International Journal of Human Movement and Sports Sciences 8(5): 229-234, 2020 http://www.hrpub.org DOI: 10.13189/saj.2020.080510 Developing a New Model of Resistance-based Strength Train and Its Effects on Junior Athletes' Tennis Serve Performance Rina Ambar Dewanti 1,* , Beltasar Tarigan 1 , Dian Budiana 1 , Yudy Hendrayana 1 , Lutfi Nur 2 1 Department of Sports Education, School of Postgraduate Studies, Universitas Pendidikan Indonesia, 40154, Bandung, Indonesia 2 Department of Elementary Teacher Education, Tasikmalaya Campus, Universitas Pendidikan Indonesia, 40154, Bandung, Indonesia Received July 1, 2020; Revised September 17, 2020; Accepted September 29, 2020 Cite This Paper in the following Citation Styles (a): [1] Rina Ambar Dewanti, Beltasar Tarigan, Dian Budiana, Yudy Hendrayana, Lutfi Nur , "Developing a New Model of Resistance-based Strength Train and Its Effects on Junior Athletes’ Tennis Serve Performance," International Journal of Human Movement and Sports Sciences, Vol. 8, No. 5, pp. 229 - 234, 2020. DOI: 10.13189/saj.2020.080510. (b): Rina Ambar Dewanti, Beltasar Tarigan, Dian Budiana, Yudy Hendrayana, Lutfi Nur (2020). Developing a New Model of Resistance-based Strength Train and Its Effects on Junior Athletes’ Tennis Serve Performance. International Journal of Human Movement and Sports Sciences, 8(5), 229 - 234. DOI: 10.13189/saj.2020.080510. Copyright©2020 by authors, all rights reserved. Authors agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0 International License Abstract This study was aimed at developing a new model of resistance-based strength training for junior tennis athletes and examining its effectiveness on their serve performance compared to traditional model of training. It is a Research and Development study focusing on developing, validating, revising, and testing the model of training. In testing phase, effectiveness test was accomplished to examine the effectiveness of the new training model and compared to the effectiveness of the traditional model. There were 60 junior athletes contributing to this study. The data were gathered by distributing questionnaires to reveal the convenience and attractiveness of the model developed and using Collang Smart Tennis Racket Sensor Tracker Motion Analyzer to reveal the tennis athletes’ serve performance. The data were analyzed by employing descriptive statistic and t-test. In terms of convenience and attractiveness, this study revealed that the use of resistance training for junior tennis athletes showed good results. T-test proved that this new model was more effective in improving players’ serve speed compared to traditional model was. Thus, researchers concluded that the new model of resistance-based training can be implemented to increase tennis junior players’ serve speed. Keywords Junior Athletes, Resistance, Strength Training Model, Tennis 1. Introduction Tennis is a popular sport and favored by people from all levels of society without being restricted by age, gender, social status, and some other backgrounds. This branch of sport keeps developing that can be seen by the number of annual tennis tournaments conducted both at national and international levels. Obviously, this phenomenon has impacted on intense competition among the athletes to participate in the tournaments in which, nowadays, professional and semi-professional sport gives slight potential for them to win; and, it becomes an intense pressure for the couches and athletes [1-3]. Therefore, the athletes should be well-prepared and well-trained to compete in every tournament by performing numerous training programs designed to achieve the targets. To develop the athletes’ skill and performance, numerous studies have examined various models of training such as by giving video modelling and imaging training that was empirically proved to have impacts on performance of tennis serve of 9-to 12-year old children [4], a different approach to the design of an effective strength training program in modern tennis conducted by [5] was proved to be effective to enhance basic and specific