The performance of the gymnasts on the rings has a specific character,

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1 Sport Science Review, vol. Sport XXIII, Science no. 1-2, Review, 2014, vol. 23 XXIII, - 38 No. 1-2, April 2014 DOI: /ssr Training Methodology to Increase Strength Parameter Based on Improved Neuromuscular Control Case Study Mihaela PUIU 1 The performance of the gymnasts on the rings has a specific character, determined by the alternation of elements in dynamic regime with elements in isometric regime and the endulum movement of the cables to which the two circles are attached (support points). The main parameters that define the specificity of the effort in performing the exercises on the rings are: muscular, ligament and tendon strength, the velocity at which the maximum muscular contraction is produced, muscular and joint resistance, intersegmental coordination, intermuscular coordination in the muscle chains involved and the ability of static and dynamic balance. The purpose of this study was to streamline the existing workout methodologies aimed at developing muscle strength in a short time and with low energy expenditure. To this end we proposed and tested in practice a workout programme with visual feedback in real time, whose main stimulus was aimed at consolidating the neuromotor abilities. The effects produced in the energy mobilization, found at the initial, final and post-experiment test, were significant in terms of immediate increase in the strength parameter and its stabilization in time. Although the research was conducted as a case study, this progress leads us to point out the existence of reserves important improvement of the energy component in the process control and monitoring of the neuromuscular contraction. Keywords: neuromuscular control, real time, strength. 1 National Institute for Sports Research, Bucharest, Romania ISSN: (print) /(online) National Institute for Sport Research Bucharest, Romania 23

2 Training Methodology to Increase Strength Introduction The study on the basis of which this paper is written is a continuation of the research initiated by specialists of the National Institute for Sport Research (INCS) who, based on the observations resulted from research activities and assistance in training given to various groups of athletes, consider that there is a significant reserve to increase muscular strength based on improving the quality of neuromuscular control. In order to streamline existing training methodologies, which are aimed at developing muscular strength in a short time and with low energy expenditure, we proposed and tested in practice a training programme addressing the specific dynamics of the exercises performed on the rings in men s artistic gymnastics. The technology and means used were primarily aimed at increasing the ability to mobilize the energy potential by optimizing the processes of control and transmission of nerve impulses to the neuromuscular structures. Theoretical considerations concerning the specific effort on the rings in men s artistic gymnastics. The value of muscle strength can be estimated by the effect size it produces in interaction with other bodies or one s own body. In the case of men s artistic gymnastics, due to the specific performance on the six apparatus, the manifestation of muscle strength results in moving or maintaining balanced positions at the segmental level and at the whole body level. The specific muscular effort to perform exercises on the rings is characterized by the alternation of exercises in the dynamic regime with exercises in the isometric regime. Parameters defining specific effort in the performance of the rings exercises are: Muscle strength. Ability to apply an optimal level of strength as a result of muscle contraction, both in the dynamic and in the isometric regime, in order to overcome, maintain or give up bodyweight in a controlled manner in the interaction between the body and the two support points, represented by the circles of the rings is the definition of motor skill - strength specific to performing the elements on this apparatus. Consequently, as it is about the condition of handling one s own body between the limits of dynamics allowed by the regulations and the construction of the apparatus, when setting the training objectives and content of the strength training, we always have as an important benchmark own body weight. For performing and maintaining static elements for 2 seconds, as required by the Code of Points, the athlete must reach the performance to have a relative isometric strength level, in terms of arm muscles, of at least 100 % in relation to body weight. 24

3 Sport Science Review, vol. XXIII, No. 1-2, April 2014 Elasticity of muscles, ligaments and tendons. The greater the intensity of muscle contractions and the shortening velocity of muscle fibre, the higher will be the stress on the elements connecting muscles to segments of bone (tendons). Therefore, it is for the benefit of athletes (in order to avoid any trauma to muscle structures), to develop elasticity of muscles and tendons concerned, in parallel with training neuromuscular and energy component to produce strength. Velocity at which maximal muscle contraction is produced. The relationship between the maximum possible strength and the capacity of rapid mobilization of this potential energy is crucial in performing the motor activities at speed and, in particular, in case of performing a quick sequence of elements. A higher level of muscle strength not coupled with the optimal velocity (corresponding to the requirements of the performance techniques) is followed by the inability of athletes to use their actual strength in real time, a characteristic of the specific dynamics of each element. Muscle and joint strength to achieve and to maintain maximal muscle effort. In order to obtain a higher value exercise, the contest regulations require the performance of a certain number of static elements. A specific feature of these elements is achieving balanced body positions in relation to the two points of support, and maintaining these positions for two seconds. Compliance with this statutory requirement is conditional to a great extent on the specific training methodology for performing the exercises on this apparatus, with the ability of the athletes to manifest maximal muscle strength in the isometric regime, at least equal to the body weight, and the ability to maintain this strength for at least two seconds, being critical. Along with the increasing value of maximal muscle strength and the time while this parameter can be maintained, it is important to train joint resistance to sustain such effort. Intersegmental coordination of upper limbs. This requirement is aimed at synchronizing the existing level of energy mobilization between the two arms. Some athletes tendency, especially those who have suffered an injury on one of their arms, to demonstrate significant differences in energy mobilization between the two body segments, is followed by errors in the performance technique and overload on a particular segment, causing enhanced joint and muscle wear and tear and even injuries in the segment. For the simultaneous and synchronous mobilization of energy, of muscle chains in both segments used for the performance, modern technologies for measuring the real-time intensity of the effort is not only a solution, but rather a necessity. 25

4 Training Methodology to Increase Strength Intermuscular coordination in the muscle chains predominantly required to achieve specific effort. Intermuscular coordination, typical of the performance on the rings, is aimed at two aspects: The degree of muscle tightness (local muscle tension) of each muscle in the required muscle chains. It is not enough for a gymnast to have a higher energy potential in each muscle group, but it is more important for him to learn to use this local energy potential in a synchronized manner between all muscle groups belonging to the required muscle chains. The excess strength manifested in certain muscle groups in parallel with an insufficient activation of other groups has as effect decreased ability to manifest strength and difficulties in quickly achieving and sustaining balanced positions. The level of coordination between agonist and antagonist muscles. During specific effort characterized by the alternation of dynamic elements made in movement or slow changes in positions with the effort of maintaining positions, gymnasts require enhanced ability of quick change at neuromuscular level of contraction under shortening-lengthening regime in the agonist-antagonist relationship. Fixing a position is largely determined by the rapidity and degree of synchronization of tension between the agonist and the antagonist muscles. Ability of static and dynamic balance. The construction of the rings and the performance rules established by the Code of Points requires very good training of the ability to control balance. Also, the alternation of static and dynamic elements emphasize the conditions of instability. The elements of balance, called static or strength elements (Vieru, 1997, Baiasu, 1985), can be performed in different positions, the general centre of mass being above, at or below the points of support. Due to the mobility of the cables to which the rings are connected, regardless of the position of the body and the ratio between the general centre of mass and the points of support, we can believe that all the static elements performed in the support position are achieved under conditions of unstable equilibrium. Also, an important factor on which the ability of an athlete depends to manifest his maximal strength is the quality of the coordination of the muscle activity by the nervous system, on which the intramuscular and intermuscular coordination during the contraction depend. Zatsiorski V. believes that the nervous system has three options to produce varying levels of muscle force: Restoration, gradation of total muscle force by adding and extracting active motor units; 26

5 Sport Science Review, vol. XXIII, No. 1-2, April 2014 Frequency encoding, change of frequency of action of motor units; Synchronization, activation of the motor units in a more or less synchronized way. (Zatsiorski, Kramer, 2006, p. 60). Some of the factors that determine the obtaining of performance on the rings are easily objectified and are the main elements handled in training. Another category of factors, such as those in the neuromuscular command and control area are difficult to assess with common tools and means, available in training, are neglected or addressed intuitively and empirically. The premises of research: Methodology of conducting research: The neuromuscular component, a conditional factor of the quality of muscle strength, is a little studied element in the specialized literature on the theory of sports training. Technical difficulties of exploration and analysis of the elements that make up the command and control of the neuromuscular effector system, do not prevent us from turning our attention to this area. We mention that our research is limited only to signalling a number of changes found following neuromuscular control training, without having yet sufficient information to enable us to explain in precise terms the mechanism underlying these effects and the development of standardized training methodology. Purpose of research development of maximal strength in the muscles of upper limbs involved in the adduction movement of arms horizontally, based on the refining of neuromuscular command and control processes. Assumption: 1. Refining of ability of neuromuscular control results in quick and significant increases of muscular strength. 2. Remanence of accumulation of muscle strength obtained by improving the neuromuscular control has a significant duration in time for the competition requirements in the men s artistic gymnastics. 27

6 Training Methodology to Increase Strength Experimental variables: Dependant variable Muscle strength in the upper arms. Independent variable Programme of refining of neuromuscular control. Subjects of research: The experiments was carried out in the form of a case study and the subject of research was an athlete of the Romanian national team in men s artistic gymnastics. The experiment lasted 16 days and contained four stages, structured as follows: Baseline test Neuromuscular control workout. Final test Post-experiment test 7 days from the final test Venue The experiment was carried out at the biomotricity laboratory at the National Institute for Sports Research and Ergosim simulator system was used as a testing and training tool. Overview of the test conditions: Tests were carried out on the condition simulator with the assistance of the software application for strength control in the isometric regime. Introduction of the test tool: The software application for strength control in the isometric regime is an innovation of the specialists at the Laboratory of Sports Performance Technology and Biology of Effort at the National Institute for Sports Research, Bucharest (Bidiugan, Boboc, Solcanu, 2006). With the assistance of this programme, both tests of muscle strength parameter in the isometric regime and training in the isometric regime may be carried out, while maintaining the primary characteristic of the technologies developed based on CASINOR concept (de Hillerin, Shor, Stupineanu, 1983), and namely, the possibility to achieve quick neuromotor corrections by providing real-time information (figure 1). 28

7 Sport Science Review, vol. XXIII, No. 1-2, April 2014 Figure 1. Strength-Time Chart The results provided by this application contain information about the following parameters, which are significant in training professional athletes (according to Bidiugan, R., & colab., 2006): Reaction time; Time required for achieving a given task; Time at which the maximum speed for strength increase was achieved; Value of maximum strength in the isometric regime, simultaneously on two segments; Maximum speed to increase strength; Strength level at which the maximum speed to increase strength was obtained; Average strength level in the isometric regime sustained for a given period of time. The purpose of testing was to assess the relative muscule strength, as well as to evaluate the importance of the changes occurring as a result of the application of the programme proposed by us. Therefore, the average strength expressed in maximal isometric regime for 3 seconds, in the muscles of the upper arms, was measured. Tests were aimed at measuring the athlete s energy potential in three moments of the experiment: before and after the application of the independent variable, as well as at an interval of 7 days from the final testing. 29

8 Training Methodology to Increase Strength The workout position was lying on the back, arms stretched out, and grabbing the rings from top to bottom. The athlete s task was to maintain for 3 seconds the maximum available strength in three different angles of the glenohumeral joint: 135 o, 90 o and 45 o respectively. Training programme: Improving the motor gesture requires interventions aimed at individual development in two directions: the energy component based on development mechanisms and the coordinative component obtained by learning mechanisms. Unlike traditional methods of strength development, which have as key term stress load, the training we proposed was focused on the notion of difficulty of load. This type of training requires the mechanisms of motor learning, aiming finally at the acquisitions produced in terms of energy. The difficulty of the training load means that type of exercise for whose performance the athlete must meet the following conditions: Mobilisation of the potential energy and maintaining it throughout the performance at the level imposed by the training model. Rapid contraction of the muscle groups required in relation to the imposed load, at high speed of transmission of the efferent motor impulse/nervous control. Adjust the speed of contraction and its quality at various speeds of the nervous control. Synchronization of the actions on the two segments (left, right). Description of the training programme The workouts took place at the biometricity laboratory of NISR Bucharest using ERGOSIM simulator. Description of the instrument used for training ERGOSIM simulator is a modular equipment whose main function is to measure strength parameter, and it is designed and made as to ensure control of the acquisition and processing of data, displaying real-time information for 30

9 Sport Science Review, vol. XXIII, No. 1-2, April 2014 the athlete, summary of each exercise, storage of information and their further consultation or processing more thoroughly (de Hillerin, 1996). The workouts performed on the condition simulator, by visual feedback provided in real time (Figure 2 and 3), enable the athletes to become aware of the quality of their own performance and to adjust their motor response in relation to the training load. Any corrections may be made both from one repetition to another and also in real time, while performing a movement. We can consider that the response of a system is in real time as long as this response actually contributes to the decision within the adjustment step which follows the status/ process to which it relates (de Hillerin, 2007). Figure 2. Workout with visual feedback Training programme (Table 1) contained 7 sessions of minutes. Effort was properly adjusted for each workout, starting with 5 sets of 20 reps, then 25 reps and, for most of the programme (5 sessions), sets of 30 reps. The breaks between the sets varied between 1-2 minutes, depending on the stress intensity and the athlete s fatigue. The workout load was set at approximately 15% of the value of the athlete s maximal strength at the baseline test. The workout speed (K) varied between 60% and 40 %, and increased towards the end of the intervention period, along with the stabilization of the neuromuscular control for the type of load imposed. The effort expended by the athlete during workout was characterized by the achievement of the following tasks: The performance of the adduction of the arms horizontally against an imposed resistance, for a certain pre-set length (distance), viewed by the athlete in a graphical form on the monitor. The load level was approximately 15% of the maximal force expressed in isometric regime at the baseline test; 31

10 Training Methodology to Increase Strength Maintaining the pre-set strength level along the entire trajectory of the movement, viewed in real time on a monitor (Figure 3); Synchronization of the actions of the two segments concerning: Time when the movement started; Degree of muscle tension corresponding to the strength level set as a workout load and maintaining it throughout the movement; Simultaneous stopping the arms according to the displayed model. Quick adjustment to various performance speeds, varying by changing the brake coefficient (K). Figure 3. Graphical model viewed and created during workout Previous experience, in which such workout programmes were applied with a load to increase strength based on the improvement of the neuromuscular control, showed that changes occur especially in the area of control, namely of the information processes, with a direct effect on the energy mobilization (Angelescu, Hani, 2007) 32

11 Sport Science Review, vol. XXIII, No. 1-2, April 2014 Table 1 Workout programme Training Processing, presentation and analysis of results obtained during tests performed. The maximum average strength was calculated, cumulated for the left and right arm, in three joint angles, and was related to and expressed as percentage of the athlete s weight (61 Kg). The results obtained following the processing of the data obtained by the subject of research in the three tests are presented in Table 2. Table 2 Test results Test No. of steps Strength level (dan) Brake (%) No. of sets x No. of reps Total volume (no. of reps) % 5X % 5X % 3X X % 5X % 5X % 3X % 2X % 3X % 2X30 60 Total Reps 965 Average strength (dan) Strength level, right-left, in different angles in the glenohumeral joint 45 o 90 o 135 o Relative strength (%) Average strength (dan) Relative strength (%) Average strength (dan) Relative strength (%) Baseline Final Post-Final

12 Training Methodology to Increase Strength Analysis of results obtained As shown in table 2 and chart 4, the progress made by the subjects of research at the final test presents different values in the three positions (angles in the glenohumeral joint). The highest increase of strength was obtained in the 90 0 angle at dan from the baseline, at 60.9 dan at the final testing, namely an increase of 15.88% from the baseline. Although, as regards the 45 0 angle, the baseline values were the highest, dan as compared to for 90 o angle and 48.88daN for 135 o angle, the progress achieved is small, 2.56%, similar to that obtained in the 135 o angle, and 2.14 dan respectively. We notice an interesting evolution of the strength parameter in the next 7 days from the completion of the workout session. We mention that during this time, the athlete did not participate in any training programme. The charts 5 and 6 indicate a significant strength increase in the positions of 90 o and 135 o angles, namely 21.37% against the baseline, as compared to 15.88% obtained at the completion of the training programme for 90 o and 13.36% of the baseline value as compared to 2.14% at the final test in the position at 135 o angle. We also notice that in the 45 o angle, where the athlete has the highest strength level as compared to the other two positions, at the post-final test (2.04% of the baseline) he recorded a slight regress as compared to the final test (2.56% as compared to the baseline). Chart 1. Results expressed in dan obtained in the three tests in different joint angles 34

13 Sport Science Review, vol. XXIII, No. 1-2, April 2014 Chart 5. Values of relative strength in three joint angles at the three tests Chart 6. Progress made at the final test and 7 days from the experiment, expressed in percentage, as compared to the baseline 35

14 Training Methodology to Increase Strength Conclusions Although research has been conducted on one subject, the progress made by him has determined us to point out and emphasize the importance of workout aimed at improving coordination between the nerve command and the motor response in order to increase the mobilization ability of the energy potential. Likewise, another significant effect observed is the continuous evolution of the value of strength parameter for seven days from the completion of the workout programme. Considering that the main training stimulus was oriented towards consolidating the neuromotor skills, and the effects were significant both in the immediate increase in the strength parameter, and in its stabilization in time, we believe there are some reserves aimed at the improvement of the energy component in the processes of command and control of the muscle contraction. Although our experiences of using neuromuscular control workout, with real time visual feedback, signalled the existence of significant changes in the relationship between neuronal controls - energy mobilization, there are currently few possibilities to substantiate a theory to explain and to outline individual training methodologies. We can, however, emphasize the importance of using workout technologies developed based on the principles of CASINOR concept in professional sports. According to this concept The human subject is placed in a feedback loop with a device capable of following the parameters of the movements of the human subject and provide him with quality feedback on the movement performed. (Văleanu, 2013, p.84). The training of the control and adjustment segment of the muscle contraction involved in achieving specific movements, under voluntary conditions, with a much smaller load than the workout load (for instance, own body weight in gymnastics) transfers the workout load from the area of adaptive phenomena to the area of learning and conscious control of the neuromotor response. Hence, another important aspect of using such equipment results, especially noticeable in high-performance athletes whose muscle-joint wear and tear is accentuated due to the loads imposed by specific effort. We further present a few principles on the basis of which we carried out the workout programme for this experiment: Work load (force) between 10 and 15% of the maximum strength expressed. 36

15 Sport Science Review, vol. XXIII, No. 1-2, April 2014 Optimal speed (K) requiring effort from the athlete to improve his neuromuscular skills. Increasing workout speed (K) during the programme depending on the stabilization of control on effort loads. Total number of exercises/workout Necessity to individualize the training, mainly depending on the ability of each athlete to respond properly (maintaining the workout model) at various load speeds. Such methodology cannot be mistaken for a general recipe, valid for all athletes. Each athlete has his own evolution concerning the neuromotor adjustment to the imposed stress. References Băiaşu, Gh., et al. (1985).Gimnastică [Gymnastics]. Bucureşti: Ed. Sport-turism. Bidiugan, R., Boboc, D., & Solcanu, M. (2006). Aplicaţie soft pentru testarea în regim de izometrie a sportivilor de performanţă [Software Application for Testing Professional Athletes in the Isometric Regime]. Conferinţă ştiinţifică internaţională [International Scientific Conference]. Bucureşti: CSSR Cod de punctaj - Gimnastică Artistică Masculină. [Code of Points Men s Artistic Gymanstics]. (2013). Hani, A., & Angelescu, N. (2007). Modificări ale parametrilor de forţă ca efecte ale antrenamentelor de control neuromuscular [Changes in Strength Parameters as Effects of Neuromoscular Control Training]. Conferinţă ştiinţifică internaţională, [International Scientific Conference]. Bucureşti: CSSR. de Hillerin, P. J., Schor, V., & Stupineanu, I. (1996). Ergosim marcă, ansamblu de concepte sau aparat de pregătire? [Ergosim a Trademark, Set of Concepts or Training Device?]. Revista Ştiinţa Sportului, 3, Bucureşti: CSSR de Hillerin, P. J. (2007). Locul şi rolul informaţiei în dezvoltarea potenţialului de performanţă al sportivilor de elită [Place and Role of Information in the Development of the Performance Potential of Elite Athletes]. Revista Ştiinţa Sportului, 2(57), Bucureşti. 37

16 Training Methodology to Increase Strength Vieru, N. (1997). Manual de gimnastică sportivă [Manual of Sports Gymnastics]. Bucureşti: Ed. Driada. Văleanu, V. M. (2013). Soluţii de achiziţie şi transmitere de date de performanţă umană cu aplicaţii în sisteme pentru protecţia sănătăţii persoanei prin tele-asistenţă [Acquisition and Data Transmission Solutions of Human Performance with Application in Human Health Protection Systems via Tele-Assistance]. Teză de doctorat [PhD Thesis]. Bucureşti. Zatsiorski V. M., & Kramer, W. L. (2006). Science and Practice of Strength Training. (2nd Ed.). Human Kinetics. Mihaela PUIU, researcher within the National Institute for Sport Research (Bucharest, Romania). She graduated the Faculty of Physical Education and Sport of the National University of Physical Education and Sport (Bucharest) in 1996 and has a doctor degree in the same field (2009). Her doctoral thesis is entitled The role of sensory processes in educating the coordinative capacity in children with visual impairments. Within the National Research Institute for Sport, her primary tasks is to cover the provision of scientific advice and assistance on issues dealing with sport training methodology for National and Olympic teams. Under the scientific support contracts concluded between INCS and the Romanian Gymnastics Federation, during , Mrs. Puiu is in charge with provision of biomotor assistance to the members of the national team of male artistic gymnasts, which consists in developing and applying methodologies for the use of conditions in the evaluation and training of the neuromotor abilities that are either specific or nonspecific to male gymnastics. In the period she has published a number of 7 scientific articles on the enhancement and improvement of human neuromuscular behavior regulation and self-regulation capacity. Corresponding address: Mihaela Solcanu National Institute for Sport Research 41A, Basarabia Bvd., District Bucharest Romania mihaela.solcanu@sportscience.ro 38