Appraisal of the Physiological Underpinnings and Testing Requirement for a Semi-Professional Football Player
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Appraisal of the Physiological Underpinnings and Testing Requirement for a Semi-Professional Football Player
Word Count: 2372
Candidate Number: Z0 948612
Degree: Sport, Exercise and Physical Activity BA (hons)
The following report undertakes an individual assessment on a 21-year old, male, defensive footballer, who currently plays in the second division of the Wearside football league. In undertaking this assessment, it aims to establish both inter-personal and sport specific needs, which can then be used for the design and implementation of a testing programme. Once the needs of the subject and the sport have been sufficiently explored, relevant methods of testing are selected, then implemented, using evidence-based testing protocols. The overarching aim of this report, is to establish performance indicators which could then be used to aid the development of an individualised training programme.
Football is a team sport which is most commonly played with 11 players on each team; the overarching purpose of the game, is to use a variety of kicking techniques to stop the ball entering one goal and get it into the opposing teams (FA, 2016). Elite football, demands a unique blend of athletic capabilities ranging from aerobic endurance to explosive power and repeated sprint speed (Hoff, 2005). When combined with technical proficiency and tactical awareness, high levels of performance can be achieved (Bloomfield, Polman, and O’Donoghue, 2007). At the elite level, players have been shown to cover distances between 10-13 Km and undertake between 150-250 more demanding, explosive style movements (Mascio and Bradley, 2013; Osgnatch et al., 2010). More specifically, elite players distribute their efforts as shown; standing 19.5%, walking 41.8%, jogging 16.7%, running 16.8%, sprinting 1.4%, and other 3.7% (Mohr et al., 2003). Due to extended periods of moderate activity, metabolic analysis suggests football is predominantly dependent on the aerobic energy system; however, crucial moments during a game are more commonly defined by short, high intensity bouts of activity, which are typically funded by the anaerobic energy system (Sporis et al., 2009). The following paragraphs further explore, the nature of the defensive position and specific attributes, considered crucial to performance within it.
It should be noted, that there are considerable differences in the nature of the activities which are performed across the different positions on the pitch (Bloomfield et al., 2005). When looking at defenders, it has been shown that they perform the highest amount of jogging, skipping and shuffling movements, as well as undertaking a considerable amount of physical duels (Bloomfield, Polman, and O’Donoghue, 2007; Dellal et al., 2011).
Due to the unpredictable nature of football and more specifically, the frequent direction changes associated with defensive positions, agility was identified as an important attribute in football fitness (Bloomfield, Polman, and O’Donoghue, 2007). Agility, can be further understood as the ability to maintain optimal body positioning whilst quickly changing direction (Twist and Benicky, 1996). Agility, is said to be dependent on efficient motor programming, which can be achieved through neuromuscular conditioning and the neural adaptation of muscle spindles (Barnes and Attaway, 1996). When tested, elite level players demonstrated superior levels of agility over sub-elite players, supporting the notion that it’s an important factor within football fitness (Kaplan, Erkmen, and Taskin, 2009).
Due to the varied nature of football and more specifically, the physical duels associated with defensive positions, power was identified a crucial component of an elite defender (Hoff, 2005). Power, can be further understood as the ability to reach maximal velocity in the shortest amount of time (Cormie, McGuigan, and Newton, 2011). Physiologically, power is highly dependent on sarcomere position, the largest amount of potential is available when optimal overlap between actin and myosin filaments is achieved; this is because at this point active tension is at its greatest, enabling muscles to contract with peak velocity (Gordon, Huxley, and Julian, 1966). When tested, elite level players demonstrated superior levels of power when compared with sub-elite, supporting the notion that it’s an important factor in football fitness (Le Gall et al., 2010).
Although the majority of a football match is spent working at low speeds, crucial moments in the game are more commonly defined by short, high speed intervals (Sporis et al., 2009; Reilly, Bangsbo, and Franks, 2000). Thus, sprint speed was deemed an import attribute for an established performer to possess. Physiologically, speed is commonly associated with power and also depends on optimal contractions between actin and myosin filaments; however, research instils that the relationship is not completely linear and suggests sprint speed is also largely dependent bio-mechanics and motor unit efficiency (Gordon, Huxley, and Julian, 1966; Tønnessen et al., 2011). Whilst sprint speed can be associated with power to some extent, due to some variability, it is apparent that both power and sprint speed need to be considered individually. When tested, elite players demonstrated superior levels of acceleration and prolonged sprint speed, when compared with sub-elite players, supporting the notion that it’s an important attribute to possess (Little and Williams, 2005).
As extended periods of a football match are spent working at relatively intensities, cardiovascular fitness can be considered an important component in football fitness (Bennike, Wikman, and Ottesen, 2014; Stolen et al., 2005). Furthermore, Russell and Kingsley (2011) explain, fatigue is highly debilitating to football performance, primarily because of the effect it has on skill acquisition. Thus, cardiovascular fitness can be considered highly important when aiming to maintain good performance. The onset of fatigue is said to negatively affect the body in two ways, one of which is lactate accumulation, which occurs when the body can no longer ...
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As extended periods of a football match are spent working at relatively intensities, cardiovascular fitness can be considered an important component in football fitness (Bennike, Wikman, and Ottesen, 2014; Stolen et al., 2005). Furthermore, Russell and Kingsley (2011) explain, fatigue is highly debilitating to football performance, primarily because of the effect it has on skill acquisition. Thus, cardiovascular fitness can be considered highly important when aiming to maintain good performance. The onset of fatigue is said to negatively affect the body in two ways, one of which is lactate accumulation, which occurs when the body can no longer utilise oxygen to process pyruvate and results in the production of excess lactate; the second is heat accumulation (i.e. hypeI~hermia), which can reduce enzyme activity (Berg, Tymoczko, and Stryer, 2002). Both lactate accumulation and excessive levels of heat have been shown to negatively impact the mechanical efficiency of cellular respiration, which limits the body’s available energy, thus, negatively impacting performance (Shephard and Astrand, 1993). Elite athletes have been shown to facilitate superior levels of cardiovascular fitness when compared with sub-elite performers, supporting the notion that it is an important component in football fitness (Ingebrigtsen et al., 2012).
The relevance of body composition in sports performance is widely appreciated, specifically, for its capacity to illuminate a player’s physical status and provide a relevant indicator of their performance potential (Leedy, Ismail, Kessler, & Christian, 1965). Body composition has shown a considerable association with aerobic capacity and energy expenditure; when excessive, body fat can be considered a dead weight and ultimately negatively impacts a player’s capacity to perform (Reilly, 1996). In addition, lean muscle mass and a good strength-to-weight ratio has been associated with superior sports performance (Gabbett, 2005). Miller et al. (2011) found, elite players would generally maintain lower levels of body fat throughout the season, supporting the notion that low body fat levels are associated with superior performance.
Needs Analysis
In the context of sport, the SWOT analysis is a tool which is typically used to evaluate the internal and external factors which can impact sports performance (Johnson and Scholes, 1999, cited Dyson, 2004). More specifically, the SWOT identifies potential strengths, weaknesses, opportunities and threats, which are relevant to athletes when they perform (Dyson, 2004). Having identified these factors, strategies can be developed which can help build on an athletes strengths, abolish their weaknesses and enable them to exploit potential opportunities (Dyson, 2004). Rego and Nunes (2010) propose, the SWOT analysis provides an effective method of establishing attainable aims and objectives, which can then be used to aid development.
The subject identified that they have a base knowledge in sport, fitness and training, which could aid the development of a testing/ training programme, as they can offer some understanding into why certain methods are put in place (Desharnais, Boullion, and Godin, 1986). Furthermore, the subject identified that they have a range of opportunities to use sporting facilitates, which has also been shown to aid athletic development (Cadrant and Lent, 1987). Overall, the subject appears to be in a good position to facilitate progression. Physiologically, the subject identified strength/ power and composition as their strengths.
The subjects schedule however, was identified as a potentially limiting factor; as a full time student and individual with various sporting commitments, adding further training could prove difficult (Carodine, Almond, and Gratto, 2001). In terms of current physiological determinants, the subject acknowledges that they are currently not agile enough to play in their current position; they also recognise they are shorter than the average elite level defender, although accepted that this is not something that they could develop.
Overall, the SWOT analysis helped establish more individualistic physiological determinants, which could prove more relevant to test and develop (Vallet et al., 1997).
As part of the needs analysis the subject was also asked about their sporting ambitions and physical status. The subject identified themselves as injury free and stated, it was a goal of theirs to progress from Wearside Division 2, into Wearside Division 1, although acknowledged that they would need to improve significantly.
Methodology
The subject was a 21-year-old male with a mass of 76.2kg and height of 172.6cm. The participant completed a medical history questionnaire and gave informed consent prior to data collection. All lab and field based experimental procedures were approved by Durham University.
This report opted to use a combination of field based and lab based testing methods. Field based testing holds many advantages when used within the context of sport, they typically provides a less intrusive, more efficient means of testing (Winter et al., 2006). Coaches commonly use field based methods during talent identification, in order to reduce any time/ expenditure associated with testing unwanted personnel (Castro-Pinero et al., 2009). However, whilst convenient and efficient, field based methods lack the precision and detail associated with lab based methods (Winter et al., 2006). Coaches would more commonly use lab based methods when working with elite personnel (Svensson and Drust, 2005).
V0₂max (relative)
The V0₂ max, can be defined as a test which aims to identify the “maximum rate at which an individual can take up and utilise oxygen while breathing air at sea level” (Astrand and Rodahl, 1986, P.17). This research opted for the relative V0₂ max test, as this test is capable of collecting data with greater specificity (Dlugosz et al., 2013). Specifically, this test was selected for its ability to provide a direct measurement of aerobic endurance (Powers and Howley, 2008). Furthermore, the relative V0₂ max test has been shown to operate with greater levels of accuracy than other common methods such as the multi-stage fitness test (cooper et al., 2005).
Protocols
VO2 workload began at 8kmph, increasing by 2kmph every three minutes until volitional exhaustion occurred. HR and RPE were measured at the end of every three-minute interval.
Equipment
Unknown
Vertical jump
Jump height is being measured as Gee et al. (2011) identified a relationship between vertical jump results and power output. In eliminating arm swing, Young (1994) suggests that the test provided a greater evaluation of the leg extensor muscles. The force plate data methods have been selected specifically as Aragón (2000) found, when compared with the other vertical jump protocols, force plate data was the most accurate. However, using protocols which facilitate arm motion, could have created results more relatable to actual performance, as players are unlikely to jump with self-restricted arm movement. Furthermore, the
Protocols
The subject was required to stand in an erect position, placing their hands on their iliac crest, then squat to their perceived optimal depth and then jump vertically. The subject was required to jump 3 times and take 2 minute breaks between each jump, following protocols develop by Ostojic (2006).
Equipment
Probiotics, Just Jump, Huntsville AL.
T-test
The T-test has been selected as Semenick (1990) states it is a valid test for evaluating agility. More specifically, LeonCarlyle (2008) suggests the t-test evaluates a range of specific traits which are required on a football pitch, for example, foot speed, power and direction change (Sheppard and Young, 2006). LeonCarlyle (2008) suggests that coaches and trainers found, t-test results matched which the players they deemed to be the most agile further supporting the tests validity and reliability.
Protocol
Set out four cones in the shape of a T placed 5 yards apart. The subject starts at cone A, then on the command of the timer, sprints to the far left cone remaining in line with the T; once the subject touches the cone on the far left with their right hand they then shuffle laterally to the cone on the far right. Upon reaching the cone on the far right, the subject then shuffles laterally back to the central cone; finally the subject sprints remaining in a back-to-front position to the staring cone, upon reaching the starting cone the stopwatch is pressed. This test followed protocols established by Semenick (1990).
Equipment
Cones, stopwatch
Stationary start 30-meter sprint (Wingate test)
The 30m sprint has been selected as Young, McDowell and Scarlet (2001) describe the test as a raw measurement of speed. Furthermore, Zagatto, Beck, and Gobatto (2009) describe the validity of this test as exceptional, as replicates almost exactly what a performer would do during performance. The use of speed gates, improves the accuracy of the test by removing aspects of human error, which is why they have been selected for this report (Zagatto, Beck, and Gobatto). However, as a sprint during a football game is rarely from a stationary start, undertaking a moving start could make the test more valid (Cronin et al., 2007).
Procedure
Three runs were completed with two-minute rest in-between each interval to ensure maximal effort, the subject followed the guidelines presented by Ostojic (2006).
Equipment
Unknown
Bio-electrical impedance
This method provides a reliable and valid approach, for the estimation of human body composition (Lukaski et al., 1985). This method has been selected primarily because it provides a non-invasive method, capable of rapid measurements and furthermore it requires minimal operator skill, which was deemed particularly important as none of the researchers were ISAC trained (Lukaski et al., 1985; Mei et al., 2007).
Procedure
The subject followed the protocols used by Lukaski et al. (1985), no eating or drinking for 4 hours before, no exercise for 12 hours prior to testing, no alcohol in the last 48-hours, no diuretics within 7 days and urination 30 minutes prior to testing. Subjects were tested whilst in a supine, horizontal position whilst fully clothed (Lukaski, et.al. (1986).
Equipment
Unknown
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wilsonjosh94hotmailcouk (student)
