Cardiff School of Sport DISSERTATION ASSESSMENT PROFORMA: Empirical 1

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1 Cardiff School of Sport DISSERTATION ASSESSMENT PROFORMA: Empirical 1 Student name: Programme: Lewis-Jon Hudd Student ID: SCRAM Dissertation title: Supervisor: Traditional Strength Training vs. Cluster Training in Academy Rugby Union Players Robert Meyers Comments Section Title and Abstract (5%) Title to include: A concise indication of the research question/problem. Abstract to include: A concise summary of the empirical study undertaken. Introduction and literature review (25%) To include: outline of context (theoretical/conceptual/applied) for the question; analysis of findings of previous related research including gaps in the literature and relevant contributions; logical flow to, and clear presentation of the research problem/ question; an indication of any research expectations, (i.e., hypotheses if applicable). Methods and Research Design (15%) To include: details of the research design and justification for the methods applied; participant details; comprehensive replicable protocol. Results and Analysis (15%) 2 To include: description and justification of data treatment/ data analysis procedures; appropriate presentation of analysed data within text and in tables or figures; description of critical findings. Discussion and Conclusions (30%) 2 To include: collation of information and ideas and evaluation of those ideas relative to the extant literature/concept/theory and research question/problem; adoption of a personal position on the study by linking and combining different elements of the data reported; discussion of the real-life impact of your research findings for coaches and/or practitioners (i.e. practical implications); discussion of the limitations and a critical reflection of the approach/process adopted; and indication of potential improvements and future developments building on the study; and a conclusion which summarises the relationship between the research question and the major findings. Presentation (10%) To include: academic writing style; depth, scope and accuracy of referencing in the text and final reference list; clarity in organisation, formatting and visual presentation 1 This form should be used for both quantitative and qualitative dissertations. The descriptors associated with both quantitative and qualitative dissertations should be referred to by both students and markers. 2 There is scope within qualitative dissertations for the RESULTS and DISCUSSION sections to be presented as a combined section followed. The mark distribution and criteria across these two sections should be aggregated in those circumstances.

2 CARDIFF METROPOLITAN UNIVERSITY Prifysgol Fetropolitan Caerdydd CARDIFF SCHOOL OF SPORT DEGREE OF BACHELOR OF SCIENCE (HONOURS) SPORT CONDITIONING, REHABILITATION AND MASSAGE TRADITIONAL STRENGTH TRAINING VS. CLUSTER TRAINING IN ACADEMY RUGBY UNION PLAYERS (Dissertation submitted under the area of SCRAM) Lewis-Jon Hudd st

3 Cardiff Metropolitan University Prifysgol Fetropolitan Caerdydd Certificate of student By submitting this document, I certify that the whole of this work is the result of my individual effort, that all quotations from books and journals have been acknowledged, and that the word count given below is a true and accurate record of the words contained (omitting contents pages, acknowledgements, indices, tables, figures, plates, reference list and appendices). I further certify that the work was either deemed to not need ethical approval or was entirely within the ethical approval granted under the code entered below. Ethical approval code: 14/5/149U Word count: 8,027 Name: Lewis-Jon Hudd Date: 15/03/2015 Certificate of Dissertation Supervisor responsible I am satisfied that this work is the result of the student s own effort and was either deemed to not need ethical approval (as indicated by 'exempt' above) or was entirely within the ethical approval granted under the code entered above. I have received dissertation verification information from this student Name: Date: Notes: The University owns the right to reprint all or part of this document.

4 TRADITIONAL STRENGTH TRAINING VS. CLUSTER TRAINING IN ACADEMY RUGBY UNION PLAYERS

5 TABLE OF CONTENTS Acknowledgements 5 Abstract 5 Page CHAPTER ONE 1.0 Introduction 1 CHAPTER TWO 2.0 Literature Review Strength Training Cluster Training Testing Approaches 10 CHAPTER THREE 3.0 Methods Participants Ethical Approval Protocol Testing Procedures Data Analysis 16 CHAPTER FOUR 4.0 Results Anthropometrics Strength 1RM Squat Slow Speed Strength CMJ Fast Speed Strength Drop Jump, Ground Contact Time and RSI 20

6 CHAPTER FIVE 5.0 Discussion Anthropometrics Strength Slow Speed Strength Fast Speed Strength Limitations 25 CHAPTER SIX 6.0 Conclusion 27 REFERENCES APPENDICES Appendix A. Pre and Post Testing Data Sheet Appendix B. Example of Traditional Strength Programme Appendix C. Example of Cluster Strength Programme

7 LIST OF TABLES Table Page 1. Standardised RAMP Warm up Protocol General Characteristics of Participants Drop Jump Height, Ground Contact Time and RSI Scores 20 LIST OF FIGURES Figure Page 1. Force-Velocity Relationship and Aspects Involved 5 2. Mean 1RM Squat Scores from Pre and Post Testing for Both Groups Mean CMJ Scores from Pre and Post Testing for Both Groups 19

8 ACKNOWLEDGEMENTS I would like to thank Rhodri Williams, James Chapron, Robert Sidoli, Matthew Jones and the participants for their support and participation provided outside of the university. I would also like to thank my tutor, Robert Meyers for his support throughout the course of the study. ABSTRACT Objectives: To investigate the differences and similarities between traditional strength training and cluster or inter-repetition rest training in academy rugby union players and its effects on the force velocity curve, to determine which training method is better for development of each independent quality. Methods: A total of 22 collegiate academy rugby union players participated in a 4 week training intervention, where each player was randomly assigned into a group, traditional or cluster. Players underwent anthropometric measurements of height and weight and measurements of strength, power and speed-strength before and after the 4 week training intervention. Each player would follow a designed programme, where training loads progressively increased week by week. Training loads were calculated from a 1 repetition max (RM) at pre-testing. Each session would be supervised by a qualified strength and conditioning coach, where a RAMP warm up would be taken prior to training. After each gym and field session each player would give an RPE (Rate of Perceived Exertion) score out of 10, to ensure training intensity and volume would be matched across both training groups and due to the study taking place in-season. Results: Throughout the four week training intervention both training groups, cluster and traditional, saw significant increases in body mass, 1RM squat, Countermovement jump (CMJ) and Drop jump scores (P < 0.01). There was a significant difference in CMJ between the cluster group and the traditional group; however the cluster group saw lower baseline scores in 1RM squat and CMJ compared to the traditional group. Conclusion: These findings indicate that both methods, traditional strength and cluster training, are both suitable methods for developing strength qualities whereas cluster training proving to be ideal for developing speed-strength qualities. i

9 CHAPTER ONE INTRODUCTION

10 1.0 Introduction Periodization is known as the portions or divisions of time which divide into smaller, easy to manage phases of training. This process is considered when designing training programmes across a rugby season and is appropriate for athletes that require a physiological stimulus in order to generate improvements (Bompa and Haff, 2009). Rugby union is a physical demanding sport which challenges players through bouts of high intensity activities such as running, tackling, jumping, kicking and passing (McLean, 1992). Research into rugby has found that players at the professional level are very much dependent on high levels of strength and power for optimal sporting and gym performance compared to collegiate level (Baker and Nance, 1999b; Baker, 2001). Resistance training has been proven to have sporting effects across the board from youth level and up to adulthood and to the point of professional sport at all age grades (Haff, 2012). Resistance training has been proven to benefit youth and adolescents through injury prevention. Through professional guidance and qualified supervision, resistance training can enhance bone-mineral density and improve skeletal health which can ultimately reduce injury risk within young athletes. (Faigenbaum and Myer, 2009; Lloyd et al, 2014). From injury prevention to performance enhancement, resistance training will have some effect to athletes and the strength and conditioning coaches application. Strength should be considered within planning and in any other training stimulus as its relationship with other elements such as power, speed-strength and speed. It is also believed that good levels of strength can allow athletes to further develop in the ability to maintain positional elements and power output, where stronger athletes tend to express higher levels of strength power output at faster rates that athletes who are weak (Haff and Nimphius, 2012; Cormie et al, 2010). As a result younger and weaker athletes do not possess high strength levels for greater power outputs, so by increasing strength qualities it can result in an increase in power output. Varying factors on the force velocity curve and overall performance capacity is suitable for younger athletes to progress from strength foundation into more maximal strength, power and general speed exercises (Häkkinen and Komi, 1985). This study will look at resistance training in further depth with two interventions; traditional training and cluster training and see the differences and similarities between 1

11 each training intervention on the force velocity curve in collegiate academy rugby union players. Leading on from Haff and Nimphius (2012), Cormie et al (2010) and Häkkenin and Komi (1985) traditional training programme studies previously have been inadequate due to having no progressions in the training load, volume and duration. As a result strength increases were minimal if any (Vrijens, 1978). Although research has suggested that loads, volumes and duration of sessions are similar to Olympic lifters in competition and can be ideal in increasing strength levels in children and youth. Strength gains also seem to be more linked with training intensity as high-intensity programmes have shown to increase strength within six weeks or less (Mersch and Stoboy, 1989; Nielsen et al, 1980). This research shows that youth athletes have a high anaerobic threshold and for adaptations to occur all training stimuli need to be sub maximal to challenge the athlete. Deeper research into altering a training stimulus, cluster or inter-repetition rest training can be used by set and repetition manipulation. This method for cluster training is to improve force, velocity and power profile through a training set (Haff, 2012). An assumption can be made that increased rest in between repetitions then force, velocity and power output can be maintain and possibly improved when performing latter repetitions. Therefore, by having minimal reductions in fatigue, cluster training can able quality maintenance and be useful for maximising power and velocity development when using countermovement and drop jumps. 2

12 CHAPTER TWO LITERATURE REVIEW 3

13 2.0 Literature Review The game of rugby union is a physical contact sport; most commonly played with 15 players, split into two groups; forwards and backs, on the field at any one time for each team with a bench of eight players maximum in the professional game. Forwards are positioned by numbers 1 to 8 (1-3 front row, 4-5 second row, 6-8 back row) and backs, who are numbered 9-15 (9-10 half backs, centres and 11, 14 and 15 outside backs). A game of rugby union lasts for 80 minutes, which is split into two 40 minute halves (IRB, 2010) with an average ball in play time of 40.5 minutes within the TOP14 (France) as found by Lacome et al (2014). The characteristic strength is widely displayed in the game of rugby union, which has evolved rapidly over the years where the physical demands have become greater on the human body and therefore athletes nowadays are physically trained in professional gym environments. The term strength can be defined as the maximal force generated by a muscle or group (Baechle and Earle, 2008), which can be seen within rugby in the form of tackling, rucking/mauling and scrummaging. In 2007, Deutsch et al found that 93 tackles would be made within a game of rugby across the team, 49 scrums and 197 incidents of rucking and/or mauling. This alone shows the physical demand put upon the body and the frequency of strength being used within a game 18 years ago, comparing that to Smart et al (2014) study results found that forwards make an average tackles and backs in 2007/08 calendar season, seven years ago. This shows the rapid increase in the physicality of the game where forwards and back are making the same, if not more, tackles in a game than the whole playing team ten years prior which is supported by Coughlan et al (2011), who also found forwards and backs making same amount of tackles while accumulating 356 impacts (which include tackling, rucking/mauling and scrummaging) for a forward and 207 for a back. The game of rugby union has the ability to allow athletes to generate force at different velocities to create an all-round performance. These aspects are maximal strength, power, speed-strength and speed. The force-velocity curve is the relationship, seen in figure 1, between velocity and force, as movement velocity decreases as force increases (Bompa and Haff, 2009). 4

14 Figure 1 Force-Velocity Relationship and Aspects Involved. From (Accessed January 12 th ) The term strength is widely used throughout strength and conditioning to describe an important ability within sport to produce maximal effort, but as stated before the maximal force generated by a muscle or group (Baechle and Earle, 2008). Strength has become a major contributor to training and sporting activities as past literature suggests that high levels of strength are present and related to sport performance and as seen in figure 1, maximal strength can be seen at the top of the force-velocity curve, where maximal force is produced at slow velocities. This can been seen in the game of rugby in the form of scrummaging where Cunniffe et al (2009) found that a forward would undertake impact at scrum time 56 times, 19 first half and 35 seconds half, within one match at elite rugby (Wales, Scotland, Ireland and England). Also forwards, on average, would be involved with 244 tackle collisions to a backs reasonable 107 tackle collisions, which demonstrates the high levels of strength needed in elite rugby. Compare this to Virr et al (2014) study, looking at the physical demands of elite women s rugby, in Canada; found scrums with a mean time of seconds. From this statistic, it is clear that high levels of strength are needed, even though there is a significant difference between the two genders, due to the number of scrums that occurred but also for the time each scrum lasted, which means that these athletes would need to be applying maximal force for quite a longer duration of time, in rugby terms which adds up almost five minutes in game play (Virr et al, 2014). 5

15 Strength-speed is an aspect of the force velocity curve that is present in rugby union, where it looks at the strength qualities more so than speed while looking at training loads of 60% 1 rep max (RM) (Baechle and Earle, 2008; Bompa and Haff, 2009). As seen on the force-velocity curve, figure 1, strength-speed is below maximal strength, and can be seen with movements such as hand off, positive tackle collision (Gain line success / tackle dominance by breaking tackle) and line breaks. Kilduff et al (2007) found that professional rugby players working at 80% of 1RM during a hang power clean produced peak values W, which shows that the ability to move a heavy resistance at speed is ideal and helpful when it is replicated in a sporting situation to a professional level. Speed-strength is found towards the bottom of the force-velocity curve, see figure 1, where minimal force is applied to gain great amounts of speed and power (Hendrick, 1993). Speed can be split into two groups, fast stretch-shortening cycle (Fast SSC) and slow stretch-shortening cycle (Slow SSC), where fast SSC would be more reactive quick energy while slow SSC would be stronger which can be seen in lineout lifting and aerial jumping, from a backs point of view. The difference between fast SSC and slow SSC movements is based on the duration of ground contact or force application, where fast SSC is ms compared to slow SSC ms. Changes in the stretch-shortening cycle can be found independently to maximal muscle strength in highly trained athletes (Plisk, 2000). As found by Virr et al (2014) that lineout lifting occurred during a match with a duration of 0:18 + 0:30 seconds, which emphasises the slow stretch-shortening cycle due to the length of time set in a semi-squat position ( ms), for a forward and jumping occurred for a back. To improve these qualities, plyometric training is suitable as rugby has some kind of pre-stretch and countermovement force and power output, increases can be made to improve performance (Cormie et al, 2011). The power output increases occur from the muscle and tendon interactions during the transition between the concentric and eccentric contractions (Gamble, 2013). 2.1 Strength Training Within traditional strength training programmes, physiological adaptations can be categorised into two groups, either neurological or morphological (Folland and Williams, 2007) where neurological adaptations include factors as motor unit recruitment, motor unit synchronization, motor unit firing rate and reflex activation. While morphological adaptations include factors as changes to muscle size, muscle hypertrophy, muscle fibre transitions and alterations to muscle architecture. Therefore, appropriate application of 6

16 strength training programmes can alter the human body in a way that can improve an athlete s capability to produce force and improve sporting performance factors such as power and speed (Bompa and Haff, 2009). This can be seen within Warman et al (2000) study using semi-professional rugby league players where they looked at the effect of a six month pre-season conditioning programme targeting muscular strength and aerobic endurance qualities. Warman et al (2000) reported an increase in 3RM squat and bench press strength between %, which can suggest that appropriate application through a pre-season block can gain improvements but one can assume that the population used with Warman et al (2000) was mixed with a high and low training age group due to the range difference of improvement. Although strength training programmes are good for muscular and sporting performance development, literature suggests that variations can be introduced, by manipulating training load, number of sets, number of reps, set configuration and the exercises selected (Haff et al, 2008). As a strength and conditioner based in team sports, such as rugby, it is important that players have a strong foundation of strength in all movements and therefore require optimal levels, if not maximal at times, of strength to successfully compete and suggested literature states that professional players are heavily dependent on their strength levels (Baker and Nance, 1999; Murray and Brown, 2006). The options available for strength and conditioners to develop strength can vary depending on training goal (Bompa and Haff, 2009). Some of the options available are the use of body weight exercises, elastic bands, weighted objects use that is chains, sandbags, kettle bells and medicine balls, and free weights (Harman, E. 1994). Although most commonly used methods are body weight and free weights, which can be prescribed in programmes as upper and lower body exercises, Push and Pull exercises, and super and compound sets which can all provide stimulus for strength adaptations (Baechle, Earle and Wathen, 2008). All methods stated can be used in a traditional structured programme where training load varies on a weekly basis to maximise adaptations and allow athletes to achieve peak performance at competition time (Loturco et al, 2013). With training load being varied week on week to maximise adaptations, Coutts et al (2004) purposed that strength and power can be maximised through direct supervision by a strength and conditioning coach in young rugby league players through a 12 week resistance programme. During the study, 42 young rugby league players ( years) took part and were split randomly into a two groups, supervised and non-supervised. All players would undergo testing measurements of 3RM bench press, 3RM squat, maximal chins, 7

17 vertical jump, 10 and 20 metre sprints and body mass at pre-test, mid-test and post-test. Results found by Coutts et al (2004) both groups had increased in their testing measurements, where the supervised group significantly increasing their scores at midtest and post-test, and completing more sessions than the non-supervised group. Therefore Coutts et al (2004) stated that supervision and appropriate application by a strength and conditioning coach with young players can produce maximal results in sessions and testing. 2.2 Cluster Training A way of introduction a stimuli into the programme is by a set configuration called the restpause set as some may know it as or the cluster set, which has been proposed in a way where an inter-repetition rest interval is used, normally between 10 and 30 seconds, between each repetition (Haff et al, 2003). Leading towards the cluster style training methods, Lawton et al (2006) found that when training with inter-repetition rest provides a different response to what has been stated prior. The purpose of Lawton et al (2006) study was to determine the change in weight training repetition power output as a consequence of inter-repetition rest intervals. Lawton et al (2006) used 26 elite junior male basketball (n = 12, age years) and soccer (n = 14, age years) and placing them into one of three groups 6 x 1 repetition with 20 seconds rest periods (singles), 3 x 2 repetitions with 50 seconds rest periods (doubles); or 2 x 3 repetitions with 100 seconds rest periods (triples). This is a strength for Lawton et al (2006), as they are using elite junior athletes that are the best at their sport, which can show a good representative for that population. Lawton et al (2006) found from the study that by having an inter-repetition rest intervals during the programme for each group, had significant increases in repetition power outputs in the later repetitions creating a greater total power output but no difference between the groups. Hardee et al (2012) also used interrepetition rest or cluster set configuration on power clean technique in ten recreational weightlifters (age = years; body mass = kilograms; height = metres; power clean 1RM/body mass = ) with four years weight training experience and one year weight lifting experience. Already, the strength of Hardee et al (2012) study is the participants, as they very similar in anthropometry, training age and weight lifted to body weight. The study would consist of participants working at 80% of a 1RM of three sets of six repetitions with zero, 20 and 40 seconds rest, in a randomised order. Results founds by Hardee et al (2012) as the rest increased between repetitions, the power clean technique was maintained and can assume that force production was 8

18 greater. Similar results were found with Girman et al (2014) where they also used cluster training within resistance trained males. The purpose of Girman et al (2014) study was to see the effects that cluster training had on hormonal, metabolic and performance measures while comparing it to traditional training. The participants were of similar age and anthropometry of Hardee et al (2012) study, using 11 resistance trained males aged years; cm height; kg body mass. Once again a strength of the study is the participants used, as they are very similar in both studies previously. Girman et al (2014) then tested these participants on 1 repetition maximums (1RM) in clean pull, back squat and bench press. Once after completion each individual was assigned a group, at random, cluster or traditional and completed two sessions prior to retesting. Results found that after re-testing levels of growth hormone, cortisol and blood lactate levels significantly increased in both groups but had no interaction, while the cluster group were significantly greater in countermovement and standing long jumps. From these results, Girman et al (2014) suggested that the cluster group were less metabolically stressed and therefore able to maintain consistency with jump performance. Within cluster training, just like any other method, variables can be manipulated and can be structured in serval different ways. These variables that can be manipulated are Intensity, Volume, Inter-Rep and Set rest period, and Cluster configuration (Bompa and Haff, 2009). Intensity can be referred to the amount of weight lifted and therefore manipulated in cluster training due to the decrease and rest in between repetitions, which can allow athletes to train at higher intensities. For example suggested literature states that strength training zones is from around 80% of the 1RM, but with the decrease in repetitions and rest periods between each repetition also, intensity can be increased and target a much higher training zone (Bompa and Haff, 2009). Volume, which can be quantified by number of sets and repetitions completed, can also be manipulated by exactly that (Bompa and Carrera, 2005). Sets and repetitions have a relationship when looking at cluster configuration, where sets stay low and repetitions can become a high figure. But cluster sets can be used in the opposite way where the number of sets are high in comparison to repetitions, which links into intensity with some literature using this type of method (Bompa and Haff, 2009; Lawton et al, 2006). Inter-rep and set rest can also be manipulated within a cluster set. As stated before they have been proposed in a way where an inter-repetition rest interval is used, normally between 10 and 30 seconds, between each repetition (Bompa and Haff, 2009). This is because within this time ATP can be restored up to 70% after 30 seconds, so working with in these time frames can be 9

19 advantageous as physiological adaptations can occur where increases to the capillary density, mitochondrial density and buffer capacity (Willardson, 2006). Although it will take two to four minutes for PCr to approximately restore to around 84 to 89% (Complete resynthesis of ATP will occur in this time) which would be more suitable for rest periods in between sets, so that force and power production is not compromised (Willardson, 2006). Cluster configuration can be split into three groups; Singles, Doubles, and Triples. This means that with cluster training rest will be taken after every repetition, every two, or every three repetitions depending of the training goal (Bompa and Haff, 2009). Dependent on rest, in theory the higher the reps performed, use that is triples, would be more fatiguing as the rest in between each configuration would be physically demanding on the athlete. There is very limited research in cluster training prescription but there is literature out there to show effectiveness in a strength and conditioning environment. Leading on from the Singles, Doubles and Triples Hansen et al (2011) worked with 20 professional and semiprofessional rugby plyers during a jump squat, using this method. Hansen et al (2011) used four different set configurations, one traditional configuration of 4 x 6 repetitions with three minutes rest between sets, the second (Cluster 1) 4 x 6 x singles with 12 seconds of rest between repetitions, the third (Cluster 2) 4 x 3 x doubles with 30 seconds rest between each double (every two reps), and the fourth (Cluster 3) 4 x 2 x triples with 60 seconds rest between each triple (every three reps). Results found that the cluster groups tend to maintain peak power output and velocity on the jump squat compared to traditional training, with cluster group 3 (Triples) having the greater maintenance of all. Compare this to Arazi et al (2013) study who looked at inter-rep rest till failure in bench press and leg press with three different cluster groups; zero, two and four second rests after each repetition. 20 college age men would work at 75% of their 1RM on bench and leg press over four sets with three minutes rest period between sets. Results from Arazi et al (2013) found that there was a massive decrement from set one to set four across each inter-rep rest group to the point of repetitions almost being halved. 2.3 Testing Approaches Methods for testing approaches can differ depending on the quality that is looking to be tested with many methods to choose from. Testing for strength requires maximal force and slow velocity, even though the intention is to move the bar fast, and there are numerous methods in doing so. One method for testing maximal strength is the 1RM bilateral back squat (Todd, 2012). The 1RM bilateral back squat is widely used when looking to test 10

20 lower limb maximal strength with athletes and has been successfully been used with the protocol suggested by Earle and Baechle (2008), testing protocol used in this study (Moir et al, 2005; 2007). Reliability and validity of the 1RM bilateral back squat have shown to be moderate to very high correlations between 1RM squat and athletic performance such as sprinting and over time have been able to differentiate between playing positions and playing level within sport (Carbuhn et al, 2008; Fry and Kraemer 1991). Testing maximal strength can also be done via machined weights such as a leg press machine. When using a leg press machine, it requires the subject to sit in the leg press chair with both feet on the plate and look to have a 90 degree angle at the knee joint (Phillips et al, 2004). Although may it be used as a method for maximal strength of the lower limb, it is only used within the older population due to safety reasons of using free weights as suggested by Hoffman (2006), Foldvari et al (2000) and Marsh et al (2009). A weakness in the machined leg press is the ability to be established as a assessment method within general population due to the functional status it holds with the older population and shows no relevance to a sporting environment where mobility through range is advantageous (Foldavri et al, 2000). An argument can be made for the use of a 1RM unilateral back squat due to many sporting activities require unilateral force production such as running and kicking (Moir, 2012). Although there is no current published data to validate this test, therefore the use of this test can show no significance in this study. Testing for power requires high levels of force with high levels of velocity. Movements such as this can be seen with Olympic lifting, using clean and snatch protocols (Kilduff et al, 2007). More so the power clean is used as a method of testing power within gym based environments and has shown to be have positive relationships with other factors on the force velocity curve (Owen et al, 2014; Bevan et al, 2010). Although it should be noted that the power clean is a technique intensive and therefore, athletes of the same characteristics can produce different results. Other tests used for power is the Margaria- Kalamen test which is a devised stair sprinting test to predict power output (Fox, Bowers and Foss, 1993). This test can allow power output to be calculated based on vertical distance covered, time to complete and body mass where the test has been used with numerous populations that has provided valid measures of peak power (Peterson, 2012). 11

21 Implications of this test is the ability to find an environment with a staircase that has a flat lead-up of around six plus metres with equipment to calculate power output. When testing speed-strength qualities, it can be separated into two categories; fast stretch-shortening cycle (Fast SSC) and slow stretch-shortening cycle (Slow SSC). One test used for slow SSC is the countermovement jump (CMJ). The countermovement jump is commonly used test worldwide for testing fast speed-strength qualities (Slinde et al, 2008) and uses a combined eccentric / concentric muscle contraction. The test can be modified by using an arm swing or the removal of it by hands being fixed on hips. Slinde et al (2008) found that measuring a countermovement jump with arm swing was significantly greater compared to a countermovement jump without arm swing, although it has been noted that a countermovement jump without arm swing is shown to be more reliable to represent lower limb strength. The other test for slow SSC is a modified countermovement jump which is the squat jump, where the difference is the participant squats to parallel (knees at 90 degree angle) and hold for a two seconds isometric contraction (Peterson, 2012). The squat jump is an effective test for assessing concentriconly movement which can be used alongside a countermovement jump. Moving towards the fast SSC assessment, the drop jump can be used, where the participant drops from a box to the ground and look to jump as high as possible with minimal ground contact time (Earp et al, 2010). Both fast and slow SSC can be linked with the reactive strength index (RSI) as reactive strength occurs during explosive movement, ones that involve high force and high speed. This is more so for fast SSC such as the drop jump, where the aim of the test is to produce maximal force in a short space of time, therefore it can be suggested that the higher the jump, with low ground contact time, the higher the reactive strength index will be (Poussen, Van Hoeke and Goubel, 1990; Flanagan, Ebben and Jensen, 2008). 12

22 CHAPTER THREE METHODS 13

23 3.0 Methods 3.1 Participants There were 22 male college academy group players that agreed to take part in the study, (age = years old). Participants had at least one year of weight training, and one year experience of Olympic weightlifting. 3.2 Ethical Approval Prior to the start of the study, it went through the process of ethical approval at Cardiff School of Sport ethics committee. Once ethical approval was granted, assent and consent forms were sent out and signed by the participants parents to allow their child to participate in the study prior to their participation. 3.3 Protocol Firstly the participants had weight and height measurements taken prior to testing, with shoes off and in shirt and shorts, which were conducted using a stadiometer (Holtain Fixed Stadiometer, Crymych, Pembs) for height and digital scales (SCEA-Model 770, Hamburg, Germany) for weight. Due to the training block taking place in-season; Participants would have been undertaking other training sessions such as skill and position specific training sessions with possible game play with the academy. Therefore a register was used for the participants throughout, where duration of the session was recorded and then the participants would give a RPE score (Rate of Perceived Exertion) out of 10 (McArdle et al., 2014) upon completion of each session. This is to ensure all sessions within and outside of the study, are all rated similarly across the board of the two groups. Therefore, for the period of the training block the participants were requested not to do any strenuous or extra exercise outside of the academy sessions and to maintain normal dietary habits. 3.4 Testing Procedures The 1 RM Back Squat test will follow the protocols as outlined by Baechle and Earle (2008, p. 254) using a 20kg barbell (Eleiko, Olympic WL Training Bar, Eleiko Sport, Halmstad, Sweden), weight plates (Eleiko, Olympic WL Training discs, Eleiko Sport, Halmstad, Sweden) and power racks (Power Rack, Performance Power Rack, Perform Better Limited, Southam, Warwickshire). Participants undertook a standardised RAMP warm up (See table 1.) upon arrival at the gym. They were familiar with the testing protocol as they have been deemed technically competent by a Strength and Conditioning 14

24 coach. Participants went through a progressive series of loaded warm ups before they were allowed a maximum of five attempts at a 1RM load. Spotters were in place throughout and only attempts where the femur is parallel to the floor were counted. 1 RM Power Clean test will follow the protocols as outlined by Baechle and Earle (2008, p. 255) using a 20kg barbell (Eleiko, Olympic WL Training Bar, Eleiko Sport, Halmstad, Sweden), weight plates (Eleiko, Olympic WL Training discs, Eleiko Sport, Halmstad, Sweden). Participants would have undertook a standardised RAMP warm up (see table 1.) upon arrival to the gym. They were familiar with the testing protocol as they have been deemed technically competent by a Strength and Conditioning coach. Participants went through a progressive series of loaded warm ups before they were allowed a maximum of five attempts at a 1RM load.. Counter Movement Jump (CMJ) and Drop Jump tests will follow the protocols similar to Earp et al (2010) using a contact mat (Smartjump, Fusion Sport, Brisbane, Australia). Participants would have undertook a standardised RAMP warm up (see table 1.) upon arrival to the gym. They were familiar with the testing protocol as they have been deemed technically competent by a Strength and Conditioning coach. Participants would have been provided with a progressive series of jumps before being allowed two practice jumps. Participants would have then undergone three tested jumps, taking the best score out of the three, with the emphasis on jumping as high as possible and as fast as possible. Participants would have fixed their hands on their hips throughout the jumps at all times to isolate lower limb speed strength qualities. 15

25 Table 1. Standardised RAMP warm up protocol RAMP Warm up Protocol Exercise Sets Reps Sumo Squat 2 Length Over Head Lunge 2 Length Mountain Climbers 2 Length Inch Worms 2 Length Calf Pistons 1 10 each leg Hamstring Kicks 1 10 each leg Long Lying Gluteus Stretch 1 5 each leg / 2 second hold Air Squat 1 3 Squat to Toes 1 3 Jump Squat Data Analysis The data collected can be analysed by using a 2 way mixed ANOVA to show any significance between height, weight, squat, CMJ, drop jump, contact time and RSI scores between each group and interaction. During post-hoc analysis a Bonferroni correction was used in all tests run. Once collected the participants results were entered into a Microsoft Excel spread sheet in a table format of each individual, training group, pre-test scores and post test scores (see appendix 1.). After the data was presented into a table in Microsoft Excel, it was then transferred over to SPSS (IBM SPSS Statistics 20, IBM United Kingdom Limited, North Harbour, Portsmouth, Hampshire, United Kingdom). 16

26 CHAPTER FOUR RESULTS 17

27 1RM Squat (Kg) 4.0 Results 4.1 Anthropometrics Table 2. General Characteristics of the participants (n = 22) Training Group Pre Post Height Cluster cm cm Height Traditional cm cm Weight Cluster kg kg* Weight Traditional kg kg* *Represents significant difference in weight P < Table 2 shows the general characteristics of the participants were similar in height between the groups but there was no significant height difference ( = 0.952, F 1,200 = 1.0, P = 0.329) with a significant weight difference from pre testing to post testing ( = 0.424, F 1,200 = 27.2, P =0.000) but no interaction with weight between the groups ( =1.000, F 1,200 = 0.1, P = 0.942). 4.2 Strength 1RM Squat Cluster Pre Cluster Post Traditional Pre Traditional Post Figure 2. Mean 1RM squat scores from pre and post testing for both groups. *Represents a significant difference to 1RM squat performance P < Values are reported Mean + SD. 18

28 CMJ Jump Height (cm) Figure 2 shows that the scores for the 1RM squat improved significantly from pre to post testing for both training groups ( = 0.536, F 1,200 = 17.9, P = 0.000) but there was no significant difference between both groups squat scores at pre or at post testing ( = 0.962, F 1,200 = 0.8, P = 0.382). Note that the cluster group had a lower baseline score compared to the traditional training group. 4.3 Slow Speed Strength CMJ Cluster Pre Cluster Post Traditional Pre Traditional Post Figure 3. Mean CMJ score from pre and post testing for both groups. *Represents a significant difference to CMJ performance P < Values are reported Mean + SD. Figure 3 shows that the scores for CMJ jump height improved significantly for both groups ( = 0.067, F 1,200 = 279.2, P = 0.000), with a significant difference between group CMJ scores ( = 0.301, F 1,200 = 46.4, P = 0.000). Note that the cluster training group had a lower baseline score compared to the traditional training group. 19

29 4.4 Fast Speed Strength Drop Jump, Ground Contact Time and RSI Table 3. Drop Jump Height, Ground Contact Time and RSI scores (n = 22) Group Pre Post Drop Jump Height Cluster cm cm* Drop Jump Height Traditional cm cm* Contact Time Cluster ms ms Contact Time Traditional ms ms RSI Cluster RSI Traditional *Represents a significant difference to Drop jump performance post-test P <0.01. Table 3 shows that there was a significant change in drop jump height scores from pre to post testing in both groups ( = 0.330, F 1,200 = 40.5, P = 0.000) but no significance between the groups at pre or post testing ( = 0.940, F 1,200 = 1.3, P = 0.274), no significance in contact time at pre or post testing between the groups ( = 0.947, F 1,200 = 1.1, P = 0.305) or its interaction at pre or post testing ( = 0.998, F 1,200 = 0.1, P = 0.831) and no significance in RSI at pre or post testing( = 0.937, F 1,200 = 1.4, P = 0.258) or its interaction at pre or post testing between the groups ( = 0.998, F 1,200 = 0.1, P = 0.832). 20

30 CHAPTER FIVE DISCUSSION 21

31 5.0 Discussion The purpose of the study was to examine the difference between traditional strength programmes and cluster strength training with reference to their effects on the forcevelocity curve characteristics within collegiate academy rugby union players. Although there is an abundance of literature published in the field of strength training, there is a shortage of research in cluster training within collegiate academy rugby union players and comparing both, strength and cluster, to see which has had the most positive effect on the force velocity curve. Results indicated that both traditional strength programmes and cluster training are both adequate tools for developing strength qualities but cluster training seeming to have a greater effect but not significantly greater on the lower end of the force velocity spectrum targeting more speed-strength qualities. 5.1 Anthropometrics From an anthropometric characteristic side of the study, both groups saw significant morphological adaptations where an average increase mass of 1 ± 1.1 kg was observed. This supports Folland and Williams (2007) where potential muscle hypertrophy occurred, either in the upper or lower body as of a result in resistance training. Although it can be said that a morphological adaptation has occurred, it would be deemed insignificant as an average change of 1kg in body mass is not a huge difference in sporting context. Compared to recent studies Gabbett (2005) where he looked into physiological and anthropometric characteristics over a competitive season in junior rugby league players aged 13 to 16. Gabbett (2005) results found that over a competitive season, no changes in anthropometric characteristics were obtained. This can because the training loads and match intensities were not physically demanding enough for morphological adaptations to occur. Note that no resistance training took place during the season long study. On the other hand Baker and Newton (2006) looked into adaptations from resistance training in experienced elite and sub-elite rugby league players. Over a four year period, Baker and Newton (2006) found that there was a significant increase in body mass of up to 5% for the first two years, 1998 to 2000, and then remained unaltered from 2000 to 2002 in both groups. This change in body mass lead to an increase in strength scores and power output on a 1RM bench press and bench press throw within both groups and overall. So from Baker and Newton (2006) study, it can be suggested that anthropometric adaptations can occur even within elite athletes, therefore players who are exposed to resistance training with lower training ages can experience greater changes in body mass as observed by Folland and Williams (2007). 22

32 5.2 Strength At the top end of the force velocity curve, a significant increase in 1RM squat scores were achieved which can be linked back to Folland and Williams (2007) where if strength levels increase then it is a good sign that neurological and morphological adaptations have occurred due to the changes in muscle architecture and size, motor unit recruitment, synchronization and firing rate. It can be said that both traditional and cluster training can be very useful in the development of strength where the cluster group increased their 1RM squat by around 10% and the traditional group by around 6%. It is important to note that the cluster group had a lower baseline score compared to the traditional group which can be seen clearly in figure 2, therefore one can assume that during pre-testing the traditional group were the stronger of the two groups but to have the squat score difference decrease after post-testing. Factors causing this affect can be due to a younger training age within the cluster group compared to the traditional group, therefore having a greater strength adaptation because of the exposure to a strength stimulus as well as cluster configuration. This has been seen by Folland and Williams (2007) where individuals who have low training ages or untrained have a greater hypertrophic response to resistance training. According to Coutts et al (2004), strength and power within young rugby league players can be maximised through the application of a resistance programme with direct supervision from strength and conditioning coaches. Coutts et al (2004) found that throughout a 12 week programme, players can have significant increases in 3RM bench press and squat, vertical jumps and speed scores which can support the results presented previously that resistance training can have an effect on the force velocity curve within collegiate academy players. This can support Haff et al (2001) study as the use of explosive exercises, use that is clean, squat, deadlift and jerk, can result in improvements in power and strength production, although training age is young and adaptations in strength and power would have rapid increases, it shows correct application of a strength programme can see improvements in explosive qualities and changes on the force velocity curve. 5.3 Slow Speed-Strength When looking to increase countermovement force and power output the use of plyometric training has be suggested a viable option more so for an intermediate to advanced level athlete as changes in the stretch-shortening cycle can become limited through strength 23

33 training (Cornie et al, 2011; Plisk, 2000). Therefore it can be argued that strength training within young, low training aged athletes can improve countermovement force. This study found that strength training had an positive effect on countermovement force in both, cluster and traditional, training groups and saw a significant increase in countermovement jumps with the cluster group to around 70% and the traditional group to around 20% on average. It should also be noted again that the cluster group had a low baseline score compared to the traditional group, which can be assumed once again, with the same reason as strength, that the cluster group had a lower training age compared to the traditional group and therefore came out stronger at pre-testing where results at posttesting had no difference between groups. It can be suggested that cluster training can be used as a suitable method for developing speed-strength qualities as seen in figure 3, which can and be supported by Hansen et al (2011) where results found that cluster groups tend to maintain their peak power output and velocity on jump squat compared to traditional training groups. Compare this to Ronnestad et al (2008), where they found that during a seven week training block, there were no significant improvements in countermovement jumps but more so in jump squats. Therefore during the study of Ronnestad et al (2008), it can be made clear that strength training had no effect on the speed-strength qualities of the force velocity curve. Although Ronnestad et al (2008) found no results of strength training effecting speed-strength qualities, Girman et al (2014) did. Girman et al (2014) found that cluster training compared to traditional training had greater effects for countermovement and standing long jumps, which shows that the cluster training is less metabolically taxing therefore resulted in consistent jump measures. 5.4 Fast Speed-Strength Regarding the slower speed-strength qualities it can be seen that throughout both groups drop jump height increased, along with ground contact time and relative strength index (RSI). It is important to note that there was a significant increase made in drop jump scores in both groups, where the cluster group increasing their score by 10cm and the traditional group by 6cm on average. Unlike squat and CMJ scores at baseline testing, there was no difference between the groups therefore results at post-testing can allow for interpretation to which training programme provided the better adaptation. In this case, as seen in table 3, both groups saw significant increases in drop jump height scores but the cluster training group made more of a difference comparing to baseline testing on average. Although drop jump height scores increased, so did ground contact time on average for both groups. As a result of this the athletes are spending longer on the floor to generate 24