RESEARCH ON EXERCISES TO DEVELOP PROFESSIONAL PHYSICAL STRENGTH FOR MALE STUDENTS OF VOVINAM TEAM AT HO CHI MINH CITY UNIVERSITY OF SPORTS, VIETNAM

: On the basis of synthesizing and analyzing the opinions and knowledge of experts, building exercises to develop professional fitness for male Vovinam students in the HCM City University of Sports team. The research has synthesized 27 exercises to develop strength of mind, including 7 supplementary exercises, 5 arm exercises, 9 leg exercises and 6 continuous exercises to be included in the training program in the 2020-2021 school year. The results after 1 year of the experiment showed that the exercises to develop mental strength for male Vovinam students increased.


Introduction
At Ho Chi Minh City University of Sports, Vovinam is a new subject introduced into the intensive curriculum from the 32 regular university courses with both physical education and sports training majors in 2009, but was loved by many students and participated in the practice.The Vovinam team of students from Ho Chi Minh City University of Sports established in 2018 competed in 2 consecutive national student competitions in 2018 and 2019, both of which reached the top.Vovinam competes in a rolling format in 1 day, solving all the competition content from the qualifying round to the final for the highest medal, so it requires physical strength to ensure throughout unlike the martial arts that compete in rounds everyday.That is the reason for choosing the research: "Research on exercises to develop professional physical strength for male students of Vovinam team at Ho Chi Minh City University of Sports".

Materials and method
In the process of researching the topic, the following methods are used: method of synthesis and analysis of documents; survey interview method; methods of pedagogical examination; methods of pedagogical experimental testing; statistical methods.

Select exercises in consultation with experts
Based on the general analysis of documents theory and methods of physical education, consulting the experience of martial arts experts as well as Vovinam, 31 exercises have been screened and selected for professional physical development.These exercises are included in the questionnaires to consult with experts.
Interviewees are researchers, coaches, lecturers with university and postgraduate qualifications, and martial arts masters nationwide.Some subjects have college qualifications or have a coach's degree, but have been training and teaching Vovinam for more than 5 years.The interview results are presented in Table 1.The study conducted Wilcoxon test to ensure agreement between the two interviews.The test results are presented in Table 2 below.

Hypothesis H0:
The mean values of the two populations are the same.From the above results, we see that the observed significance level of the test between the two test interviews is sig.= 0.532 > 0.05 (threshold of statistical significance at P = 0.05).Therefore, we accept the hypothesis H0.Conclusion: according to Wilcoxon test, there is a coincidence and stability between the two interviews.
Research on the convention of choosing exercises that are selected by the majority of votes with more than 75% of the maximum total score, are selected as exercises to develop professional physical strength for male athletes from the Vovinam team at the Ho Chi Minh City University of Sports.Therefore, through a practical survey in the form of an interview, only 27 exercises are eligible to be selected for experimental application (these are bolded in Table 1).

Experimental organization
The plan to apply exercises to develop professional fitness for male athletes of the Vovinam team at the Ho Chi Minh City University of Sport is built based on the timetable for the 2020-2021 school year with 2 phases: Semester 1: from the beginning of November 2020 to December 2020; Semester 2: from the beginning of March 2021 to May 2021.
Before the experiment, a requirement was to conduct grouping so that the results between the two groups were relatively equal.The calculated results show the results before the experiment.
Regarding the method of performing the exercises, because the main feature of improving professional fitness in Vovinam is the high anaerobic capacity of the body, so the exercises must be applied according to the following methods: Approximate exercise intensity, i.e. about 90-95% of the maximum speed at the respective distances used.After a number of repetitions, the absolute speed stat may decrease a bit, but is still considered an approximation of the maximum speed in the thenexisting state of the body.
The time for each repetition can be from 20s to 2 minutes.The up-rest distance decreases gradually after each repetition.For example, between the first and the second, take a break of 5-8 minutes; between the second and third times, take a break of 3-4 minutes; between the third and fourth times, rest for 2-3 minutes.
Through the analysis and synthesis of general principles and bases to build a general physical training program as well as a system of exercises and necessary qualities have been identified, studied, built and put into practice.experience the physical development program according to each stage of the school year.

Evaluating the effectiveness of professional fitness development exercises for male Vovinam students has been applied experimentally 2.3.1. Comparison of professional fitness of the 2 groups before the experiment
The results of the pre-experiment physical fitness test between the control and experimental groups are shown in Table 3: The results of the comparison of pre-experiment professional fitness between the two experimental and control groups showed that in 8/8 tests, all of them were statistically significant (t = 0 -1.37), showing that the difference was not statistically significant.with probability threshold P > 0.05.

Comparison of TLCM of 2 groups after the experiment
Test results are presented in Table 4. Compared with before the experiment, between the experimental group and the control group with similar professional fitness, there was no statistically significant difference in 8/8 tests; after the experiment, the professional fitness of the experimental group was better than the control group and there was a statistically significant difference in 5/8 tests.

Conclusion
Through the research process, 27 exercises have been synthesized, including 7 complementary exercises, 5 arm exercises, 9 leg exercises and 6 consecutive exercises included in the training program during the school year 2020-2021.
The results after 1 year of the experiment showed that the exercises to develop mental strength for male Vovinam students on the Ho Chi Minh City University of Sports in increased, the highest in 30s tests at the probability threshold P>0.05;This is consistent with the law of development of sports performance, because tests with a too short execution time will hardly have a great growth compared to tests performed for a longer time.
From 8/8 tests there was no difference before the experiment, over 2 experimental semesters, there were 5/8 tests with a statistically significant difference at the probability threshold P < 0.05.Creative Commons licensing terms Authors will retain the copyright of their published articles agreeing that a Creative Commons Attribution 4.0 International License (CC BY 4.0) terms will be applied to their work.Under the terms of this license, no permission is required from the author(s) or publisher for members of the community to copy, distribute, transmit or adapt the article content, providing a proper, prominent and unambiguous attribution to the authors in a manner that makes clear that the materials are being reused under permission of a Creative Commons License.Views, opinions and conclusions expressed in this research article are views, opinions and conclusions of the author(s).Open Access Publishing Group and European Journal of Physical Education and Sport Science shall not be responsible or answerable for any loss, damage or liability caused in relation to/arising out of conflict of interests, copyright violations and inappropriate or inaccurate use of any kind content related or integrated on the research work.All the published works are meeting the Open Access Publishing requirements and can be freely accessed, shared, modified, distributed and used in educational, commercial and non-commercial purposes under a Creative Commons attribution 4.0 International License (CC BY 4.0).

Table 1 :
Interview results on a selection of professional fitness development exercises for male athletes of Vovinam team at HCMC University of Sports

Table 2 :
Wilcoxon test results between 2 interviews for professional fitness development exercises

Table 3 :
Physical fitness between experimental control groups before the experiment TN Σ TN Cv% ĐC Σ

Table 4 :
Comparison of professional fitness between experimental and control groups after the experiment TN σTNCv% Course 35 after 01 semester of study, Scientific research topic elementary school, Ho Chi Minh City University of Sport and Sports.Vo Thanh Lam (2015).Physics in Vovinam Technical Principles, Thesis Martial Arts.Pham Thi Kim Lien (2015).Research on building a system of exercises and strength training programs for Vovinam male athletes in Dong Nai province aged 15-16 years old through 6 months of training, thesis.Master of Science in Education, Ho Chi Minh City University of Sports and Sports Tran Hong Quang, Tran Thi Kim Huong, Pham Thi Kim Lien (2016).Vovinam Textbook, Ho Chi Minh City National University Publishing House.