Effects of Plyometric-Weight Training and Plyometric Training on Anaerobic Power and Muscle Strength in Male Volley Ball Players

Effects of Plyometric-Weight Training and Plyometric Training on Anaerobic Power and Muscle Strength in Male Volley Ball Players T.N.Suresh 1*, T.S.Veeragoudhaman 2, V.Vijayananth 3, S.Dinesh Kumar 4 1* Student, SRM College of Physiotherapy, SRM University, Kattankulathur, Tamil Nadu, India 2 Vice Principal, SRM College of Physiotherapy, SRM University, Kattankulathur, Tamil Nadu, India 3, 4 Assistant Professor, SRM College of Physiotherapy, SRM University, Kattankulathur, Tamil Nadu, India Corresponding Author: T.N. Suresh Abstract:- Objective: To find out the effects of Plyometric weight training and Plyometric training on anaerobic power and muscle strength in male volley ball players. Study design: Study design: Experimental study, Study type: Comparative study, Sampling method: Simple random sampling, Sample size: 50 subjects (elite volley ball players) Study settings: YMCA, Study duration:6weeks. Intervention: Group A: 25 Volley Ball Players will receive Plyometric and weight training group (who received both Plyometric and weight training). Group B: 25 Volley Ball Players will receive Plyometric training group (who received only Plyometric training) Outcome measures: 1) Vertical height, 2) 50 yard dash, 3) 1RM squat. Results: Statistical analysis was done by using Paired t and independent t test showed significant improvement in improving anaerobic power and muscle strength Conclusion: It is concluded that there is statistically significant improvement in combined Plyomotric and weight training protocol can successfully be incorporated in a fitness training and conditioning program to improve anaerobic power and muscle strength in volley ball players. Key words: Lower limb Plyometrics, Weight Training, Male Volley Ball Players, Vertical Jump height, 50 Yard dash, 1 RM. T I. INTRODUCTION he word plyometric is actually derived from the greek word phelon which means more. Consequently pleiometric means more length and has, through phonetic transcription been changed to plyometric. The effect of plyometric training is highly specific, and its effect on isometric or concentric maximal strength is modest. Stone M et al 1987 (21) concluded that plyometric exercises evoke the elastic properties of the muscle fibers and connective tissue in a way that allows the muscle to store energy during the deceleration phase and release that energy during acceleration period. Plyometric exercises that involve stretching an active muscle prior to its shortening have been shown to enhance performance during the concentric phase of muscular contraction. Weight training is a common type of strength training for developing the strength and size of skeletal muscles fibers. It uses the force of gravity to oppose the force generated by muscle through concentric or eccentric contraction. The basic principles of weight training are essentially identical to those of strength training, and involve a manipulation of the number of repetitions,, exercise types, and weight moved to cause desired increase in strength, endurance, size, and shape. The specific combinations of repetitions,, exercises, and weights depends on the aims of the individual performing the exercise; with fewer repetitions can be performed with heavier weights. Weight training provides the majority of the resistance at the beginning, initiation joint angle of the movement. After this point the overall resistance alters depending on the angle of the joint Volley Ball has become one of the most widely played participant sport in the world. Participation requires expertise in many physical skills and performance on an individual s ability to and on muscle power. Tant et al 1993 (64) suggested that training for volley ball should focus on developing strength and power through fast, explosive movements. Explosive training will enhance the rate of force development of type II fibers through neuromuscular adaptations, which theoretically would reduce movement time during. Weight training is primarily an isotonic form of exercises. In isotonic exercises the force applied to the muscles does not www.rsisinternational.org Page 90

change while in plyometric exercises the length of muscle stretches and contracts rapidly to increase the power output of a muscle. Many studies have proved that plyometric training improves power output and increases explosiveness by training the muscles to do more work in a shorter amount of time in volley ball players. Clutch et al 1983 (20) suggests that weight training increases muscle strength in players. However, the effect of combined training effects of plyometric and weight training is still under research. II. PROCEDURE The study got approval from the ethical committee SRM college of Physiotherapy Subjects were selected based upon inclusion criteria following Male volley ball players, Age group between 19 to 21 years, Off season players, Players who are not being trained in plyometric training and weight training program earlier.and the exclusion criteria Lower extremity or back injury, Recent fracture of the players,acute inflammation,hypermobility of joints and informed consent form was obtained from the subjects and subjects selected convenient sampling. 50 volley ball players were selected and are divided into 2 groups by a simple random sampling. Each group contains of 25 volley ball players. Group A is treated with Plyometric and weight training group (who received both plyometric and weight training. Group B is treated with Plyometric training group (who received only plyometric training) The volley ball players were interested that in case any subject discontinued the training program or if he developed any pain or injury in the legs during the training period then they will be excluded from the study. In this study none of the subjects discontinued the training program and none developed any injury. For both the groups the initial measurements of demographic data were taken. Then pre-test scores were taken for both A&B groups 1 week before the initiation of the training period. Measurement of Vertical Jump Test: Vertical height was measured by using a stand and reach test. The test was completed from a 2-foot standing position without a step into the. The volley ball players were allowed to use their hands as they desired. Three test s were taken, and the highest of these was recorded. This test was selected because it has high validity (0.80) and reliability (0.93) coefficients and because it allows arm movement and a squat motion before the, such as those performed in sports. Measurement of 50 Yard Dash: The 50-yard dash is one of the short-term test for muscular power that indirectly reflects the measure of the volley ball players ability to regenerate ATP during that interval. This test was selected because it has a high correlation coefficient (0.974). In this protocol the volley ball players start 15 yards from the start line and time is measured from a start distance of 50 yards. Measurement of Leg Strength (1 Rm ): To assess strength isotonically a one repetition maximum (1RM) test was performed. Leg strength was assessed by the 1RM (1 repetition maximum) squat. In the squat 1RM test, volley ball players executed the traditional back squat exercise following the National Strength and Conditioning Associatoin guidelines for the execution of this particular test. However, a manual goniometer was used at the knee to standardize the range of motion. The volley ball players started the squat exercise at a 30degree knee flexion, descended to 90degree, and then forcefully returned to the starting position by extending both knees and hips and plantar flexion at the ankles. Volley ball players were alerted when the starting and finishing positions were attained. Pre-testing was conducted in 4 sesssions. The first session included an introduction of the testing protocols to the subjects. The ond session included the measurement of vertical ing performance. In the third session, leg strength was determined by the 1RM squat. During the fourth session, the 50- yard run was measured. There was a 24-hour pause between the testing sessions. The 2 groups were trained for six weeks, 2 days per week. All training sessions were supervised. After 6 weeks of the exercise protocol post test outcome scores were recorded in sessions in the same order 4 days following the completion of the training period. III. TRAINING PROTOCOL GROUP-A PLYOMETRIC AND WEIGHT TRAINING 1 st week:- Depth Split squat Rim 3set X 4 reps with 30 cm. with rest time of 30 between 3 X 4 reps with time of 30 3 set X 4 reps with rest time of 30 2 set X 4 reps with box height of 40 3 boxes used with rest time of 30 4 set X 8 reps, with 30% of 1 RM, 4 set X 8 reps, with 30% of 1 RM,. www.rsisinternational.org Page 91

2 nd week:- Depth Split squat Rim 3 rd week:- Depth Split squat Rim 4 X 8 reps, with 30% of 1 RM 4 set X 8 reps, 30% of 1 RM, 3 set X 6 reps with 40 cm. with rest time of 30 between 3 X 6 reps with time of 30 3 set X 6 reps with rest time of 30 3 set X 4 reps with box height of 30 4 boxes used with rest time of 30. 4 set X 8 reps, with 45% of 1 RM,. 4 set X 8 reps, with 45% of 1 RM,. 4 X 8 reps, with 45% of 1 RM, 4 set X 8 reps, 45% of 1 RM, 3 set X 7 reps with 45 cm with rest time of 30 between 3 X 7 reps with time of 30 3 set X 7 reps with rest time of 30 3 set X 5 reps with box height of 45 3 boxes used with rest time of 30. 4 set X 6 reps, with 60% of 1 RM. 4 set X 6 reps, with 60% of 1 RM,. 4 X 6 reps, with 60% of 1 RM, 4 set X 6 reps, 60% of 1 RM 5 th &6 th week:- Depth 4 set X 6 reps with 55 cm. with rest time of 30 between Split squat 4 X 6 reps with time of 30 Rim 4 set X 6 reps with rest time of 30 PLYOMETRIC TRAINING 1 ST week:- Depth Split squat Rim 2 nd week:- Depth Split squat Rim 3 set X 6 reps with box height of 55 6 boxes used with rest time of 30. 3 set X 6 reps, with 75% of 1 RM, 3 set X 6 reps, with 75% of 1 RM,. 3 X 6 reps, with 75% of 1 RM, 3 set X 6 reps, 75% of 1 RM, GROUP-B 3set X 6 reps with 40 cm with rest time of 30 between 3 X 6 reps with time of 30 3 set X 6 reps with rest time of 30 2 set X 6 reps with box height of 40 4 boxes used with rest time of 30. 3set X 8 reps with 50 cm with rest time of 30 between 3 X 8 reps with time of 30 3 set X 8 reps with rest time of 30 3 set X 5 reps with box height of 50 cm 5 boxes used with rest time of 30. www.rsisinternational.org Page 92

3 rd and 4 th week:- Depth Split squat 4 set X 7 reps with 60 cm. with rest time of 30 between 4 X 7 reps with time of 30 Rim 4 set X 7 reps with rest time of 30 4 set X 5 reps with box height of 60 5 boxes used with rest time of 30. 5 th and 6 th week:- Depth 4 set X 8 reps with 75 cm. with rest time of 30 between Split squat 4 X 8 reps with time of 30 Rim 4 set X 8 reps with rest time of 30 4 set X 6 reps with box height of 75 6 boxes used with rest time of 30. The Plyometric And Weight Training Technique Used: Depth Jump: Split Jump: Rim Jump: A box (variety heights). Stand on the box, toes close to the front edge Step from the box and drop to land on both feet. Try to anticipate the landing and spring up as quickly as you can. Keep the body from settling on the landing, and make the ground contact as short as possible None Spread the feet far apart, front to back, and bend the front leg 90 degrees at the hip and 90 degrees at the knee. Jump up; using arms to help lift, hold the split-squat position. Land in the same position and immediately repeat the A high object such as a basketball goal or crossbar on a football goal post Box To Box Jump:- :- Leg Press: Stand under the high objects with feet shoulder-width apart Jump continuously, reached with alternating hands and trying to reach the object on every. Time on the ground should be minimal, with each being at least as high as the one before. A row of boxes all the same height. Stand in a deep- squat position with feet shoulder- width apart looking down the row of box, landing softly in a squat position Jump to the first box, landing softly in a squat position. Maintaining the squat position, off the box on the order side and immediately onto and off of the following boxes. Keep hands on the hips, or behind the head Rack with barbell. From a rack with barbell upper chest height, position bar high on back of shoulders and grasp barbell to sides. Take bar from rack and stand with shoulder width stance. Descend until thighs are just past parallal to floor. Extend knees and hips until are straight. Return and repet, keep head forward, back straight and feet flat on the floor; equal distribution of weight throughout forefoot and heel.(knees should point same direction as feet throughout movement) Lever seated leg press. Sit on machine with on padded support. Place feet on platform. grasp handles to sides. Push platform away by extending knees and hips. Return and repeat execution. Adjust seat and back support to accommodate near full range of motion without forcing www.rsisinternational.org Page 93

Leg Extension: Leg Flexion: hips to bend at waist. Keep knees pointed same direction as feet. Do not allow heels to raise off of platform and pushing with both heel and forefoot. Lever lag Extension Sit on apparatus with back against padded back support. Place front of lower leg under padded lever. Position the knee articulation at same axis as lever fulcrum. grasp handles to sides for support. Move lever forward by extending knees until leg are straight. Return lever to original position by bending knees. Repeat stabilizers are during heavy resistances To prevent body rising off of seat Lever seated leg curl. Sit on apparatus with back against padded back support. Place back of lower leg on top of padded lever. Secure lap pad against thigh just above knees. Grasp handles on lap support Pull lever to back of thighs by flexing knees. Return lever until knees are straight. Repeat. TABLE-1 COMPARISION BETWEEN PLYOMETRIC WEIGHT TRAINING GROUP AND PLYOMETRIC GROUP Vertical Jump height Plyometric and weight Training Group-A deviatio n Plyometric Group-B deviatio n t-test Signific ance Pre-test 41.505 2.530 41.145 2.494 0.453 0.653 Post-test 49.470 2.482 46.560 2.655 3.580 0.001 TABLE:-2 COMPARISON BETWEEN PLYOMETRIC WEIGHT TRAINING GROUP AND PLYOMETRIC GROUP IN 50 YARD DASH () 50 yard dash Plyometric and Weight training Group-A Plyometric Group-B t-test significance Pre-test 7.897 0.449 7.828 0.571 0.425 0.673 Post test 1 RM Pre test Post test 6.713 0.366 7.036 0.548 2.190 0.035 TABLE:-3 COMPARISION BETWEEN PLYOMETRIC WEIGHT TRAINING GROUP AND PLYOMETRIC GROUP IN 1 RM SQUAT (kg) Plyometric and Weight training Group A Plyometric Group B t-test Significance 80.250 8.346 81.750 9.072 0.544 0.590 111.00 8.207 88.000 9.233 8.326 0.001 IV. RESULTS According to Table: 1 In the post test there is a significance difference between the group (P<0.005) at 0.005 level of significance. Both group shows significant decrease in their post test mean but plyometric weight training group which has the lowest mean is more effective in increasing 50 yard dash According to Table: 2 In the post test there is a significant difference between the group (P<0.001) at 0.001 level of significant. Both groups shows significant increase in their post test mean but plyometric weight training group which has the highest mean is more effective in increasing 1 RM squat. According to Table 3: In the post test there is a significant difference between the group (P<0.001) at 0.001 level of significant. Both groups shows significant increase in their post test mean but plyometric weight training group which has the highest mean is more effective in increasing 1 RM squat. V. DISCUSSION This study is focused on finding out the effects of plyometric and plyometric weight training on anaerobic power and muscle strength in male volley ball players. Jumping is a complex multipoint action that demands not only force production but also a high power output. Plyometric exercises evoke the elastic properties of the muscle fibres and connective tissue in a way that allows the muscle to store energy during the deceleration phase and releases that energy during the acceleration period. Several studies suggested that plyometric consisted of exercises commonly used to enhance explosive power via the stretch shortening cycle (SSC) The stretch component of stretch shortening cycle refers to the eccentric muscle action, whereas the shortening refers to the concentric muscle action. www.rsisinternational.org Page 94

Anderst et al 1994 (4) concluded that weight training has been able to improve vertical performance in most cases by 2-8 cm (or by 5 15%). Ioannis et al 2000 (33) concluded that the combination of plyometric exercises and weight training increased the vertical performance. The statistical result of this study shows that the vertical height was significantly increased in plyometricweight training group than plyometric group in male volley ball players. Bosco et al 1982 (10) showed plyometric training have significant effect in increasing hip and thigh power. This results from enhancing motor units recruitment and improving muscles ability to store kinetic energy within the elastic properties of muscles. Plyometric plus weight training program has a significant effect on increasing hip and thigh power as measured by 50 yard dash. Dynamic nature of this training is highly conductive to enhancing neuromuscular efficiency which in turn allows for excellent transfer of power to other biomechanically similar movements that require a powerful thrust from hips and thighs, such as running. Lyttle et al 1996 concluded that neuromuscular adaptations such a increased inhibition of antagonist muscle as well as better activation and co activation of synergistic muscle may account for the improvement in power output. Rahman Rahimi et al 2006 concluded that weight training increases the muscle strength and plyometric training exploits stretch shortening cycle (SSC); therefore, the strength acquired by the weight training protocols will be used in this cycle (SSC) to produce a more forceful concentric muscle action and increase anaerobic power. The statistical result of this study shows that there is significant improvement in 50 yard dash running in plyometric weight training group than in plyometric group in male volley ball players. One repetition max (1 RM) is the maximal amount of weight that can be lifted only once for a specific exercise, using proper exercises technique. High intensity plyometric exercises can enhance neural stimulation to a level that will significantly increase maximal strength. Because higher threshold motor units (typically type II fibers) are recruited only when high power outputs are demanded, it appears that plyometric exercises are needed to recruit higher threshold motor units, which in turn may contribute to enhanced squat strength. Explosive type of loading used in this study enhanced the excitability of the fast twitch units and therefore primed these units to play a significant role in the performance of maximal strength tests. Leg muscles must be trained to react quickly as possible: plyometric training appears to maximize the coordination of neuromuscular skills and muscle strength. Strength was increased more during the low velocity of the phase of eccentric contraction than during the high velocity of this phase; therefore a weight training program may stimulate greater strength adaptation. The statistical result of this study shows that there is significant increase in 1RM squat in plyometric-weight training group than in plyometric group in male volley ball players. Eccentric muscle contractions have been shown to result in muscle soreness possibly as a result of changes in muscle cell ultra structure. In order to prevent these situations, it is advisable to build up training slowly and to incorporate a weight training program before the plyometric program in order to strengthen the muscles involved. Hence, weight training is used to prepare for plyometric training to reduce the chance of injury, develop a strength base and prepare the musculoskeletal system for high impact forces. VI. CONCLUSION This study concludes combined plyometric and weight training improves anaerobic power and muscle strength by a six week training protocol in athletes more than plyometric training alone. Hence combined plyomotric and weight training protocol can successfully be incorporated in a fitness training and conditioning program to improve anaerobic power and muscle strength in volley ball players. REFERENCES [1]. Adams K, O Shea KL & Climstein M. The effect of squat, plyometric and squat- plyometric training on power production. Journal of Applied Sports Science Research. 1992; 6(1); 36-41. [2]. Adams TM, Worley D & Throgmartin D. An investigation of selected plyometric training exercise on muscular leg strength and power. Track and Field Quarterly Review. 1984; 84(1): 36-40. [3]. 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