The capacity to perform movement over a broad range is known as flexibility, or often mobility, and is significant in training. It is a prerequisite to performing skills with high amplitude and increases the ease with which the athlete can perform fast movements. The success of performing such movements depends on the joint amplitude, or range of motion, which has to be higher than that required by the movement. Thus, there is a need for a flexibility reserve, which the athlete must develop to be on the safe side.
An inadequate development of flexibility, or no flexibility reserve, may lead to various deficiencies, suggested by Pecht (1982) as being the following:
Factors Affecting Flexibility
Flexibility is affected by the form, type, and structure of a joint. Ligaments and tendons also affect flexibility; the more elastic they are, the higher the amplitude of a movement.
The muscles that pass or are adjacent to a joint influence flexibility. In any movement, the contraction of a muscle that acts actively (agonists) is paralleled by the relaxation or stretching of the antagonist muscles. The easier the antagonistic muscles yield, the less energy you spend to defeat their resistance. The capacity of a muscle fiber to stretch increases as a result of flexibility training. Flexibility is often limited regardless of the amount of training invested if the antagonistic muscles are not relaxed, or if there is a lack of coordination between contraction (agonists) and relaxation (antagonists). It is not surprising, therefore, that individuals with poor coordination, or an inability to relax the antagonistic muscles, may have a low rate of flexibility development.
Age and sex affect flexibility to the extent that younger individuals, and girls as opposed to boys, seem to be more flexible. Individuals reach maximum flexibility at 15 or 16 years of age (Mitra and Mogos 1980).
Both general body temperature and specific muscle temperature influence the amplitude of a movement. Wear (1963) found that flexibility increases by 20% following a local warm-up to 115° Fahrenheit (40° Celsius) and decreases by 10 to 20% by cooling the muscle to 65° Fahrenheit (18° Celsius). Similarly, a movement's amplitude increases following a normal warm-up because progressive physical activity intensifies blood irrigation of a muscle, making its fibers more elastic. Consequently, performing stretching exercises before warming up, which seems to be an accepted theory by many North American athletes, is undesirable to say the least. As indicated by the sequence of exercises to follow during warm-up, flexibility exercises come after various types of easy jogging and calisthenics. By the time the athlete performs flexibility movements, the muscle temperature has increased, thus facilitating the muscle fibers to stretch without causing harm. Zatzyorski (1980) investigated the effects on flexibility of no warm-up, warm-up via physical exertion for 20 minutes, and warm-up via hot bath at 40° Celsius for 10 minutes. The results were as expected. The highest degree of flexibility was achieved following normal warm-up and was 21% greater than that resulting from the hot bath and 89% higher than that resulting from no warm-up.
Flexibility varies accordance to the time of day. The highest amplitude of movement seems to be between 10:00 AM. and 11:00 AM., and 4:00 P.M. and 5:00 P.M., and the lowest likely occurs earlier in the morning (figure 13.1). The explanation lies with the continuous biological changes (CNS and muscle tone) that occur during the day (Ozolin 1971).
A lack of adequate muscle strength inhibits the amplitude of various exercises (PechtI1982). Strength, therefore, is an important component of flexibility, and the coach should regard it properly. There are coaches and athletes, however, who think that strength gains limit flexibility or that substantial flexibility gains have a negative influence upon strength. Such theories are based on the fact that the increase in muscle size decreases the joints' flexibility. The capacity of a muscle to stretch cannot, however, affect its ability to perform strength movements.
Strength and flexibility are compatible because the first depends on the cross section of the muscle, and the latter depends on how far a muscle can stretch. These are two different mechanisms and, therefore, do not eliminate each other. Gymnasts who are both strong and flexible are proof of this concept. Remember, however, that an incorrect methodology of developing strength or flexibility may lead to questionable results. Consequently, to avoid any surprise, strength training has to be concurrent with flexibility training.
Fatigue and the emotional state affect flexibility performance significantly. A positive emotional state has positive influence on flexibility compared with depressive feelings. Similarly, flexibility is affected by fatigue (Mitra and Mogos 1980), be it a general state of exhaustion or fatigue accumulated toward the end of a training lesson.
Methods to Develop Flexibility
Use one of the following three groups of methods to develop flexibility.
Before briefly exploring each method, it is important to mention that some contradiction exists regarding which method is most efficient. Many coaches and athletes prefer the static method, fearing that the ballistic method may lead to muscle pull. Although PNF has some limitations in its application, that is, it is applicable only to the hip and shoulder joints, coaches often prefer this method. Several authors (Zatzyorski 1980; Mitra and Mogos 1980; Pecht 1982) however, viewed both the active and the passive methods as equally effective. Similarly, comparative studies (Norman 1973) among the three groups of methods concluded that there is no difference between their effectiveness.
The active method is a technique whereby an individual achieves maximum flexibility of a joint exclusively through muscular activation. This method refers to the extent to which the agonistic muscles flex, as well as the relaxation and yielding to such a force by the antagonistic muscles. When using the static method, the athlete flexes two segments of a limb to the utmost point of flexibility and holds the position for 6 to 12 seconds. The athlete performs the ballistic method through active swings of one segment of a limb that is mobile, against another limb that is still.
The passive method achieves maximum flexibility through the assistance of a partner or by employing a weight. In the first case, a partner holds or presses a limb toward its maximum point of flexibility without the subject's active involvement. This method is applicable for the following joints: ankle, hip, vertebral column, shoulder, and wrist. I recommend using weights (barbells, dumbbells) for improving ankle, knee, and shoulder flexibility. I do not suggest this for the hips or vertebral column, because the weight may exceed the athlete's pain tolerance or may press two segments of a joint to bend beyond their limits, resulting in eventual muscle pulls. In any case, the weight has to be low, carefully applied, and progressively increased. Always do such training under close supervision.
The combined method (PNF) requires the athlete to actively flex the limb to the joint's limit, then execute a maximum isometric contraction against the resistance of a partner. The athlete then lifts the limb voluntarily to a more acute angle beyond previous limits. Once again, the athlete performs the same routine, a strong isometric contraction against the resistance provided by a partner. The athlete may perform the isometric contraction for 4 to 6 seconds, with as many repetitions as he or she can physically tolerate and that are methodologically necessary.
Methodology of Developing Flexibility
The area of training methodology refers to two types of flexibility, general and specific. General flexibility refers to the idea that each athlete has to have a good mobility of all bodily joints, irrespective of specific requirements of a sport or event. Such flexibility is a requirement in training, and it assists the athlete in training tasks and performing substantial unspecific exercises or elements from related sports. On the other hand, specific flexibility implies the quality that is sport or joint specific (Le., specific flexibility of a hurdler differs drastically from that of a butterfly swimmer).
Because developing flexibility is easier at a young age, it has to be part of the training program of each young athlete irrespective of sport specialization. If the athlete achieves a desired degree of flexibility, it does not mean that you should neglect flexibility training. On the contrary, from this point on, flexibility programs must maintain the achieved level.
Incorporate flexibility exercises in the warm-up part of a training lesson. As already indicated, precede flexibility exercises by a general warm-up (jogging and calisthenics) of at least 10 minutes. Relate the selection of exercises and their complexity and difficulty to the athlete's preparation level and the specifics of the sport. The athlete must perform each selected exercise in 3 to 6 sets of 1 to 15 repetitions (or up to a maximum of 60-90 repetitions per lesson). During the rest interval, consider relaxation exercises (shake the group of muscles that have performed or execute a light and short massage). Increase the amplitude of an exercise progressively and carefully throughout the performance. At first, the athlete performs exercises with an amplitude that is not challenging, then progressively increases up to the limits. From this point on, each repetition should aim to reach this superior limit and further it.
For the ballistic method, there is a high variety of exercises, flexions, extensions, and swinging. As suggested by Bompa, Bompa, and Zivic (1981), an athlete can achieve flexibility by employing free exercises, medicine balls, stall bars, and benches. Using medicine balls (i.e., flex the hips while holding the ball with arms extended) increases the leverage of a limb. It also accentuates the momentum, which results in more effective development of flexibility.
For both the static and PNF methods, the athlete tries to position the joints to enhance the sought flexibility. Then the performer statically maintains the position for 6 to 12 seconds (6-10 sets), for a maximum total of 100 to 120 seconds per training lesson for the chosen joints. The athlete can build up such time requirement progressively over 10 to 18 months. Throughout the performance of static flexibility, the performer should relax the antagonistic muscles so they will yield to the pull of the agonists, thus reaching a more acute angle between two limbs.
For the periodization of flexibility, you must achieve most of it during the preparatory phase. Regard the competitive phase as a maintenance period, when the athlete directs the energy and strain on muscle groups toward specific training. In either case, however, flexibility has to be part of an everyday training program and the athlete should perform it toward the end of the warm-up. Athletes attained best results when they trained flexibility twice a day (Ozolin 1971). Even athletes performing four to six training lessons per week still may develop flexibility during early morning training, thus ensuring an adequate flexibility.
FROM: PERIODIZATION: Theory and Methodology of Training--4th edition, By Tudor O. Bompa, PhD
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