This article brings you the second part of the text written by Davor Rokavec, a worthy member of Croatian Beach Handball team and a graduate student of Faculty of Phsycal Education. We hope that this article will reach to some indoor handball coaches.
Influence of the training on the sand on player’s capabilities
Due to the specific characteristics of the sand, numerous scientists and experts in the area of strength and conditioning invested their time in research of the influence of the training on sand on development of player’s capabilities. The results of this research revealed lots of interesting and useful information about influence of sand training on abilities, and this article will focus only on the ones characteristically for handball. Handball is a sport in which strength dominates, a sport that requires fast repetitive usage of force while performing movements as jump shot; block jump, explosive reactions towards the ball or the player, etc. The movements in the indoor, but also in beach handball require agility and reactivity for successful defense, transitions from defense to offence, as well as adjustment to the various “moves” typical for the game. The traditional handball training includes strength development trough Olympics weight lifting, pliometry, strength training; combined with various speed, agility and quickness exercises (S A Q) which include horizontal ladders, cones, jumping rope, etc. The training is usually performed in the closed training place (gym or similar), and the focus is on triple extension and development of strong complex of ankle for fast and explosive moves. However, as previously mentioned, when the training is moved to the sand, ground reaction forces on which the athlete relies in the gym are exchanged with permeability of the surface. The compliance of the sand to the movements of the body makes it difficult for the ankle buoyancy trough the vertical axis and the consequence of that is sinking back in the sand while trying to increase the propulsion. These changes in the ground reaction forces disturb the stability of the entire body, significantly influencing the height of the vertical jump, as well as to decreased ability to change direction and acceleration. Still, these negative influences do not mean that listed capabilities cannot be developed trough sand training. The research has shown that sand training result in same or similar improvements in the increase of the sprinters or jumpers ability as with the training on the solid or grass surface. Moreover, the larger number of muscle fibers are activated, and the good side of that is that usual training with this technique begins to develop by adapting on activation of all this extra fibers, so when the jump is performed on the solid ground as the indoor surfaces not only benefit and effect of pliometric response is recovered, but also the ability of the activation of more muscle fibers. The negative side is that the long-term usage of sand training can decrease the degree of force development, crucial to the height of vertical jump. The reason behind is sinking of the feet in the sand, which leads to longer contraction time, which results in a less explosive upward movement. Therefore, the sand training itself is not a long term solution for increase of the functional results of height of the vertical jump. However, in shorter periods of 4-8 weeks, due to the variability, challenges, as well as the interesting and entertaining character, makes this type of training recommendable to include in a training program. The similar thing happens with the maximal speed. Higher maximal speed is achieved with applying the bigger rely force on the surface, and not trough faster movement of the limbs trough air, i.e. faster leg frequency. During running in the sand, because of sinking of the feet in the sand, the contact time with the surface is significantly longer. Running in the sand not only impairs the dynamic stereotypes in the motoric patterns, which is the goal of contrast training, but also dramatically changes these patterns. The soft surface produces an entirely different stimulus. As the muscle receptors adjust reactive time to the surface, running trough the sand does not stimulate explosive (stretch – shortening) running contact in the phase of maximal speed. This means that the sprints in sand are not appropriate for development of maximal speed, but it should be noted that in fact the maximum speed as the ability is very rarely manifests in sports games, especially in the games such as handball. In beach handball, as well as in indoor handball, the player uses mechanic of triple extension for jumps and short sprints. The mechanism of triple extension is crucial in applying force and propulsion of the body at the greatest possible speed. Understanding the triple extension mechanics on the sand is essential for development of efficient training program for the beach handball. Besides, when designing the program for the beach handball, one has to take in consideration how the body compensates and reacts to the changes in the environment, i.e. surface. Compensation mechanisms for movements in the sand lead to the increase in demands on the hamstrings as the prime extensor of the hip. For players of sand sports, this means that the complete specific training program should include special attention to the training of hip extension, trough function of the hamstrings, including the elements of instability.
Injuries in the sand!
Beach handball, as other sand sports, is relatively young sports game and is practiced mostly during the summer time. In addition, still there are no professional leagues or regular competitions throughout the entire season, according to which one could make conclusions on the injuries specific for this sport. Although some research has been done, the number of samples and data is too small, which makes it impossible to talk of the characteristic injuries of the beach handball. From the available data, personal experience and information gained trough conversations with the medical staff that worked at the beach handball games, a conclusion can be made that the very serious injuries are very rare (the ones that require operative medical care and long recovery), only few severe injuries have been recorded (which were followed by the conservative treatment and shorter absence from the sport field) as luxation of the shoulder or elbow, ankle sprains and similar injuries. Mostly, records show that only some smaller injuries occur as inflammation and tendinitis of an Achilles tendon. Such situations are quite expected, as in the beach handball, different to indoor handball, the physical contacts are minimal, which decreases the possible injuries caused by the outside force. As for the inflammations, of course, the thing is about the characteristics of the surface. The soft surfaces, such as sand, with their softness and permeability overload the tendons and muscles which can cause inflammations and injuries, particularly of the Achilles tendon. Because of the constant adjustment to the surface, each step causes different pressure and forces on the foot, ankle, knee and hip. Beside that, the sand has the tendency of sinking and inclination which also causes a dangerous force, out of the centre of the body on to the feet and ankle, so, with time, running on the uneven surface can result with inflammations and tendinitis of joints and tendons. This means that there is the necessity to adapt the muscle, ligament and tendon system, i.e. the soft tissue to the running in the sand. The sport medicine experts recommend to start with easier running in the shallow sand, even with footwear on, in order to adapt more easily and more successful.
Short overview:
As written above, the «fear» of the beach handball is unjustified, as when one considers all the advantages and disadvantages of this sport, it application, as part of the training program for the indoor handball, is not only possible but also necessary. With the possibility of influence on developing abilites and a low injury risk, beach handball offers numerous other advantages as amusement, friendship, mental relaxation and leisure. In addition, it influences the «timing», movement without the ball, teamwork, perception and many others, for the indoor handball, relevant features. Therefore, when you see the first ray of spring sun, without any doubt and second thoughts grab the ball and together with your friends go in the sand, in order to meet charms and joys of this very interesting sport, in which everyone can participate, regardless of the age or gender.
