Coach_Educational_Article

Coach education article: Speed development in U15 Importance of Speed Professional football is played at a higher tempo than 10 years ago (Williams et al, 1999). Team and player speed have both been implicated in conceding and scoring goals. Outfield football players can cover in excess of 380 miles in a season with a 10th of this at ‘sprinting’ speed (Times 2006). Distances of 10-13km is not uncommon to be covered in a match. Researchers have broken down total distance covered into periods of high and low intensity. They have shown that distance covered, frequency and intensity can be used to determine club and international standard players. It has been shown by time motion analysis that international players undertake 28% and 58% high intensity running and sprinting respectively compared to their professional counterpart players of a lower standard (Bangsbo 2006). The physical demands of sprinting is one element that has been extensively studied. In the past, sports scientists have postulated that those footballers or teams that covered the most distance in a game were more likely to win. The belief of distance covered in a game has largely been discredited and a new theory of repeat sprint ability has emerged. It is now believed that the most critical component in a game (all other factors being equal) is the distance covered at high intensity with those successful teams able to recover from clusters of sprints time and time again. The element of speed is arguably just as important in the junior football player as it is for the professional Speed also plays a crucial component in the youth game. In his study Gissis (2006) looked at 16 year old elite, sub-elite and recreational football players Gissis (2006) reports that speed is one component that separates elite football players from sub-elite/recreational players. . In this study there were no statistical differences between player anthropometric characteristics (age, body mass and height) but there was significant difference in ten-metre sprint times between elite and non-elite/recreational players (Table 1). Table 1: Speed Characteristics of Elite, Sub-elite and Recreational Youth Players Elite (n=18) Sub-elite (n=18) Recreational (n=18) 10 m sprint time (sec) 1.95 2.14 2.21 Janssens et al. (1998) showed that there was a difference between ‘successfully players’ (players selected by clubs playing in the top league) and ‘less successful’ (players not progressing from regional leagues) in terms of performance of 340 metre shuttle running (Williams 2000). Similarly Panif et al. (1997) demonstrated that elite 16-year olds showed improved performance in running than no elite 16-year olds. Figure 1: Optimal Trainability Boys and Girls Optimal time for speed development Grieg 2011 (personal correspondence) describes the typical footballer as a ‘mid ground’ athlete possessing no great athletic attributes, for example although he may cover 10K in a game it is not at an Olympic standard. However all sports people have the potential to increase their speed. Williams and Reilly (2000) argue that with a systematic approach to training there is an increased chance of becoming an aelite player. It would therefore be advantageous to have a program of speed development with the aim of increasing speed in youth players.. The optimal time for speed development for boys appears to be between ages 10-15 years (figure 1). Balyi and Way (2005) report the optimum time to train for speed is when the athlete undergoes a steep acceleration followed by a decellereation in height or Peak Height Velocity (PHV). Andrzejewski (2009) reported that children have a greater number of intermediate fibres (13% compared to an adult which has 2%) and these have the potential to be transformed into fast twitch fibres. The author states that individuality of the football player shold be taken into account. Speed type athletes should not have the exact same program as endurance type athletes. Andrzejewski (2009) provides an example of an individualisation program for speed and endurance type footballers (Table 2). A three series of six repetitions of speed-coordination activities, with duration time of active rest dependent on the players particular motor type and the length of distance covered. Most notably, the time of active rest when compared to the distance covered should be shorter in speed-type players than n endurance-type players (Andrzejewski 2009). Table 2: individualised sprint training session Type of player Running distances covered Rest to work ratio (range) Speed type 10-16 metres 1:20 - 1:32 Endurance type 5-11 metres 1:15 – 1:25 This study demonstrated improvement in speed over 10 and 20 metres. The main reasons for improvement in speed are (a) transforming intermediate fibres into fast twitch fibres, (b) rising phosphagen potential enzymatic activity ie. Creating kinase, (c) improvement in motor unit recruitment, (d) increase in anaerobic power developed during first few steps of a sprint. The optimum sprinting style is composed of an upright posture, high knee drive, arms perpendicular to the body and an increased stride length. This idealistic sprinter style has limited use in the modern game of football. Football consists of clusters of sprints of 6 seconds or less, therefore the modern day footballer predominantly needs stride frequency dominance over stride length. The modern day footballer also requires arm drive that translates across the chest thereby counterbalancing cutting action. There is one exception when ‘sprinting technique’ would be advantageous and that would be in open play when the footballer needed to cover 20-plus metres in a straight line. Although infrequent the long run was witnessed in 2004 Champions League qualifying match between Real Madrid and Wista Krakow. In this game a player sprinted a distance of 65 metres. Components of Speed and Agility Speed and agility are both required by an elite footballer. The main components of speed are: reaction, quickness, acceleration, maximum speed and deceleration table 3.. Greig states that the footballer needs to react to a stimulus as this is more game specific than a standing start sprint. Similary acceleration should be performed from a rolling start rather than a standing one. Maximal speed can be accomplished by playing small sided games whereby players must focus on stride frequency. Grieg (personal correspondence) reports to the lack of training involved in deceleration. Decelleration is just as important as the other components of speed. Table 3: components of speed and agility Speed Agility Reaction Reactive Acceleration Acceleration Deceleration Deceleration Maximum speed Change direction Quickness Coordination The main components of agility are: acceleration, deceleration, change direction, reactive and coordination. Agility develops from age 4 until 13. The two components of changing direction and coordination should also be incorporated into the speed drill. Speed is one of the most important elements of the modern football game, potentially leading to game and player success. Distance covered at high intensity in a game has been used to distinguish between international and recreational players in both adult and youth players. The window of opportunity to develop speed is between 10 – 15 when optimal fast twitch fibres can be formed as well as biochemical changes, motor unit recruitment and anaerobic power is optimised. The sprint football player must have a specific sprint training program with a decreased active rest compared to endurance footballers. Caution must also be shown developing speed in the upright athletic position as the unidirectional 100 metre running style is far from adequate to meet the demands of the multidirectional football game. Agility and speed must be developed in conjunction as stopping distance is rarely worked on. References