. Reilly, T. Carter, J. E. L. Y Martin, A. 2000). Investigation of anthropometric and work-rate profiles of elite South American international soccer players Journal of Sports and Medical Physical Fitness, 40 2 162-169.
  • Rigden, J. S. (2000). Rabi, scientist and citizen. Cambridge, MA: Harvard University Press.
  • Rowsell, G. J., Coutts, A., Reaburn, P. Y Hill-Haas, S. (2011). Effect of post-match cold-water immersion on subsequent match running performance in junior soccer players during tournament play. Journal of Sports Sciences, 29(1), 1-6.
  • Sampaio J. Y Maça s V. (2012). Measuring Football Tactical Behaviour. International Journal of Sports Medicine, 33, 1-7.
  • Sá nchez-Medina, L. Y Pérez-Caballero, C. (2006). Tecnología GPS al servicio del deporte. Archivos de Medicina del Deporte, XXIII(112), 143-152.
  • Schutz, Y. Y Chambaz, A. (1997). Could a satellite-based navigation system (GPS) be used to assess the physical activity of individuals on earth? European Journal of Clinical Nutrition, 51, 338-339.
  • Schutz, Y. Y H erren, R. (2000). Assessment of speed of human locomotion using a differential satellite global positioning system. Medicine and Science in Sports and Exercise, 32(3), 642-646.
  • Terrier, P., Ladetto, Q., Mermino d, B. Y Schutz, Y. (2000). High-precision satellite positioning system as a new tool to study the biomechanics of human locomotion. Journal of Biomechanics, 33, 1717-1722.
  • Terrier, P., Ladetto, Q., Merminod, B. Y Schutz, Y. (2001). Measurement of the mechanical power of walking by satellite positioning system (GPS). Medicine and Science in Sports and Exercise, 33(11), 1912-1918.
  • Terrier, P. Y Schutz, Y. (2003). Variability of gait patterns during unconstrained walking assessed by satellite positioning (GPS). European Journal of Applied Physiology, 90, 554-561.
  • Thorpe, R. Y Sunderland, C. (2011). Muscle damage, endocrine and immune marker response to a soccer match. Journal of Strength and Conditioning Research. Doi: 10.1519/JSC.0b013e318241e174.
  • Townshend, A. D., Worringham, C. J. Y Stewart, I. B. (2008). Assessment of speed and position during human locom otion using nondifferential GPS. Medicine and Science in Sports and Exercise, 40(1), 124-132.
  • Varley, M. C, Elias, G. P. Y Aughey, R. J. (2012). Current match analysis techniques can underestimate intense periods of high -velocity running. International Journal of Sports Physiology and Performance, 7(2), 183-185.
  • Varley, M. C., Aughey, R. J. Y Pedrana, A. (2011). Accelerations in football: toward a better understanding of high-intensity activity. 7th World Congress on Science & Football (p. 115). Mayo 26-30, Nagoya (Japan).
  • Varley, M. C., Fairweather, I. H. Y Aughey, R. J. (2012). Validity and reliability of GPS for measuring instantaneo us velocity during acceleration, deceleration, and constant motion. Journal of Sports Science, 30(2), 121-127.
  • Von Hü nerbein, K., Hamann, H. J., Rüter, E. Y Wiltschko, W. (2000). A GPS-based system for recording the flight paths of birds. Naturwissenschaften, 87(6), 278-279.
  • Wisbey, B., Montgomery, P. G., Pyne, D. B.,. Y Rattray, B. (2010). Quantifying movement demands of AFL football using GPS tracking. Jou rnal of Science and Medicine in Sport, 13(5), 531-536.
  • Witte, T. H.,. Y Wilson, A. M. (2004). Accuracy of non differential GPS for the determination of speed over ground. Journal of Biomechanics, 37(12), 1891-98.