An inadequate development of flexibility, or no flexibility reserve, may lead to various deficiencies, suggested by Pechtl (1982) as being:
- learning, or the perfection of various movements is impaired;
- the athlete is injury prone;
- the development of strength, speed and co-ordination are adversely affected;
- the qualitative performance of a movement is limited. (When an individual has a flexibility reserve his/her skills may be performed more rapidly, energetically, easily and expressively.)
Factors Affecting Flexibility
1. 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.
2. The muscles passing or being adjacent to a joint also affect flexibility. In any movement, the contraction of a muscle which acts actively (agonists) is paralleled by the relaxation or stretching of the antagonist muscles. The easier the antagonistic muscles yield, the less energy is spent to defeat their resistance. The capacity of a muscle fibre to stretch increases as a result of flexibility training. However, 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 co-ordination between contraction (agonists) and relaxation (antagonists). Therefore, it is not surprising that individuals with poor co-ordination, or an inability to relax the antagonistic muscles, may have a low rate of flexibility development
3. Age and sex affect flexibility to the extent that younger individuals and girls as opposed to boys, seem to be more flexible. Maximum flexibility appears to be reached at 15-16.years of age (Mitra and Mogos, 1980).
4. 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°F (40°C), and decreases by 10-20% by cooling the muscle to 65o F (18°C). Similarly, the amplitude of a movement increases following a normal warm-up since progressive physical activity intensifies blood irrigation of a muscle, making its fibres more elastic. Consequently, performing stretching exercises prior to 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 be followed during warm-up (refer to chapter on training lesson) flexibility exercises follow after various types of easy jogging and calisthenics. By the time flexibility movements are performed, the muscle temperature has increased, thus facilitating the muscle fibres to stretch without causing eventual harm. Zatzyorski (1980) investigated the effects of no warm-up, warm-up via physical exertion for 20 minutes, and via hot bath at 40°C for 10 minutes, upon flexibility. 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 at all.
5. Flexibility also varies in accordance with the time of day. The highest amplitude of movement seems to be performed between 10:00 and 11:00, and 16:00 and 17:00, while the lowest likely occurs earlier in the morning (figure 115). The explanation seems to lie with the continuous biological changes (CNS and muscle tone) which occur during the day (Ozolin, 1971).
6. A lack of adequate muscle strength also inhibits the amplitude of various exercises (Pechtl, 1982), thus strength is an important component of flexibility, and should be properly regarded by the coach. However, there are coaches and athletes who hold the impression that strength gains limit flexibility, or that substantial gains in flexibility 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, however, can not affect its ability to perform strength movements.
Strength and flexibility are compatible because the first depends on the cross section of the muscle while the latter depends on how far a muscle can be stretched. These are two different mechanisms and therefore not eliminating each other. Gymnasts who are both strong and very flexible are genuine proof of this concept. One must remember, though, that an incorrect methodology of developing strength or flexibility may lead to questionable results. Consequently, in order to avoid any surprise, strength training has to be concurrent with flexibility training.
7. Fatigue and emotional state affect flexibility performance very significantly. A positive emotional state has positive influence upon flexibility as compared to depressive feelings. Similarly, flexibility is also affected by fatigue (Mitra and Mogos, 1980) be it a general state of exhaustion, or fatigue accumulated towards the end of a training lesson.