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Chapter 20: How do athletes train for improved performance? Exam-style Questions page 373 1 Explain how flexibility training is used to improve performance. (8 marks) While the bones that make up a joint will limit the range of movement, many of the other structures that make up a joint (such as muscles, tendons and ligaments) are elastic and improvement in their ability to be stretched can provide improved performance. Improved flexibility allows greater elasticity and a greater range of movement and may reduce injuries. Training for improved flexibility can be performed daily and should be done for at least 15–30 minutes per day. A number of methods can be used to improve flexibility but generally stretches are held for 10–30 seconds and repeated twice. Stretching can be a training session on its own or it can form part of a warm-up or cool-down. The most common and perhaps safest form of stretching is static stretching. This is where the athlete will move slowly and steadily into a position beyond the point of resistance thereby stretching the muscle; for example, reaching for the toes over a straight leg while sitting on the floor to stretch the hamstrings. This position is held for 10–30 seconds and the exercise repeated. Once some degree of improved flexibility is noted further improvement can be gained through proprioceptive neuromuscular facilitation (PNF) stretching. PNF stretching is a form of static stretch and is very effective in improving flexibility. In PNF stretching the muscle is stretched as in static stretching; however, it is then contracted isometrically for 5–6 seconds against a resistance. (The resistance is often provided by a partner. For example, the partner holds the leg of the other person, who is lying on his or her back on the floor, at right angles. The partner assists the stretch and provides resistance.) The muscle is then relaxed and stretched to its maximum. This allows a greater range of movement and improved flexibility. As sports require movement it is important to ensure flexibility training involves some movement. This is achieved through dynamic or range of motion (ROM) stretching. This generally does not greatly improve flexibility in a muscle or around a joint but it is very useful as part of a warm-up routine. By replicating the movements required for a sport or activity the body becomes better prepared for the job ahead. For example, a cricketer will rotate his or her arms in large circles and twist at the hips before he or she begins the bowling action. Increased temperature in the muscles stimulates lengthening and activates nerve response. While not recommended for everyone, athletes who have performed strength training and other forms of flexibility training may use ballistic stretching. Great care should be taken as tearing of muscles can occur due to the build-up of momentum to force the muscle up to and past its normal range of motion. An appropriate warm-up is necessary. For elite athletes this type of stretching will ensure they are well prepared for the rigours of their sport. For example, a footballer will rapidly swing his or her leg simulating the kicking action. PDHPE Application and Inquiry HSC Course ISBN 978 0 19 556610 9 © Oxford University Press Australia 2 Describe how athletes use plyometric training techniques to improve speed and power. (8 marks) Many athletes and trainers use plyometric exercises to increase power and speed and more effectively improve sports performance. Numerous sports require some sort of power action (for example, starting from blocks, jumping, throwing or hopping), thus plyometric training is appropriate for many athletes. However, as many of these exercises are high-risk exercises it is important to recognise that if performed incorrectly or undertaken without preparatory training, plyometrics can increase the risk of injury. The process involved in a plyometric exercise is that the muscle undergoing an eccentric contraction is stretched, followed rapidly by an explosive concentric contraction. The stored energy from the stretch can be utilised immediately to produce a powerful movement. The most important principle to apply to a plyometric training program is that of specificity. For example, a line-out jumper in rugby union is concerned with vertical height, whereas a javelin thrower is aiming for explosive upper-body power to launch the javelin. The exercises undertaken should closely replicate the movements required. The line-out jumper would target exercises specific to the legs, such as depth jumps, hopping and bounding. Depth jumps are performed where the athlete ‘drops’ from a box to the ground (the prestretch), and then immediately jumps up onto another box. Hopping and bounding exercises require the athlete to attempt to stay in the air as long as possible and may also be performed over obstacles, such as hurdles. The javelin thrower would target upper-body exercises, such as push-up claps (where the athlete completes a clap in between each push-up), plyometric push-ups (where the athlete ‘drops’ forward from a kneeling position and attempts to propel the body back to the starting position) and exercises using a medicine ball, such as rapid chest passes. All these exercises typically build speed and strength and increase power. When using plyometric techniques it is important to remember that the focus should be on the quality, not quantity, of work. Appropriate rest periods should ensure that all exercises are completed with maximal intensity. Careful attention should also be given to ensuring the correct technique is used. Exercises are only limited to the imagination and as long the exercise is specific to the activity and involves a ‘pre-stretch’ then the plyometric training techniques will successfully develop speed and power. 3 Evaluate the use of different overload techniques when training to improve strength. (12 marks) When training it is important to constantly challenge the body in order to improve performance. The essential principle here is that of progressive overload. The basis of this principle is that for a training effect to occur the muscle tissue must be worked harder than it is used to; that is, when it is overloaded. As the body adapts to new levels, training programs should continue to be overloaded progressively. This is a very effective method of producing greater maximal efforts over time. Generally, an easy and effective method of progressively overloading muscles to improve strength is to set a weight that can be lifted 10 times over three sets. When more than 10 repetitions can be lifted on the third set, the weight is increased. This is the generally applied method, which produces very good results in developing strength for most athletes. PDHPE Application and Inquiry HSC Course ISBN 978 0 19 556610 9 © Oxford University Press Australia Once an athlete has developed an excellent level of strength, gains from this basic method of overloading will be minimal and then it is necessary to employ some advanced overload techniques in order to continue to gain strength. The advanced techniques will also provide variety, which can be vital for maintaining the athlete’s motivation. There are many recommended and reliable advanced techniques to achieve overload when doing weight training for strength. ‘Blitzing’ uses a range of exercises from different angles for the one muscle during a set. This is highly effective in working all fibres in the muscle as completely as possible and through a full range of motion. For example, the shoulders would be ‘blitzed’ by using a military press, followed by upright rowing, lateral raises and bent-over rowing. Using weights produces an isotonic contraction, which has some limitation as it fails to stress the muscle through its full range of motion. This means that the maximum weight that can be lifted is never more than the weakest point of the muscle. By using ‘forced repetitions’ the athlete can lift greater resistances, thereby effectively gaining greater increases in strength across the full range of motion. The forced repetition is possible through the use of ‘spotters’ who assist the athlete to lift a heavier than normal weight through the weak point. This is a very beneficial form of overloading. ‘Cheating’ also enables an athlete to lift heavier than normal loads but rather than using spotters the athlete uses other muscles to assist the lift. For example, the back muscles are used to help straighten the body from a slight forward lean to gain momentum and assist the completion of a bicep curl. This technique should only be used by advanced lifters and can be a vital overload technique if done appropriately; however, it can lead to injury and develop poor form in lifting in less experienced athletes. ‘Pyramiding’ and ‘reverse pyramiding’ are commonly used overloading techniques that are highly effective and can have some additional endurance benefit for the athlete. Pyramiding involves increasing the load up to an optimal weight while decreasing the number of repetitions. For example, as the athlete performs five sets of an exercise, the resistance is increased for each set but the number of repetitions is lowered. As the muscle fatigues the athlete must work to achieve the prescribed number of repetitions. This can form a vital motivating tool as well as being a highly successful method of developing strength. ‘Reverse pyramiding’ is similar but requires the resistance to be progressively decreased while the number of repetitions is increased. Once again the muscle is worked to fatigue to effectively overload it. ‘Up and down the rack’ combines both forms of pyramiding and while effective in developing strength the time involved to work a specific muscle means that it would be best used to target a muscle for a specific purpose; for example, if the quads were seen to be a weakness. There are other forms of overloading that are also very useful for developing strength. In all cases the effectiveness is achieved through the very high level of intensity, but this may be a problem unless the athlete is well supervised. Regardless of experience, programs should be written in consultation with the coach or trainer, progress should be monitored and, where appropriate, spotters or partners should assist the athlete in completing lifts. 4 Recommend the variety of activities that could be included in a training session in order to stimulate and challenge the athlete. (8 marks) Variety is a very important aspect of training as athletes will be more highly motivated if training sessions are interesting and challenging. Variety can be achieved in a number of ways from using drills, incorporating training aids and having modified games through to setting up specific situations to achieve a specific outcome. PDHPE Application and Inquiry HSC Course ISBN 978 0 19 556610 9 © Oxford University Press Australia Drills practices are important in order to develop skills. Through repetition and observation athletes are able to improve technique and, as they note progression made, they can be stimulated to continue and challenged to make further improvements. While drills can become boring through their repetition there are ways of adding interest. Targets can be used to add to the challenge; for example, hitting a tennis ball against a wall can be made more stimulating by drawing small targets to be hit and more challenging by requiring them to be hit in a certain order. Drills performed in small groups can have an element of competition added. For example, when a ball is dropped that player sits out until only one player is left. Modified or small-sided games are a great way of adding variety as well as being an important and effective component of any session. Games played on small fields with fewer players challenge players through the need to be involved. Changing the rules can keep the activity interesting. For example; the team must complete a set number of passes before scoring or there must be a pass backwards before any forward passes can be thrown. These modified games also allow game-related skills (such as decision-making, reaction and vision skills) to be developed. Changing the format of the contest (for example, having two versus three) adds variety, increases the use of game-related skills and adds to the challenge. Specific outcomes can be applied to modified or small-sided and they may continue for only short periods before resetting in order to have a specific outcome applied to them. These may also develop into larger or actual game-play situations. An example may be the starting of a small game by having a rugby line-out and allowing the play to continue in the forwards for only two phases. Another example could be having the ball turned over in an attacking position in basketball to see how the players respond to the defensive needs. Through a combination of drills practice, modified and small-sided games and games for specific outcomes training sessions can be stimulating and challenging and thereby assist the athletes with improving their performance. 5 Compare the benefits of resistance, weight and isometric training when preparing an athlete for competition. (12 marks) People will always argue about what is the best and most appropriate form of strength training when preparing an athlete for competition. Strength training can take many forms and a variety of muscle contractions can be used. The benefits of different forms of training are best determined by considering what the athlete’s specific performance requirements are and what is available in order to train. Resistance training, using bands or tubing, is cheap and very portable. This makes it an ideal training method, especially when the athlete may need to travel. It is possible to perform all the exercises that can be done with weights and the resistance equipment can be taken to any venue. This means that the athlete can train anywhere at any time and there is no need to have a set area in which to train. The resistance equipment is cheap, meaning that costly gym memberships are not required. PDHPE Application and Inquiry HSC Course ISBN 978 0 19 556610 9 © Oxford University Press Australia Using resistance equipment it is also possible to adapt the exercises to the specific needs of the athlete. As working against gravity is not a feature, multidirectional exercises can be performed. The possibility of more movements allows for greater specificity. For example; a baseball pitcher can replicate the pitching action with resistance supplied by the tubing. Core strength can also be improved due to the need for the body to maintain stability while exercises are performed. It is also possible to develop speed through plyometric-type activity as the bands or tubing allow for rapid, yet smooth movements. Some plyometric exercises can be overloaded easily with the use of the bands or tubing. The application of a lower force early in the movement building to greater resistance at the end allows a smoother movement than with weights and less chance of cheating to complete movements as is the case with weights. The smooth movements are also beneficial for rehabilitation from injury and ‘thera-bands’ are commonly used for this purpose. The possible downside to bands or tubing is their potential to lessen force through use over time and the possibility that they will break. While many of the exercises used with resistance bands are similar to those with weights it is possible to set exercises that can isolate specific muscles. This can be beneficial where there is a need to overcome a particular weakness; for example, in the hamstring muscle of a sprinter or for body builders who require definition. Although not as specific as the resistance bands or tubing, it is possible, through the use of pulleys and cables, to use weights to train for specific actions. For example, a swimmer can use cables while lying on a bench to replicate the pulling action of the arm in freestyle. Weight training may require specific equipment or a gym membership, which can be costly; however, it is possible to assemble an appropriate weight set-up at a reasonable cost—some may be possible to make on your own. While not easily transportable, commonly an appropriate gym set-up will not take up a great deal of room—part of a garage is usually sufficient. In comparison to other forms of training there may be increased muscle soreness due to the eccentric contractions and a less even strength gain due to the biomechanical disadvantage when lifting heavy weights. It is also necessary, for safety reasons, to train with a partner (or spotter) when using heavy weights; although training with a partner may have benefits for motivation. Compared with resistance and weight training, isometric training has far fewer applications to the sports training program. Isometric exercises are not sport specific as the strength is gained through a contraction being held in a static position. There is some benefit to gymnasts where they need to hold a position (for example, the ‘iron cross’ on the Roman rings) and to rugby front rowers, who need to hold their position in the scrum, but as most sports require movement there are better methods of gaining strength. With isometric exercises there are strength and endurance gains in the held position and the exercises are easy to do and can be done anywhere. They are excellent for rehabilitation, especially where a joint injury has occurred and movement may be limited. Due to the static nature of the contraction there may be blood pressure issues, particularly with people who have a history of cardiovascular problems. PDHPE Application and Inquiry HSC Course ISBN 978 0 19 556610 9 © Oxford University Press Australia