Cardiorespiratory fitness (CRF) and its relationship with maximum oxygen consumption (VO2max) among 16-year-old junior players at Zakho football club
DOI:
https://doi.org/10.26418/tajor.v3i1.87358Keywords:
Cardiorespiratory, Fitness, Junior Football, VO2 max, Heart Rate.Abstract
Background and Study Aim. Cardiorespiratory fitness (CRF) plays a crucial role in modern football performance, particularly in youth development where proper assessment and monitoring can significantly impact long-term athletic potential. While laboratory-based measurements of maximum oxygen consumption (VO2 max) are accurate, there is a need to validate practical field-based testing methods for youth players, especially in regions with unique environmental conditions like Iraqi Kurdistan. The present study investigated the relationship between CRF and VO2 ma among 16-year-old football players at Zakho Football Club.
Material and Methods. The descriptive correlational method was employed to examine the relationship between cardiorespiratory fitness CRF and VO2 max in 16-year-old junior football players. A random sample of twenty players was selected from a population of thirty-two players. The research utilized multiple assessment tools including the Cooper 12-minute test for CRF evaluation, heart rate monitoring through Garmin fÄ“nix ® 7 devices for measuring cardiovascular responses, and Cooper"™s formula for VO2 max estimation. Testing procedures were standardized and conducted at Dalal Sports Stadium during evening sessions to minimize environmental effects. Data analysis employed descriptive statistics and correlation coefficients.
Results. The results revealed varying levels of cardiorespiratory fitness among players, with the majority demonstrating above-average performance levels. Statistical analysis showed a strong positive correlation between Cooper test performance and VO2 max values, validating the effectiveness of field-based testing for assessing cardiorespiratory fitness in Junior players. Heart rate response patterns indicated diverse cardiovascular adaptations across performance levels, suggesting the need for individualized training approaches.
Conclusion. The findings contribute to understanding the relationship between field-based fitness assessments and physiological responses in Junior football, particularly in regions with unique environmental conditions. This research provides practical insights for optimizing Junior football development programs while highlighting the importance of considering individual adaptation patterns in training design.
References
Arcos, A. L., MartÃnez-Santos, R., Yanci, J., & Mendiguchia, J. (2020). Monitoring perceived respiratory and muscular exertions and physical fitness in young professional soccer players during a 32-week period. Kinesiology, 52(1), 85-93. https://doi.org/10.26582/k.49.2.12
Bandyopadhyay, A. (2015). Validity of Cooper's 12-minute run test for estimation of maximum oxygen uptake in male university students. Biology of Sport, 32(1), 59-63. https://doi.org/10.5604/20831862.1127283
Beato, M., Drust, B., & Iacono, A. D. (2021). Implementing high-speed running and sprinting training in professional soccer. International Journal of Sports Medicine, 42(4), 295-299. https://doi.org/10.1055/a-1302-7968
Bradley, P. S., Sheldon, W., Wooster, B., Olsen, P., Boanas, P., & Krustrup, P. (2009). High-intensity running in English FA Premier League soccer matches. Journal of Sports Sciences, 27(2), 159-168. https://doi.org/10.1080/02640410802512775
Brink, M. S., Visscher, C., Arends, S., Zwerver, J., Post, W. J., & Lemmink, K. A. (2010). Monitoring stress and recovery: new insights for the prevention of injuries and illnesses in elite youth soccer players. British Journal of Sports Medicine, 44(11), 809-815. https://doi.org/10.1136/bjsm.2009.069476
Cardinale, M., & Varley, M. C. (2017). Wearable training-monitoring technology: Applications, challenges, and opportunities. International Journal of Sports Physiology and Performance, 12(s2), S2-55. https://doi.org/10.1123/ijspp.2016-0423
Carling, C., Bloomfield, J., Nelsen, L., & Reilly, T. (2008). The role of motion analysis in elite soccer. Sports Medicine, 38(10), 839-862. https://doi.org/10.2165/00007256-200838100-00004
Clemente, F. M., Silva, R., Castillo, D., Los Arcos, A., Mendes, B., & González-Fernández, J. T. (2019). Weekly load variations of distance-based variables in professional soccer players: A full-season study. International Journal of Environmental Research and Public Health, 16(19), 3534. https://doi.org/10.3390/ijerph17093300
Dellal, A., Owen, A., Wong, D. P., Krustrup, P., van Exsel, M., & Mallo, J. (2012). Technical and physical demands of small vs. large sided games in relation to playing position in elite soccer. Human Movement Science, 31(4), 957-969. https://doi.org/10.1016/j.humov.2011.08.013
Dello Iacono, A., & Beato, M. (2020). Strength training in soccer: A systematic review. International Journal of Sports Physiology and Performance, 15(9), 1206-1222. https://doi.org/10.3390/life14091081
Di Salvo, V., Baron, R., Tschan, H., Montero, F. C., Bachl, N., & Pigozzi, F. (2007). Performance characteristics according to playing position in elite soccer. International Journal of Sports Medicine, 28(3), 222-227. https://doi.org/10.1055/s-2006-924294
Gabbett, T. J. (2016). The training-injury prevention paradox: should athletes be training smarter and harder? British Journal of Sports Medicine, 50(5), 273-280. https://doi.org/10.1136/bjsports-2015-095788
Gilgenâ€Ammann, R., Schweizer, T., & Wyss, T. (2019). Accuracy of the multisensory wristwatch Polar Vantage's estimation of energy expenditure in various activities: Instrument validation study. JMIR mHealth and uHealth, 7(10), e14534. https://doi.org/10.2196/14534
Grant, S., Corbett, K., Amjad, A. M., Wilson, J., & Aitchison, T. (1995). A comparison of methods of predicting maximum oxygen uptake. British Journal of Sports Medicine, 29(3), 147-152. https://doi.org/10.1136/bjsm.29.3.147
Hill-Haas, S. V., Dawson, B., Impellizzeri, F. M., & Coutts, A. J. (2011). Physiology of small-sided games training in football. Sports Medicine, 41(3), 199-220. https://doi.org/10.2165/11539740-000000000-00000
Impellizzeri, F. M., Rampinini, E., & Marcora, S. M. (2005). Physiological assessment of aerobic training in soccer. Journal of Sports Sciences, 23(6), 583-592. https://doi.org/10.1080/02640410400021278
Lloyd, R. S., Oliver, J. L., Faigenbaum, A. D., Howard, R., De Ste Croix, M. B., Williams, C. A., ... & Myer, G. D. (2016). Long-term athletic development-part 1: A pathway for all youth. The Journal of Strength & Conditioning Research, 30(6), 1491-1509. https://doi.org/10.1519/JSC.0000000000000756
Malina, R. M., Rogol, A. D., Cumming, S. P., Coelho e Silva, M. J., & Figueiredo, A. J. (2015). Biological maturation of youth athletes: assessment and implications. British Journal of Sports Medicine, 49(13), 852-859. https://doi.org/10.1136/bjsports-2015-094623
Maughan, R. J., Otani, H., & Watson, P. (2020). Influence of relative humidity on prolonged exercise capacity in a warm environment. European Journal of Applied Physiology, 120(1), 107-114. https://doi.org/10.1007/s00421-011-2206-7
Mendez-Villanueva, A., Buchheit, M., Simpson, B., & Bourdon, P. C. (2011). Match play intensity distribution in youth soccer. International Journal of Sports Medicine, 32(07), 523-528. https://doi.org/10.1055/s-0032-1306323
Mohr, M., Nybo, L., Grantham, J., & Racinais, S. (2012). Physiological responses and physical performance during football in the heat. PloS one, 7(6), e39202. https://doi.org/10.1371/journal.pone.0039202
Nassis, G. P., Brito, J., Dvorak, J., Chalabi, H., & Racinais, S. (2015). The association of environmental heat stress with performance: analysis of the 2014 FIFA World Cup Brazil. British Journal of Sports Medicine, 49(9), 609-613. https://doi.org/10.1136/bjsports-2014-094449
Nobari, H., Aquino, R., Clemente, F. M., Khalafi, M., Adsuar, J. C., & Pérez-Gómez, J. (2021). Description of acute and chronic load, training monotony and strain over a season and its relationships with well-being status: A study in elite under-16 soccer players. Physiology & Behavior, 232, 113340. https://doi.org/10.1016/j.physbeh.2020.113117
Philippaerts, R. M., Vaeyens, R., Janssens, M., Van Renterghem, B., Matthys, D., Craen, R., & Malina, R. M. (2006). The relationship between peak height velocity and physical performance in youth soccer players. Journal of Sports Sciences, 24(3), 221-230. https://doi.org/10.1080/02640410500189371
Racinais, S., Blonc, S., & Hue, O. (2012). Effects of active warm-up and diurnal increase in temperature on muscular power. Medicine & Science in Sports & Exercise, 37(12), 2134-2139. https://doi.org/10.1249/01.mss.0000179099.81706.11
Rampinini, E., Impellizzeri, F. M., Castagna, C., Coutts, A. J., & Wisløff, U. (2008). Technical performance during soccer matches of the Italian Serie A league: Effect of fatigue and competitive level. Journal of Science and Medicine in Sport, 12(1), 227-233. https://doi.org/10.1016/j.jsams.2007.10.002
Schmitz, B., Pfeifer, C., Kreitz, K., Borowski, M., Faldum, A., & Brand, S. M. (2018). The Yo-Yo Intermittent Tests: A systematic review and structured compendium of test results. Frontiers in Physiology, 9, 870. https://doi.org/10.3389/fphys.2018.00870
Stølen, T., Chamari, K., Castagna, C., & Wisløff, U. (2005). Physiology of soccer: an update. Sports Medicine, 35(6), 501-536. https://doi.org/10.2165/00007256-200535060-00004
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