目的：本研究之目的在於探討少棒選手垂直跳參數與跑壘表現之相關，並比較不同年齡的少棒選手垂直跳、衝刺、跑壘表現以及跑壘效率之差異。方法：招募志願參與本研究之國小四至六年級少棒選手28名，透過測力板進行反向跳與蹲踞跳，收取垂直跳的地面反作用力訊號，進行21.34公尺和42.67公尺直線衝刺及跑壘時間的測驗收取跑壘表現參數。以皮爾森積差相關進行相關性分析。使用單因子變異數分析比較不同年級間的差異，如達顯著使用Bonferroni法進行事後比較。結果：反向跳跳躍高度、推蹬峰值力量、推蹬峰值功率、修正式反應力指數以及蹲踞跳跳躍高度、推蹬峰值力量、推蹬峰值功率與直線衝刺時間達顯著相關 (p < .05)。反向跳跳躍高度、推蹬峰值力量、推蹬峰值功率、反應力指數以及蹲踞跳跳躍高度、推蹬峰值力量、推蹬峰值功率與跑壘時間皆達顯著相關 (p < .05)。沒有任何參數與跑壘效率有關。六年級的蹲踞跳峰值功率顯著比四年級高，其餘垂直跳參數不同年級間沒有差異。六年級的衝刺與跑壘速度顯著較快。結論：少棒選手衝刺與跑壘會受到發展成熟而有較好表現，且衝刺與跑壘的能力和垂直跳向心動作推蹬能力有關。建議少棒教練在訓練少棒選手更快的跑壘表現時，可以增強其向地面推蹬的力量與技術，並且適時加入快速反向動作訓練來刺激伸張收縮循環的機制，可以增強其向地面推蹬的力量與技術。

Purpose: This study investigated the correlation between vertical jump parameters and base running performance of youth baseball players, and compared the differences in vertical jump, sprinting, base running performance, and base running efficiency among youth baseball players of different grades. Method: Twenty-eight youth baseball players in grades 4 to 6 were recruited to participate in this study. The ground reaction force signals of countermovement jump and squat jump were collected via the force platform, and the base running performance parameters were collected from the tests of the 21.34 meters and 42.67 meters straight-line sprints and the base running times. Correlation analysis was performed using Pearson's correlation. The differences between grades were compared by one-way analysis of variance (ANOVA). Results: Jump height, peak force, peak power, and modified reactivity strength index of countermovement jump and jump height, peak force, peak power of squat jump were significantly correlated with straight-line sprinting (p < .05). Jump height, peak force, peak power, and modified reactivity strength index of countermovement jump and jump height, peak force, peak power of squat jump were all significantly correlated with base running time (p < .05). No parameter was correlated with base running efficiency. Peak power of squat jump of grade six players was significantly higher than grade four. Other vertical jump parameters were not different between grades. The speed of base running of grade six was faster. Conclusion: The performance of sprint and base running in youth baseball players will be enhanced by developmental maturity. The ability to sprint and base running will be related to the ability to push the pedal in the vertical jump centripetal maneuver. It is suggested that youth baseball coaches work on the strength and technique of pushing to the ground when training youth baseball players to run the bases faster. Appropriately incorporation of rapid countermovement training to stimulate the mechanism of the stretch-shortening cycle could enhance the strength and technique of propulsion.

中華民國棒球協會 (2022)。中華民國棒球規則。作者。
王令儀、王思宜 (2022)。跳躍動作中離心階段的生物力學特性對跳躍表現之影響。中華體育季刊，36(4)，413-421。https://doi.org/10.6223/qcpe.202212_36(4).0008
[Wang, L.-I., & Wang, S.-Y. (2022). Effects of biomechanics characteristics during eccentric phase of jumping action on jumping performance. Quarterly of Chinese Physical Education, 36(4), 413-421.]
王維平、陳重佑 (2020)。衝刺跑的著地時間與地面反作用力。中華體育季刊，34(3)，177-184。https://doi.org/10.6223/qcpe.202009_34(3).0004
[Wang, W.-P., & Chen, C.-Y. (2020). Contact time and ground reaction force during the acceleration phase of sprinting. Quarterly of Chinese Physical Education, 34(3), 177-184.]
王哲彥、楊國煌、張曉昀 (2008)。增強式訓練對運動員下肢爆發力的影響。臺中教育大學體育學系系刊，(3)，98-103。https://doi.org/10.29781/NTCUPE.200808.0019
[Wang, Z.-Y., Yang, K.-H., & Chang, H.-Y. (2008). Effects of plyometric training on power of lower extremities in athletes. N.T.C.U Physical Education, (3), 98-103.]
張晉榮、陳重佑 (2019)。評估下肢牽張縮短循環效果的方法。中華體育季刊，33(1)，33-40。https://doi.org/10.3966/102473002019033301005
[Chang, C.-J., & Chen, C.-Y., The methods to assess lower extremities stretch shortening cycle utilization. Quarterly of Chinese Physical Education, 33(1), 33-40.]
孟範武、陳建廷、張淳皓、呂惟帆 (2014)。敏捷性與跳躍瞬發力之關聯分析。中原體育學報，(4)，71-77。https://doi.org/10.6646/CYPEJ.2014.4.71
[Meng, W.-F., Chen, C.-T., Chang, C.-H., & Lu, W.-F. (2014). A Relational Analysis between Agility and Force-Slope of Jumping. Chung Yuan Physical Education Journal, (4), 71-77.]
林威名、洪敏豪、吳政文、何金山 (2017)。橄欖球選手啟動速度與下肢爆發力之相關性分析。運動表現期刊，4(2)，99-104。https://doi.org/10.3966/240996512017120402004
[Lin, W.-M., Hung, M.-H., Wu, C.-W., & Ho, C.-S. (2017). Relationships between start speed and lower limbs power in rugby players. Journal of Sports Performance, 4(2), 99-104.]
涂國誠 (2006)。羽球運動專項體能的速度訓練。成大體育，39(2)，12-18。http://140.116.207.99/handle/987654321/131763
[Tu, K.-C. (2006). Speed training for badminton-specific fitness. National Cheng Kung University Physical Education Research, 39(2), 12-18.]
翁誌誼、陳樹屏、廖佳慶 (2012)。增強式訓練對籃球隊男童爆發力、速度及敏捷性之影響。運動教練科學，(27)，17-29。https://doi.org/10.6194/SCS.2012.27.02
[Weng, C.-Y., Chen, S.-P., & Liao, J.-C. (2012). Plyometric Training Effects on Power, Speed and Agility in 6th Grade Male Basketball Players. Sports Coaching Science, (27), 17-29.]
莊英萬 (2002)。棒球跑壘的研究及訓練。中華體育季刊，16(4)，39-44。https://doi.org/10.6223/qcpe.1604.200212.2206
[Chuang, Y.-W. (2002). Research and training of baseball baserunning. Quarterly of Chinese Physical Education, 16(4), 39-44.]
蔡宗憲 (2014)。不同打擊站姿對跑壘反應時間之影響。嘉大體育健康休閒期刊，13(3)，21-28。https://doi.org/10.6169/NCYUJPEHR.2014.13.3.03
[Tsai, C.-H. (2014). The impact of different hitting stances on base running reaction time. NCYU Physical Education, Health & Recreation Journal, 13(3), 21-28.]
鍾宇政 (2007)。不同撃球狀況下選手跑壘速度之分析。嘉大體育健康休閒期刊，6(1)，93-98。https://doi.org/10.6169/NCYUJPEHR.6.1.12
[Jong, Y.-J. (2007). Analysis of base running speed of players under different hitting conditions. NCYU Physical Education, Health & Recreation Journal, 6(1), 93-98.]
Aksović, N., Kocić, M., Berić, D., & Bubanj, S. (2020). Explosive power in basketball players. Facta Universitatis, Series: Physical Education and Sport, (1), 119-134. https://doi.org/10.22190/FUPES200119011A
Blazevich A. J. (2006). Effects of physical training and detraining, immobilisation, growth and aging on human fascicle geometry. Sports medicine (Auckland, N.Z.), 36(12), 1003–1017. https://doi.org/10.2165/00007256-200636120-00002
Brown, K. A., Patel, D. R., & Darmawan, D. (2017). Participation in sports in relation to adolescent growth and development. Translational pediatrics, 6(3), 150–159. https://doi.org/10.21037/tp.2017.04.03
Chuang, C. H., Wu, C. W., & Lin, K. C. (2021). Reliability and Differences of Jump Kinetics Related to Different Load in College Male Athletes. Athens Journal of Sports, 8(4). https://doi.org/10.30958/ajspo.8-4-3
Coleman, A. E. (2000). 52-week baseball training. Human Kinetics. https://cir.nii.ac.jp/crid/1130000797812229888
Coleman, A. E., & Amonette, W. E. (2012). Pure acceleration is the primary determinant of speed to first-base in major-league baseball game situations. Journal of Strength and Conditioning Research, 26(6), 1455-1460. https://doi.org/10.1519/JSC.0b013e3182541d56
Coleman, E. (2007). Running speed in professional baseball. Strength and Conditioning Journal, 29(3), 72-76. https://doi.org/10.1519/00126548-200706000-00011
Comfort, P., Stewart, A., Bloom, L., & Clarkson, B. (2014). Relationships between strength, sprint, and jump performance in well-trained youth soccer players. Journal of strength and conditioning research, 28(1), 173–177. https://doi.org/10.1519/JSC.0b013e318291b8c7
Conlon, J., Haff, G. G., Nimphius, S., Tran, T., & Newton, R. U. (2013). Vertical jump velocity as a determinant of speed and agility performance. Journal of Australian Strength and Conditioning, 21, 88-90. https://ro.ecu.edu.au/ecuworks2013/281
Cronin, J., & Hansen, K. T. (2006). Resisted sprint training for the acceleration phase of sprinting. Strength and Conditioning Journal, 28(4), 42-51. http://dx.doi.org/10.1519/00126548-200608000-00006
Crotin, R. (2009). Game speed training in baseball. Strength and Conditioning Journal, 31(2), 13-25. http://dx.doi.org/10.1519/SSC.0b013e31819d444e
Garnacho-Castaño, M. V., López-Lastra, S., & Maté-Muñoz, J. L. (2015). Reliability and validity assessment of a linear position transducer. Journal of sports science and medicine, 14(1), 128. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4306764/
Giroux, C., Rabita, G., Chollet, D., & Guilhem, G. (2016). Optimal balance between force and velocity differs among world-class athletes. Journal of applied biomechanics, 32(1), 59-68. https://doi.org/10.1123/jab.2015-0070
Hackett, D. A., He, W., Orr, R., & Sanders, R. (2020). Effects of age and sex on field-based measures of muscle strength and power of the upper and lower body in adolescents. Journal of sports sciences, 39(9), 955-960. https://doi.org/10.1080/02640414.2020.1851926
Häkkinen, K. (1989). Neuromuscular and hormonal adaptations during strength and power training. A review. The Journal of sports medicine and physical fitness, 29(1), 9-26. https://pubmed.ncbi.nlm.nih.gov/2671501/
Handelsman, D. J., Hirschberg, A. L., & Bermon, S. (2018). Circulating Testosterone as the Hormonal Basis of Sex Differences in Athletic Performance. Endocrine reviews, 39(5), 803–829. https://doi.org/10.1210/er.2018-00020
Hara, M., Shibayama, A., Takeshita, D., Hay, D. C., & Fukashiro, S. (2008). A comparison of the mechanical effect of arm swing and countermovement on the lower extremities in vertical jumping. Human movement science, 27(4), 636-648. https://doi.org/10.1016/j.humov.2008.04.001
Harrison, A. J., & Gaffney, S. (2001). Motor development and gender effects on stretch-shortening cycle performance. Journal of science and medicine in sport, 4(4), 406–415. https://doi.org/10.1016/s1440-2440(01)80050-5
Hori, N., Newton, R. U., Nosaka, K., & McGuigan, M. R. (2006). Comparison of different methods of determining power output in weightlifting exercises. Strength and Conditioning Journal, 28(2), 34-40. http://dx.doi.org/10.1519/00126548-200604000-00006
Hunter, J. P., Marshall, R. N., & McNair, P. J. (2005). Relationships between ground reaction force impulse and kinematics of sprint-running acceleration. Journal of applied biomechanics, 21(1), 31–43. https://doi.org/10.1123/jab.21.1.31
Jarvis, P., Turner, A., Read, P., & Bishop, C. (2022). Reactive strength index and its associations with measures of physical and sports performance: A systematic review with meta-analysis. Sports medicine, 52(2), 301-330. https://doi.org/10.1007/s40279-021-01566-y
Kale, M., Aşçi, A., Bayrak, C., & Açikada, C. (2009). Relationships among jumping performances and sprint parameters during maximum speed phase in sprinters. Journal of strength and conditioning research, 23(8), 2272–2279. https://doi.org/10.1519/JSC.0b013e3181b3e182
Kawamori, N., Nosaka, K., & Newton, R. U. (2013). Relationships between ground reaction impulse and sprint acceleration performance in team sport athletes. Journal of strength and conditioning research, 27(3), 568–573. https://doi.org/10.1519/JSC.0b013e318257805a
Köklü, Y., Alemdaroğlu, U., Özkan, A., Koz, M., & Ersöz, G. (2015). The relationship between sprint ability, agility and vertical jump performance in young soccer players. Science & Sports, 30(1), e1-e5. https://doi.org/10.1016/j.scispo.2013.04.006
Kubo, K., Kanehisa, H., Kawakami, Y., & Fukanaga, T. (2001). Growth changes in the elastic properties of human tendon structures. International journal of sports medicine, 22(2), 138–143. https://doi.org/10.1055/s-2001-11337
Lloyd, R. S., Read, P., Oliver, J. L., Meyers, R. W., Nimphius, S., & Jeffreys, I. (2013). Considerations for the development of agility during childhood and adolescence. Strength and Conditioning Journal, 35(3), 2-11. https://doi.org/10.1519/SSC.0b013e31827ab08c
Loko, J., Aule, R., Sikkut, T., Ereline, J., & Viru, A. (2000). Motor performance status in 10 to 17-year-old Estonian girls. Scandinavian journal of medicine & science in sports, 10(2), 109–113. https://doi.org/10.1034/j.1600-0838.2000.010002109.x
Loturco, I., DʼAngelo, R. A., Fernandes, V., Gil, S., Kobal, R., Cal Abad, C. C., Kitamura, K., & Nakamura, F. Y. (2015). Relationship between sprint ability and loaded/unloaded jump tests in elite sprinters. Journal of strength and conditioning research, 29(3), 758–764. https://doi.org/10.1519/JSC.0000000000000660
Loturco, I., Suchomel, T., Bishop, C., Kobal, R., Pereira, L. A., & McGuigan, M. (2019). One-repetition-maximum measures or maximum bar-power output: Which is more related to sport performance?. International journal of sports physiology and performance, 14(1), 33-37. https://doi.org/10.1123/ijspp.2018-0255
Marginson, V., Rowlands, A. V., Gleeson, N. P., & Eston, R. G. (2005). Comparison of the symptoms of exercise-induced muscle damage after an initial and repeated bout of plyometric exercise in men and boys. Journal of Applied physiology, 99(3), 1174-1181. https://doi.org/10.1152/japplphysiol.01193.2004
Marquardt, A., Wong, M. A., Watkins, C. M., Barillas, S. R., Galpin, A. J., Coburn, J. W., & Brown, L. E. (2018). Effects of starting stance on base running sprint speed in softball players. International Journal of Exercise Science, 11(6), 179. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5955303/
McMahon, J. J., Suchomel, T. J., Lake, J. P., & Comfort, P. (2018). Understanding the key phases of the countermovement jump force-time curve. Strength and Conditioning Journal, 40(4), 96-106. https://doi.org/10.1519/SSC.0000000000000375
Mero, A. (1988). Force-Time Characteristics and Running Velocity of Male Sprinters during the Acceleration Phase of Sprinting. Research Quarterly for Exercise and Sport, 59(2), 94–98. https://doi.org/10.1080/02701367.1988.10605484
Meyers, R. W., Moeskops, S., Oliver, J. L., Hughes, M. G., Cronin, J. B., & Lloyd, R. S. (2019). Lower-Limb Stiffness and Maximal Sprint Speed in 11-16-Year-Old Boys. Journal of strength and conditioning research, 33(7), 1987–1995. https://doi.org/10.1519/JSC.0000000000002383
Miyaguchi, K., Demura, S., Nagai, K., & Uchida, Y. (2011). Comparison of base running in baseball players and track-and-field athletes. Health, 3(01), 26. http://dx.doi.org/10.4236/health.2011.31005
Morin, J. B., Edouard, P., & Samozino, P. (2011). Technical ability of force application as a determinant factor of sprint performance. Medicine and science in sports and exercise, 43(9), 1680–1688. https://doi.org/10.1249/MSS.0b013e318216ea37
Morin, J. B., Gimenez, P., Edouard, P., Arnal, P., Jiménez-Reyes, P., Samozino, P., Brughelli, M., & Mendiguchia, J. (2015). Sprint Acceleration Mechanics: The Major Role of Hamstrings in Horizontal Force Production. Frontiers in physiology, 6, 404. https://doi.org/10.3389/fphys.2015.00404
Moura, T. B. M. A., & Okazaki, V. H. A. (2022). Kinematic and kinetic variable determinants on vertical jump performance: a review. MOJ Sports Medicine, (5), 1. https://medcraveonline.com/MOJSM/MOJSM-05-00113.pdf
Murata, M., Takai, Y., Kanehisa, H., Fukunaga, T., & Nagahara, R. (2018). Spatiotemporal and Kinetic Determinants of Sprint Acceleration Performance in Soccer Players. Sports (Basel, Switzerland), 6(4), 169. https://doi.org/10.3390/sports6040169
Nagahara, R., Kanehisa, H., & Fukunaga, T. (2020). Ground reaction force across the transition during sprint acceleration. Scandinavian journal of medicine & science in sports, 30(3), 450–461. https://doi.org/10.1111/sms.13596
O'Brien, T. D., Reeves, N. D., Baltzopoulos, V., Jones, D. A., & Maganaris, C. N. (2010). In vivo measurements of muscle specific tension in adults and children. Experimental physiology, 95(1), 202–210. https://doi.org/10.1113/expphysiol.2009.048967
Owen, N. J., Watkins, J., Kilduff, L. P., Bevan, H. R., & Bennett, M. A. (2014). Development of a criterion method to determine peak mechanical power output in a countermovement jump. Journal of strength and conditioning research, 28(6), 1552–1558. https://doi.org/10.1519/JSC.0000000000000311
Papaiakovou, G., Giannakos, A., Michailidis, C., Patikas, D., Bassa, E., Kalopisis, V., Anthrakidis, N., & Kotzamanidis, C. (2009). The effect of chronological age and gender on the development of sprint performance during childhood and puberty. Journal of strength and conditioning research, 23(9), 2568–2573. https://doi.org/10.1519/JSC.0b013e3181c0d8ec
Pitlović, V., Sarić, G., Pitlović, H., Jovanović, S., & Jurisić, D. (2013). A correlation of peak height velocity and olecranon apophysis ossification assessed by ultrasound. Collegium antropologicum, 37(4), 1285–1289. https://pubmed.ncbi.nlm.nih.gov/24611346/
PONY Baseball. (2023). 2023 Rules and Regulations. PONY Baseball, Inc.TM of Washington.
Quatman-Yates, C. C., Quatman, C. E., Meszaros, A. J., Paterno, M. V., & Hewett, T. E. (2012). A systematic review of sensorimotor function during adolescence: a developmental stage of increased motor awkwardness?. British journal of sports medicine, 46(9), 649–655. https://doi.org/10.1136/bjsm.2010.079616
Radnor, J. M., Oliver, J. L., Waugh, C. M., Myer, G. D., & Lloyd, R. S. (2020). The Influence of Maturity Status on Muscle Architecture in School-Aged Boys. Pediatric exercise science, 32(2), 89–96. https://doi.org/10.1123/pes.2019-0201
Ross, A., Leveritt, M., & Riek, S. (2001). Neural influences on sprint running: training adaptations and acute responses. Sports medicine (Auckland, N.Z.), 31(6), 409–425. https://doi.org/10.2165/00007256-200131060-00002
Rossi, J., Slotala, R., Samozino, P., Morin, J. B., & Edouard, P. (2017). Sprint acceleration mechanics changes from children to adolescent. Computer Methods in Biomechanics and Biomedical Engineering, 20(sup1), S181–S182. https://doi.org/10.1080/10255842.2017.1382922
Seger, J. Y., & Thorstensson, A. (2000). Muscle strength and electromyogram in boys and girls followed through puberty. European journal of applied physiology, 81(1-2), 54–61. https://doi.org/10.1007/PL00013797
Sekine, Y., & Okada, J. (2016). Effects of Resisted Sprint Training on Sprint Performance in High School Baseball Players. American Journal of Sports Science, 4(5), 90-97. https://doi.org/10.11648/j.ajss.20160405.13
Shrout, P. E., & Fleiss, J. L. (1979). Intraclass correlations: uses in assessing rater reliability. Psychological bulletin, 86(2), 420. https://doi.org/10.1037/0033-2909.86.2.420
Spaniol, F. J. (2009). Baseball athletic test: A baseball-specific test battery. Strength & Conditioning Journal, 31(2), 26-29. https://doi.org/10.1519/SSC.0b013e31819d3af8
Szymanski, D. J., & Fredrick, G. A. (2001). Baseball (part II): A periodized speed program. Strength and Conditioning Journal, 23(2), 44. http://dx.doi.org/10.1519/00126548-200104000-00010
Taber, C., Bellon, C., Abbott, H., & Bingham, G. E. (2016). Roles of maximal strength and rate of force development in maximizing muscular power. Strength & Conditioning Journal, 38(1), 71-78. https://doi.org/10.1519/SSC.0000000000000193
Thieschäfer, L., & Büsch, D. (2022). Development and trainability of agility in youth: A systematic scoping review. Frontiers in Sports and Active Living, 4, 952779. https://doi.org/10.3389/fspor.2022.952779
Thompson, C. J., & Bemben, M. G. (1999). Reliability and comparability of the accelerometer as a measure of muscular power. Medicine and science in sports and exercise, 31(6), 897-902. https://doi.org/10.1097/00005768-199906000-00020
Tonson, A., Ratel, S., Le Fur, Y., Cozzone, P., & Bendahan, D. (2008). Effect of maturation on the relationship between muscle size and force production. Medicine and science in sports and exercise, 40(5), 918–925. https://doi.org/10.1249/MSS.0b013e3181641bed
Tsuno, T., Nagahara, R., Mizutani, M., Matsuo, A., Nakamoto, H., & Maeda, A. (2016, November). Relationship of base-running performance with running direction and its change. In ISBS-Conference Proceedings Archive. https://ojs.ub.uni-konstanz.de/cpa/article/view/6968
Van Hooren, B., & Zolotarjova, J. (2017). The Difference Between Countermovement and Squat Jump Performances: A Review of Underlying Mechanisms With Practical Applications. Journal of strength and conditioning research, 31(7), 2011–2020. https://doi.org/10.1519/JSC.0000000000001913
Vänttinen, T., Blomqvist, M., Nyman, K., & Häkkinen, K. (2011). Changes in body composition, hormonal status, and physical fitness in 11-, 13-, and 15-year-old Finnish regional youth soccer players during a two-year follow-up. Journal of strength and conditioning research, 25(12), 3342–3351. https://doi.org/10.1519/JSC.0b013e318236d0c2
Viru, A., Loko, J., Harro, M., Volver, A., Laaneots, L., & Viru, M. (1999). Critical periods in the development of performance capacity during childhood and adolescence. European Journal of Physical Education, 4(1), 75-119. https://doi.org/10.1080/1740898990040106
Wisløff, U., Castagna, C., Helgerud, J., Jones, R., & Hoff, J. (2004). Strong correlation of maximal squat strength with sprint performance and vertical jump height in elite soccer players. British journal of sports medicine, 38(3), 285–288. https://doi.org/10.1136/bjsm.2002.002071
Young, W. B., James, R., & Montgomery, I. (2002). Is muscle power related to running speed with changes of direction?. Journal of sports medicine and physical fitness, 42(3), 282-288. https://pubmed.ncbi.nlm.nih.gov/12094116/
Young, W., Mc Lean, B., & Ardagna, J. (1995). Relationship between strength qualities and sprinting performance. Journal of sports medicine and physical fitness, 35(1), 13-19. http://europepmc.org/abstract/MED/7474987
Yu, J., Sun, Y., Yang, C., Wang, D., Yin, K., Herzog, W., & Liu, Y. (2016). Biomechanical Insights Into Differences Between the Mid-Acceleration and Maximum Velocity Phases of Sprinting. Journal of strength and conditioning research, 30(7), 1906–1916. https://doi.org/10.1519/JSC.0000000000001278
Zemková, E., & Hamar, D. (2014). Age-related changes in agility time in children and adolescents. International Journal of Science and Research, 3(11), 280-285. https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=4197d8f375f0b74f779267689aeb88301d442c3c