The improvement of these abilities is quite important for a volleyball player, being the muscular strength many times the priority for the young athlete. Several studies have reported significant improvements in vertical jump following resistance training (Baker et al, 1994 ) and (Stone et al, 1981).The purpose of strength training for volleyball is not to build big muscles, but to develop the physical characteristics necessary to improve a player’s performance.

Strength training is very important to volleyball and however, should not be developed independently from other abilities such as agility, speed and endurance.

This program is designed mainly to improve the skill of vertical jump in volleyball for players with moderate to advanced experience.

Needs Analysis

Needs analysis focuses on the fitness needs of both the activity (vertical jump) and the athlete involved in the sport (volleyball).

Sport analysis

Successful participation in volleyball sport requires expertise in many physical skills and performance is often dependent on an individual’s ability to propel themselves into the air during both offensive and defensive manoeuvres. These movements include the jump serve, spike, and block. During the carrying out of a jump serve or a spike, the player jumps high into the air and strikes the ball at the highest point of their jump in an effort to propel the ball rapidly down towards the opposing side of the net.

Defensively, front row players defend against spikes by jumping into the air with their hands raised in an effort to impede the offensive attack. Unlike offensive jumps, defensive jumps are not maximal vertical jump efforts.

There are many factors that are involved in an athlete’s vertical jump and many factors that are involved in improving an athlete’s vertical jump. Vertical jump mainly involves use of the lower limbs. However, the upper limbs play an important role in vertical jump activity. Feltner et al (1999) and Harman et al (1990) concluded that using an arm swing during vertical jumping improved performance over no arm swing.

An upward swing causes a downward force on the trunk which in turn slows the rate of contraction of the leg muscles allowing the muscles to contract at a slower velocity and thus generates more force. The fact that an arm swing is so important to vertical jumping performance, may indicate that there is a technique or skill component to vertical jumping, rather than just leg power (Young, 1995).

Another biomechanical aspect of vertical jump is the bi-lateral deficit. Bi-lateral deficit results in different heights one-leg versus two-leg vertical jump. The maximal height achieved from one-legged jump is approximately 60% of the maximal two-legged height (Challis, 1998). The possible reason for this deficit may be a neuromuscular adaptation. One-leg jump requires a maximal recruitment of muscle fibres due to less muscle mass available.

Furthermore, the height that is achieved by the vertical jump has a direct correlation with the amount of force that is produced by the muscle fibres. This force is created by a phenomenon known as the stretch-shortening cycle of muscle fibres. The stretch-shortening cycle is a natural reaction by muscle fibres to slow the body from fast movements and prevent injury to the individual involved (Kraemer and Newton, 1994). The stretch-shortening cycle involves a counter-movement when a muscle fibre is rapidly stretched creating tension within the muscle. A counter-movement occurs when the muscles are eccentrically stretched, and then rapidly shortened to accelerate the body in the opposite direction and achieve the reverse desirable action.

To accomplish this, the muscles act eccentrically to slow the body and initiate the reverse desirable movement (Kraemer and Newton, 1994). This cycle is critical to vertical jump performance. As the individual flexes the knees to jump, the stretch shortening cycle is activated and the athlete explodes into the jump. Newton et al (1997) claimed that there may be an even more important factor to producing more

forceful contractions. The research that they conducted came to the conclusion that force output did increase as a function of load, but lighter loads also produced more force because of the speed that the muscle was contracting. In terms of muscle fibre type, elite volleyball players typically show muscle fibre percentages of around 52-60% Fast Twitch muscle fibre composition, which compare favourably to samples

from elite level sprinters and jumpers (45-80%FT) (Conlee et al, 1982). A final biomechanical feature of vertical jumps involves the mechanics of the two-joint muscles of the lower limbs. The major muscle groups of the lower extremities involved in vertical jump are the hamstrings, quadriceps and gastrocnemius. All these muscle groups are bi-articulated muscles that cross over multiple joints. The sequence of muscle activation occurs through a proximal to distal pattern (Pandy, 1991). Thus, the gluteus maximus and hamstrings are activated first with a distinct goal of accelerating the trunk upward after countermovement. The activation continues downward through thigh, shank and finally to the toes. Therefore, all of the lower limb muscles must work in order to develop an explosive power.

Energy source

Research has shown that elite volleyball players to rely primarily upon their anaerobic energy system to supply energy demands during a match (Conlee et al, 1982).

However, matches can last up to two and a half hours; therefore some aerobic component must be present as well. Volleyball is 90% anaerobic and 10% aerobic (Baechle et al, 2000). The aerobic energy system may not be relied upon during matches, but it is certainly important during training sessions, rest, and recovery periods. In relation to the specific composition of muscle fibres, it has been suggested that athletes with a well developed anaerobic power capacity will generate more power than athletes with a high aerobic power capacity (Conlee et al, 1982).

Primary sites of injury

The mechanisms and frequencies of injury in volleyball are well documented. The jump-landing sequence is the most common source of injury in volleyball (Briner and Kacmar, 1997). In fact, blocking and spiking are linked with over 70% of volleyball injuries (Watkins and Green, 1992). Ferretti et al., (1992) hypothesized that the high number of jumps and the likelihood of losing balance due to deviations in jumping technique are the primary causes of injury during volleyball. The vast majority (90%) of volleyball injuries occur in the lower extremity with the knee joint being

particularly vulnerable (Gerberich et al, 1987). Knee injuries are of particular importance because they are associated with more lost time from sports participation than other injury sites (Solgård et al, 1995). A well-designed volleyball training program will also help to reduce the incidence and severity of injury in volleyball players. Despite being a non-contact sport, a three study found that volleyball is the eighth most injury prone sport in the age group 14 to 20 years (De Loës ,1995).

Program Design

A well-structured volleyball training program can increase explosive power, vertical jump height, stamina and speed and agility around the court. Skill training alone, such as practising spikes, won't develop the physical traits necessary to play to the athlete's full potential (Gabbett et al, 2006).Volleyball players have exceptional lower body power and perform well in the vertical jump test (Smith et al,1992). Power in the legs is needed to jump explosively off the ground in order to spike, block, set and dive.

This program is designed to maximize the vertical jump for a professional volleyball player who is very interested in increasing his vertical jump to enhance his sport performance for the in-season period. It is a pre-season program which focuses on actual sport specific functions. Squatting, jumping, lateral stepping, hitting and spiking are all common volleyball movements. The pre-season volleyball strength training routine is less intense than the off-season. The goal is to maintain that strength and power, but to perfect sport specific movements.

The subject is a full-time employee therefore he has no plenty of time for training. He also practises volleyball with no real schedule. He devotes his weekend to leisure activities and social commitments, so training must be scheduled during weekdays.

Conveniently, the subject has no prior major sports injury and he was medically cleared fit for resistance training. The subject has good background of resistance training programs and he has been on training course over the past three months. His training included jogging for 30 minutes and some basic general strength exercises. In order to make strength a valuable physiological component, it must be trained in such a way that gains in strength lead to the highest levels of jumping power. This jumping power must then be effectively applied during the game. To achieve this, strength program is structured into three training phases that lead into the competitive phase. This program consists of three phases (mesocycles) derived from a classic periodization model. These three phases are basic strength, explosive strength and reactive strength. Each phase is four weeks in length.

Phase 1

This phase precedes explosive strength and reactive strength training. This is important even for experienced strength-trained athletes as the nature of competitive sport places uneven stresses on the body. The goal here is not to try to necessarily mimic sports movements, but rather just to increase the contractual force producing capabilities of the muscles that are involved in the vertical jump. This phase lasts for 4 weeks and it aims to balance strength between the two sides of the body. It also aims to restore correct balance between the flexors and extensors (such as the hamstrings and quadriceps for example).

Attention will be paid to developing limit strength in the muscles of the quadriceps, glutes, hamstrings and lower back as these are the most important muscle groups for vertical jumping. The muscles of the hip extensors will be given special attention because they are usually the weak links in the large majority of athletes. These muscles are the glutes, hamstrings, and lower back. During this phase, training begins at a low intensity with high volume. It includes sport-specific exercises related to vertical jump as well as some non-specific exercises such as core exercises. Overload progress from 60% to 75% of 1RM. Repetitions per set range from 5 to 10 depending on how intense the exercise is.

Phase 2

The goal of explosive strength exercises is to either perform the movement with more speed, or with more height. For example, try to jump higher while squatting with light to moderate weights. Generally, speed of movement, especially the beginning of the movement, is more important than the load involved when it comes to these exercises.Explosive strength movements focus on developing maximal starting and explosive strength, without much involvement of the reflexive stretch-shortening cycle .They essentially focus on applying max voluntary force as quickly as possible.

In this phase plyometric exercises will be introduced particularly jumps in place and standing jump.

Phase 3

Reactive strength exercises generally consist of jumps. The goal with the reactive strength exercises is to execute the movements with either less time spent on the ground or by jumping higher. These movements allow you to take advantage and build upon the reflexive forces that come from the plyometric effect. They are essential for anyone wanting to jump higher and run faster. This training uses the stretch-shortening cycle (stretch reflex) .The stretching reflex responds to the speed at which muscle/tendon complex is stretched prior to movement. Therefore, the faster and greater the stretch is the greater the corresponding reactive force will be.

Specificity

All exercises included in this program are designed to improve strength, neuromuscular adaptations and recruitment of muscles involved in vertical jump.

Volleyball requires explosive movements with sequential use of muscles in a specific order. Olympic lifts strengthen muscles at a similar velocity and in the same order as needed in volleyball (Cross, 1993). Thus, this program will include use of Olympic lifts (snatch, clean and jerk). Most vertical jumping in volleyball is performed from static standing or from a two-step approach (Black, 1995). However, many upward and lateral movements of the upper limb are needed for blocking and spiking. Upper body and abdominal (trunk) strength has also been shown to be a contributing factor to vertical jump performance (Bobbert et al, 1994).

Strength in the upper body, particularly the arms and shoulders helps to increase the strength throughout the trunk region which creates solid posture to help maximise jumping technique. Therefore, this program includes many exercises of upper body in order to strengthen all muscles involved in vertical jump.Other exercises (bench press, push press and core conditioning) are included in the program although they do not specifically improve vertical jump. These exercises are included to maintain muscular balance and enhance strength base.

While this program is basically designed to improve the vertical jump, it would also be sufficient in developing upper and lower body strength and power. This program also includes some plyometric activities for both upper and lower limbs.Velocity specificity is an important consideration when designing resistance training programs for vertical jump. It indicates that training adaptations (e.g., increased strength/power) are greatest at or near the training velocity (Pereira and Gomes,

2003). However, there exists a conflicting hypothesis that the intention to move a barbell, one’s own body, or any other object explosively is more important than the actual movement velocity in determining velocity-specific responses of the neuromuscular system to resistance training (Behm and Sale, 1993)Plyometric training has been shown to be one of the most effective methods for improving explosive power (Fleck and Kraemer, 2004). A wide variety of athletes can benefit from power training, particularly if it follows or coincides with a strength training program. In order for plyometric training to be at its most effective it should follow a phase of maximal strength training (Baechle et al, 2000). The purpose of plyometrics is to improve the athlete’s capacity to apply more force more rapidly.

Logically then, the greater the athlete’s ability to generate maximal force or strength to begin with, the more of it can be converted into sport-specific power. Weighted vertical jumps are included in this program for its popularity among training specialists and for its proven benefits in many studies. Baker et al. (2001) found that maximal power was achieved during weighted squat jumps with a 48-63% of 1RM squat. Moreover, Wilson et al. (1993) concluded that weighted jumps increased counter-movement and non-counter-movement vertical jump heights more than the traditional resistance training and plyometric.

In the same way, Newton et al (1997) showed that ballistic jump squat training against 30, 60, and 80% 1RM improved vertical jump performance of elite volleyball players significantly more than squat and leg press training with 6RM loads. Subjects in both groups also completed the usual on-court volleyball practice, which involved a large volume of jumping activities. Harris et al. (2000) support this idea by showing the superiority of a combination of heavy- and light-load training to either training method alone in improving a variety of sports performance in football players. Accordingly, athletes may benefit most from resistance training using a range of loads with the intention to move explosively coupled with practicing of the actual sport movement

Equipment and spotting

This program relies mainly on free-weight training exercises including barbell and dumbbells. Other equipment include pulley and plyometric training facilities such as medicine balls, boxes and hurdles .Free weight training has some advantages over machine training such as whole body training and simulation of real sport activities.

However, free weight training requires more balance and coordination. Therefore, spotting is highly required during training with free weights particularly with beginners and young athletes. This program has plenty of free weight exercises performed in different positions and angles and at different velocities therefore, spotting will be carried out for the most of exercises but special attention will be given to the most dangerous exercises such as overhead exercises and Olympic lifts.

Intensity

The intensity of the program starts at a low level and increases gradually throughout the program. 1RM strength was established at the beginning of the program by estimation from a 10RM test-measured value. 1RM is retested every two weeks after the initial test. However, 1RM will be estimated from 1RM-5RM at the beginning of the second mesocycle. Estimating the 1RM from 10RM provides a general guide until the trainee has developed sufficient strength and neural adaptations that would make testing at low RMs safe an effective (Fleck and Kraemer, 2004).

Intensity is adjusted by increasing the amount lifted and using supersetting and compound exercises (several exercises for the same muscle group, or multiple exercises for different muscle groups performed with little or no rest). During the last week (microcycle) of each mesocycle, the intensity and volume are slightly decreased in order to allow time for complete adaptation to take place. Plyometric exercises are introduced according to their intensity level. Low intensity exercises are first introduced followed by moderate and then high intensity exercises.

Training volume

Training volume is generally estimated from the total number of sets and repetitions performed in a single session. A multiple-set (three to six sets) power program incorporated into a strength training program consisting of one to six repetitions in periodized manner is recommended for advanced power training (Fleck and Kraemer, 2004). One meta-analysis (Rhea et al, 2003) concluded that four sets of resistance training produced twice the strength increases of one set. Baker et al (2001) concluded that as training volume increases, power tends to decrease and vice versa. Therefore, in order to maximize power gains in this program, the volume of the training starts at a high level and steadily decreases over time. Resistance training volume is further reduced when introducing plyometric exercises. Volume is adjusted by decreasing the number of repetitions per set or by decreasing the number of sets per session.

Rest and recovery

Adequate rest and recovery are addressed by allowing a full day of rest between each two successive sessions, as well as limiting number of exercises per set. Generally, rest between sets ranges from three to four minutes depending on the number of repetitions performed and intensity of the exercise. For example, a set of 6 repetitions of box jump will need four- minute- rest. When training muscle groups which act together in the same session (i.e. pectorals and deltoids), fatigue may take place. To prevent this problem the muscle groups just trained will be rested - or an unrelated muscle groups such as calf group may be trained - prior to the training of subsequent muscle groups that have similar actions. Plyometric exercises are performed at the beginning of the training session after a thorough warm-up. Doing so, athlete will develop maximal power before muscle become fatigued from resistance training

(Fleck and Kraemer, 2004). The highest volume and intensity exercises are usually performed on Fridays, thus allowing two-day recovery.

Periodization

This program is designed as a pre-season training consisting of three mesocycles, with four microcycles in each mesocycle. Each microcycle is one week long and involves training over three days: Monday, Wednesday and Friday.

Conclusion

This program id designed to improve the vertical jump in a professional volleyball player. The workouts are demanding but simple enough to complete in 40 minutes or less. More importantly, psychological factors have been taken into account. This is the reason for the variation in the program within each cycle. Subject may skip some workouts or be not interested in training because of physical or emotional stress. However, with proper supervision and coaching and compliance to this program, the subject will see not only increases in strength and power, but also improvement in vertical jumping and consequently physical performance.