Physiological DemandsGaelic Football is well known to be a very physical sports, to be a good Gaelic Football player, there are several basic skills that the players need to master, such as high catching, long distance kicking for accuracy, passing and moving the ball downfield, solo running by kicking the ball to oneself and collecting it before it bounces, and blocking an opponent’s kick or hand pass (Reilly et al, 2000).The physiological demands of a Gaelic Football player are governed by the irregular changes of pace and anaerobic efforts that are superimposed on a backdrop of sustained light to moderate aerobic activity. Reilly at al., 2000, split the physiological demands into 3 categories: Characteristics of Players, Work rates during matches, and Physiological response to match play.Characteristic of PlayersGaelic Football players have a similar body characteristic with Australian Rules Football players, but smaller than Rugby player, and bigger than soccer player (Douge, 1988). According to Watson, 1977, in his study of the physical working capacity of Gaelic Football players, Watson reported that to be a successful Gaelic Football, the players need to be tall and heavy at the same time. Watson reported that the players have the average figures of 13-14% Body Fat with high muscle mass of 60.7%, compared to the normal population that only has 40% of muscle mass (Martin et al, 1990). This anthropometry characteristic is different between playing position. Goalkeepers were taller and heavier than defenders and forwards. Midfielders in this study were taller and heavier than defenders and forwards (McIntyre et al, 2005).Gaelic Football players need to have a good Aerobic Power to be able to compete in high physical 70 minutes match. Maximum oxygen uptake (Vo2max) is the indicator of aerobic power (Reilly et al, 2000), a high VO2max contributes to performance in Gaelic Football (Watson, 1977). The average VO2max in Gaelic Football player is 54-58 ml/kg/min (Young et al, 1994), which is lower compared to elite soccer players who have the average of 60 ml/kg/min of VO2max (Bangsbo, 1994).Although aerobic fitness is important to compete full 70 minutes for Gaelic Football players, speed over short distances to tackle and to get away from the opponent is also a determinant of performance (Reilly et al, 2000). Muscle strength and power for tackling, kicking the ball, jumping to win the ball or deflect the ball from the opponent are categorised as anaerobic fitness. Gaelic footballers need to have a strong upper body and lower body which required during resisting and instigating physical challenges, both in retention and winning possession. Gaelic football is a high-intensity sport, McIntyre et al, 2005 using time-motion analysis has shown that 16% of the match is high-intensity type of activities.Work Rates During MatchesExercise intensity during football matches can be represented as distance covered in a game. The average total distance covered in Gaelic Football game is estimated to be 8-9km per game (Keane et al, 1993). The smaller distance covered by the player is likely because of muscle glycogen depletion stores, where have been reported by Saltin, 1973, that at the end of competitive games, low concentration of muscle glycogen in vastus lateralis occurred. Reilly et al, 2000, has reported that lower fitness levels of Gaelic Footballer may not be able to maintain a relatively high work during the match, resulting in fatigue and decline the work rate. Reilly et al believe that the decline work rate is because reduced in muscle glycogen stores and altered blood glucose concentration.Physiological Response to Match PlayHeart rate response to exercise shows a measurement of physiological strain. Mean heart rate for a full game has been used as a measure of exercise intensity (Bangsbo, 1994). Florida-James, 1995 has reported that the average heart rate during the game is 86% of players’ heart rate max, which is bigger than 81% for soccer players. Gaelic footballers also have been reported to use 72% of their maximal oxygen uptake. Those numbers have shown that in Gaelic Football, whether it is an inter-county or club standard, it represents strenuous exercise (Reilly, 2000).The high number of heart rate during the match indicates largely submaximal intensities of movement, which use aerobic metabolism as predominance energy use. The contribution ofanaerobic glycolysis to metabolism is reflected in elevation in lactate production within the muscle and delayed appearance in the blood (Florida-James, 1995).Biomechanical DemandsBiomechanics of sports provide definition and understanding of skills that performed in the sports. There is a wide range of skills which form the foundation of Gaelic Football, which players have to master in order to compete at the highest level. Those skills such as, kicking, jumping, passing, tackling, and sprinting have been the subject of biomechanical analysis (Reilly, 1966).There are several biomechanical factors affecting human strength, such as Neural Control, Muscle Cross-Sectional Area, Arrangement of Muscle Fibres, Muscle Length, Joint Angle, Contractile Velocity, and Joint Angular Velocity. All of these factors have a contribution to the basic football skills.Joint Angular VelocitiesAngular velocity, also called rotational velocity, is a quantitative expression of the amount of rotation that a spinning object undergoes per unit time. It is directly related to velocity produced. In Gaelic Football, Angular Velocities is used in biomechanics perspective to quantify the kicking movement and power by the players. It has been shown that the most successful goalscorers are those players who are able to kick the ball better, and especially be able to score with both feet (Starosta, 1988).During the kicking movement, the leg functions as an open kinetic chain. Kicking leg moves backward, with hip extending up to 29°. The hip is slowly adducted and externally rotated (Levanon et al, 1998). The knee flexes at 745-860 deg/sec and externally rotates (Nunome et al, 2002). The ankle is plantarflexed at 10°, adducted 20°, and slightly pronated (Levanon et al, 1998), reaching maximum plantarflexion velocities of 860 deg/sec (Nunome et al, 2002).The angular acceleration of the link segment system of the kicking leg depends on energy transfer between segments, the muscle moments producing the rotation of the thigh, shank, and foot and the rotational inertia of these leg segments (Dörge et al, 2002). The velocity of the foot is a function of linear velocity of knee and angular velocity of the shank. Luhtanen, 1988, has shown in his study that angular velocity of the shank is very important, where it is a measure of a successful kick. The higher the foot speeds, the greater amount ofwork on the shank originates, which result in a higher velocity of the foot when kicking the ball (Dörge et al, 2001).Cross-Sectional AreaCross-Sectional Area is the area of crossing between actin and myosin in the muscle, it affects the force produced by muscle. Strength training which results in muscle hypertrophy has been described as an overall increase of cross-sectional area (Narici et al, 1989). As muscle get bigger from muscle hypertrophy, the angle-force relation of muscle group will be changed and adjusted to make an optimum angle at which maximum force is generated (Jones et al, 1987).As a Gaelic Footballer, the players have to do strength training in order to increase their muscle force. It has been shown that strength training leads to an increase in force production per unit cross-sectional area of the muscle, due to increase in neural drive (Moritani et al, 1979). The other factor will be the increase in muscle-specific tension due to the denser packing of muscle filaments (Jones et al, 1987). The denser the muscle, it would increase the angle of pennation of muscle fibres (Gollinck et al, 1981).Naricis et al, 1996, in their study about anatomical human quadriceps after strength training for 6 months has shown the increase of parallel cross-sectional area, indicating a constant contribution of hypertrophy towards the increase in strength. The increasing number of the sectional area leads to improvement in coordination, reduced antagonist co-activation and an increase in force, and possibly to the greater density of contractile tissue.The cross-sectional area also being a factor in Rate Force Development. Rate of Force Development is an ‘explosive’ muscle strength or the ability of the muscle to be able to rapidly develop muscular force. Resistance training has been reported to increase Rate of Force Development (Aagaard et al, 2002). Rate of Force Development is applied during jumping in Gaelic Football, where there is a time needed to build up the force, in order for the players to jump high and it takes about 300ms is needed to reach at maximum muscular force (Narici et al, 1996)Joint AngleJoint angle is related to torque-angle relationship, which has a relationship with sarcomere length. Different angle of a joint will result in different torque produced (Onishi et al, 2002), and motor-unit activation (Libet et al, 1959). Therefore, it was considered that the relationship between torque and angle is influenced not only by sarcomere length and moment of arm but also muscle activation that performed with maximum effort (Onishi, 2002).To produce a great amount of force, athletes need to stretch or put their muscle and joint at the perfect angle. During hand pass, bring the arms back to -45° angle will be very effective to create big force. Onishi et al, 2002, using the EMG activity has shown that the peak EMG or the greatest amount of force between knee flexion angles of 90-105° when kicking the ball.