The Influence of Relative

A Sporting Chance

Enhancing opportunities for high-level sporting performance: influence of 'Relative Age' Page i Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Table of Contents

Executive Summary: page 1 Appendix 1: Summary of the research which has investigated the “Relative The Context: page 3 Age Effect” in Sport: page 26

Relative Age - Introduction: page 3 Appendix 2: Hypothetical impact of the relative age effect in sport page 30 Relative Age - The educational evidence: page 3

Relative Age - What is the evidence to suggest it exists in sport? page 4 & 21

What is the cause of the relative age effect in sport? page 21

Relative Age - A hypothetical example of the possible effect of relative age: page 22

What to do about the ‘Relative Age Effect’ - Possible Solutions: page 23

The influence of other factors on sporting opportunity: page 24 This report was written by Dr. John G. Morris and Dr. Mary E. Acknowledgements: page 24 Nevill of the Institute of Youth Sport (IYS), School of Sport and Exercise Sciences, Loughborough University, Leicestershire, References: page 24 LE11 3TU. Page ii Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

List of Figures

Major League Baseballers (male) 1985: page 5 First Class County Cricketers (male) 2006: page 10

Major League Baseballers (male) 1990: page 5 Premiership Rugby Union Players (male) 2006/07: page 10

Junior Ice Hockey Players (male) 1988/89: page 6 Elite Judo Players (Cadet) 12-16 yrs (male) 2003-2006: page 11 NHL Ice Hockey Players (male) 1988/89: page 6

U15 Finalists English Schools Athletics (male) Elite Judo Players (Juniors)16-20 yrs (male) 2002: page 7 2003-2006: page 11

U17 Finalists English Schools Athletics (male) Elite Judo Players (Seniors) (male) 2003-2006: page 11 2002: page 7 ASA Age Championship Swimmers (11-14 yrs) U20 Finalists English Schools Athletics (male) (male) 2004: page 12 2002: page 7 ASA Youth Championship Swimmers (15-18 yrs) Senior Athletes Ranked in Top 20 in their (ESAA) Event (male) 2002: page 8 (male) 2004: page 12

Senior Athletes Ranked in Top 20 in their Event Senior International Swimmers (male) 1986-2004: page 12 (male) 2002: page 8 Elite Junior Tennis Players (male) 2003: page 13 FA School Footballers (male) 6 year period: page 9 Elite Senior Tennis Players (male) 2002 / 2003: page 13 English Academy Footballers (male) 2002/04: page 9

English Professional Footballers (male) 1991/92: page 9

Premiership Footballers (male) 2006/07: page 9 Page iii Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

List of Figures (continued)

U15 Finalists English Schools Athletics (female) ASA Age Championship Swimmers (11-13 yrs) 2002: page 14 (female) 2004: page 18

U17 Finalists English Schools Athletics (female) ASA Youth Championship Swimmers (14-17 yrs) 2002: page 14 (female) 2004: page 18

U20 Finalists English Schools Athletics (female) Senior International Swimmers (female) 2002: page 14 1986-2004: page 18 Senior Athletes Ranked in Top 20 in their (ESAA) Event (female) 2002: page 15 Elite Junior Tennis Players (female) 2003: page 19

Senior Athletes Ranked in Top 20 in their Event Elite Senior Tennis Players (female) 2002 / 2003: page 19 (female) 2002: page 15

English Premiership Footballers (female) 2004/05: page 16

English International Footballers (U15-U21) (female) 2002/04: page 16

Elite Gymnasts (Female) 2004: page 16

Elite Judo Players (Cadet) 12-16 yrs (female) 2003-2006: page 17

Elite Judo Players (Juniors) 16-20 yrs (female) 2003-2006: page 17

Elite Judo Players (Seniors) (female) 2003-2006: page 17 Page 1 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

research clearly demonstrated a skewed distribution “Are the Executive Summary (and hence a relative age effect) among elite young opportunities and adult players, such that a greater proportion of to develop players were born in the first quarter of a selection into a champion The Context: sportsperson year with decreasing numbers thereafter. Based on a number of studies conducted in the early-to-mid the same for There are a wide variety of factors, such as socio- “Surely 1990s, the relative age effect was strongly evident everyone?” economic status, sex and family background, that someone’s month among junior and senior football (soccer) players. can and do influence selection and progression in of birth cannot influence Published research has also demonstrated a relative elite sport. One factor that does seem to influence their opportunities to age effect among elite junior and senior tennis high-level performance is termed the ‘relative age’ play sport. That’s a players. Further research presented in this document effect. ridiculous idea!” will show that the relative age effect is as strong as ever in football, and can also be seen in senior cricket and rugby union players. It is also evident The Relative Age Effect: in junior and senior track and field athletes (see “Is there any evidence figure below) and in young (11-14 years) and senior The relative age effect describes the observation that a relative age swimmers. effect exists in sport?” that greater numbers of performers born early in a selection year are over-represented in junior and U15 Finalists English Schools Athletics (male) senior elite squads compared with what might be 2002 expected based on national birth rates. It would 55% n=133 appear that the relative age effect, certainly in some Evidence of a RELATIVE sports, crucially influences the opportunities to AGE EFFECT? Yes “Can anything be achieve high-level sporting performance. 23% done to minimise the 14% 8% impact of the relative Relative Age In Sport - The Evidence: age effect?” Q1 Q2 Q3 Q4 Sep-Nov Dec-Feb Mar-May Jun-Aug The first studies to investigate the relative age effect Sources: http:www.esaa.net; Whittingham & Matthews were carried out in Baseball and Ice Hockey. This (Eds.) British Athletics Statistical Review 1999-2005 Page 2 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

However, recent rule changes in swimming (such that • Rotating Cut-Off Dates different performers will be age-advantaged the eligibility of swimmers to take part in events is It has been suggested that selection at different periods during a year. based on their ‘age on date’ of the competition) may years should be based on a period such explain why the effect was not seen in youth (14-18 as 9 months such that each year different • Altered Competition Structures years) swimmers. Interestingly, the relative age effect individuals in a particular group will be age- A move away from a single national does not appear to be as evident among female advantaged. competition at one time of year to a series sports performers, except in track and field athletics of important competitions spread throughout and tennis, or in a weight-classified sport such as • Reduced Age Ranges a year, where eligibility for participation is judo. Age group squads based on smaller age dependent on age on date of competition. bands (6 months rather than 12 or 24) might alleviate some of the effects of relative age. Possible Causes of the ‘Relative Age Key Question: Effect’: • Establish ‘Current’ and ‘Potential’ Squads The creation of 2 squads in a selection Can anything be done to minimise the relative age Despite the belief that differences in physical maturity group rather than just one is a another effect and so enhance the opportunities for ALL explain the relative age effect very little evidence suggested means of reducing the impact of talented young performers to progress to be high exists to support such an assertion. It has been argued relative age level sporting performers as adults? that the underlying cause of the relative age effect is actually an amalgamation of physical, cognitive, • Winning is not Everything! emotional, biological and sociological factors. An adjustment of the “winning is everything focus” often evident in junior sport among performers, coaches, parents and others is What to do about the ‘Relative Age probably necessary. Effect’ - Possible Solutions: • Age on Date of Competition A number of suggestions have been made with Certainly in sports where performers respect to minimising the effect of relative age. These compete as an individual, eligibility should include: probably be based on ‘age on date of competition’. Therefore during a year Page 3 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

The Context future discussions by the ‘Sportsnation’ Panel. months of growth is unlikely to be significant, whereas in children and young people the changes that occur There are a wide variety of factors that can and do One factor that does seem to influence high-level in such a period can be huge. influence selection and progression in elite sport. The performance and which it might be possible to first step on the journey to high-level performance positively influence is termed the ‘relative age’ effect. As well as forming the basis for placing students in is participation, and it is well known that this is The relative age effect describes the observation school year groups the 12-month age bands also influenced by factors such as socio-economic status that greater numbers of performers born early in a form the basis for school sports team selection and and sex; with participation rates being greater among selection year are over-represented in junior and then perhaps selection to regional and national individuals in ‘professional’ occupations, and among senior elite squads compared with what might be teams. It should be noted that not all selection males (Rowe et al., 2004). In addition, while there is expected based on national birth rates. While the periods are 12-months in duration (some are longer), some variation between sports, it has been shown research evidence needs to be carefully interrogated and also that not all start in September (for example that children from lower socio-economic backgrounds it would appear that the relative age effect, certainly the international football year runs from January 1st to are less likely to reach high levels of sporting in some sports, crucially influences the opportunities December 31st ). achievement. The family background of potential for high-level sporting performance. This will be the high-level performers is also very important: families first topic for discussion by the ‘Sportsnation’ Panel. In general the distribution of births, namely the influence the entry of children into sport, provide numbers of children born in a particular month in practical, financial and emotional support, and it has England, is relatively uniform throughout the months Relative Age - Introduction: been observed that children from ‘one-parent’ families of the year. are less likely to progress into high-level sport (Kay, In England the school system is organized in 12- 2000). In addition, the structure of the families in month age bands such that all children and young which children and young people live and grow people born between the 1st September in a particular Relative Age - The educational evidence: is diverse and undergoing change over time (The year and the 31st of August of the following year are Lever Faberge Family Report 2004). This diversity In 1964 Jinks published a research paper describing educated together. By the end of “Year 8” all children of, and continual change in, family structure may how the academic performance of students’ on will be 13. However, within a particular year group create further problems for the progression of young an arithmetic test completed as part of their 11+ some individuals will have just turned 13 (those performers to elite sport. In addition, the elasticity of was influenced by their birth date. Among the 586 born in August) while others will be almost 14 (those family structure may mean that any solutions to this students placed in an ‘A’ stream as a result of the born in September). Therefore, there is almost a issue can only ever be temporary. These important test, 39% were born in September-December, 35% year’s difference in age and in potential growth and factors, and many others, may form the basis for in January-March and only 26% in May-August. It maturation and cognitive development. In adults 12 was also noted that the gap between streamed pupils Page 4 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

does not remain stable; in fact it seems to widen. Based on pilot Key Stage Maths and Science extends ultimately to the grades obtained at public While the reasons for this widening of differences Standard Assessment Tests (SATs) Giles (1993) examinations. While this effect may persist at in performance are not clear the effect of perceived found that autumn born pupils (September- University level in terms of the numbers of autumn success or failure on the attitude of the student, December) averaged half a level higher than students born students who graduate, in terms of performance and indeed on the attitude of the teacher could born in the summer (May-August). Giles (1993) (i.e. degree classification) it is summer born students be important. Jinks (1964) noted that while there suggested that sometimes the ‘slow learner’ may who do best. was little doubt regarding the reality of the relative just be among the youngest in their peer group and age effect, agreed solutions to minimize or negate may need an alternative form of encouragement and its impact were not available. Since these early support to that being presently offered. Relative Age - What is the evidence to observations by Jinks (1964) a number of other suggest it exists in sport? research studies have confirmed that month of birth However, by the time students reach degree level the influences scholastic achievements. effect of relative age may not be negative. Russell A number of published research studies have and Startup (1986) investigated the effect of month of investigated the relative age effect in sport (Boucher Thompson (1971), in his analysis of 1,136 boys who birth upon degree classification in 295,700 students and Mutimer, 1994, [Ice Hockey]; Brewer et al., entered a comprehensive school in Coventry during who undertook 3-year degrees between 1972-1982. 1995 [Football]; Dudink, 1994 [Football]; Edgar and 1955-64 and remained at the school for 5 years, While they did find that a disproportionate number O’Donoghue, 2005 [Tennis]; Musch and Hay, 1999 found that of the boys gaining 5 or more ‘O-level’ of students who were ‘older’ upon entry to University [Football]; Thompson et al.,1991 [Baseball]). The passes a greater proportion were born in the autumn actually graduated, the relatively youngest in a year results and findings from these studies have been term (September-December) than in the summer group were the ones who left with a better degree summarised in the figures in the following pages and term (May-August): 34% vs. 23% respectively. classification. A possible explanation for the findings in Appendix 1. Similarly, only 26% of boys born in the autumn term is that the relatively age disadvantaged summer born failed to gain any ‘O-level’ passes compared with students are those that have managed to overcome In addition, for the purposes of this report, further 40% born in the summer term. In addition, Thompson their disadvantage, and therefore relatively may be original data collection was undertaken (by the (1971) also found that the proportion of students in among the most academically able and successful in Institute of Youth Sport, Loughborough University) top and bottom streams in the school in their fourth their year group at University. to investigate whether the relative age effect year was also skewed: autumn born students were was evident in sports such as athletics, cricket, more likely to be in the top stream and summer born In summary, there is evidence in the literature that gymnastics, swimming and rugby union. This students in the bottom stream. the academic performance of students is influenced information has also been included in the analysis by the month of birth and that this influence presented in the following pages and in Appendix 1. Page 5 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Major League Baseballers (male) 1985 n=682 29% 27% 23% 21%

Baseball Evidence of a RELATIVE Major League Baseballers (male) 1990 AGE EFFECT? Yes n=837 29% Q1 Q2 Q3 Q4 Aug-Oct Nov-Jan Feb-Apr May-Jul 25% 23% 23% Source: Thompson et al., 1991

Evidence of a RELATIVE AGE EFFECT? Yes

Q1 Q2 Q3 Q4 Aug-Oct Nov-Jan Feb-Apr May-Jul Males

Source: Thompson et al., 1991 Page 6 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Junior Ice Hockey Players (male) 1988 / 1989 37% n=951 Males 28% 23%

12% Evidence of a RELATIVE AGE EFFECT? Yes NHL Ice Hockey Players (male) 1988 / 1989 Q1 Q2 Q3 Q4 34% n=884 Jan-Mar Apr-Jun Jul-Sep Oct-Dec 31% Source: Boucher & Mutimer, 1994

20% 15%

Evidence of a RELATIVE AGE EFFECT? Yes Ice

Q1 Q2 Q3 Q4 Hockey Jan-Mar Apr-Jun Jul-Sep Oct-Dec

Source: Boucher & Mutimer, 1994 Page 7 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

U20 Finalists English Schools Athletics Athletics (male) 45% 2002 n=130

Males 28% U15 Finalists English Schools Athletics (male) 17% 2002 9% 55% n=133 Evidence of a RELATIVE U17 Finalists English Schools AGE EFFECT? Yes Athletics (male) Evidence of a RELATIVE Q1 Q2 Q3 Q4 2002 AGE EFFECT? Yes 38% Sep-Nov Dec-Feb Mar-May Jun-Aug n=172 32% 23% Sources: http:www.esaa.net; Whittingham & Matthews 14% (Eds.) British Athletics Statistical Review 1999-2005 8% 17% 13% Q1 Q2 Q3 Q4 Sep-Nov Dec-Feb Mar-May Jun-Aug Evidence of a RELATIVE AGE EFFECT? Yes Sources: http:www.esaa.net; Whittingham & Matthews (Eds.) British Athletics Statistical Review 1999-2005 Q1 Q2 Q3 Q4 Sep-Nov Dec-Feb Mar-May Jun-Aug

Sources: http:www.esaa.net; Whittingham & Matthews (Eds.) British Athletics Statistical Review 1999-2005 Page 8 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Senior Athletes Ranked in Top 20 in their (ESAA) Event (male) 2002 34% n=340 Males 24% 21% 20%

Evidence of a RELATIVE AGE EFFECT? Yes Senior Athletes Ranked in Top 20 in their Event (male) Q1 Q2 Q3 Q4 Athletics 2002 Sep-Nov Dec-Feb Mar-May Jun-Aug 32% n=400 Source: Whittingham & Matthews (Eds.) British 24% Athletics Statistical Review 2002 23% 21%

Evidence of a RELATIVE AGE EFFECT? Yes

Q1 Q2 Q3 Q4 Sep-Nov Dec-Feb Mar-May Jun-Aug

Source: Whittingham & Matthews (Eds.) British Athletics Statistical Review 2002 Page 9 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’ English Professional 37% Footballers (male) 1991 / 1992 n=2777 FA School Footballers 25% (male) 6 year period 67% n=103 20% 19% Males Evidence of a RELATIVE Evidence of a RELATIVE AGE EFFECT? Yes AGE EFFECT? Yes

21% Q1 Q2 Q3 Q4 10% English Academy Footballers Sep-Nov Dec-Feb Mar-May Jun-Aug 2% (male) 2002 / 2004 Source: Dudink, 1994 Q1 Q2 Q3 Q4 n=1765 Sep-Nov Dec-Feb Mar-May Jun-Aug 48% Evidence of a RELATIVE Premiership Footballers Source: Brewer et al., 1995 AGE EFFECT? Yes (male) 2006 / 2007 25% 32% n=348 16% 11% 25% 24% Football 20%

Q1 Q2 Q3 Q4 Sep-Nov Dec-Feb Mar-May Jun-Aug Evidence of a RELATIVE AGE EFFECT? Yes Source: M. Hulse, The Football Association Medical and Exercise Science Department Q1 Q2 Q3 Q4 Sep-Nov Dec-Feb Mar-May Jun-Aug

Source: Premiership Clubs Websites Page 10 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

First Class County Cricketers (male) 2006 34% n=276 26% 22% 18% Premiership Rugby Union Players Males (male) 2006 / 2007 Evidence of a RELATIVE n=299 30% AGE EFFECT? Yes 27% 25% Q1 Q2 Q3 Q4 18% Sep-Nov Dec-Feb Mar-May Jun-Aug

Source: First Class Clubs Websites Evidence of a RELATIVE AGE EFFECT? Yes

Q1 Q2 Q3 Q4 Cricket Sep-Nov Dec-Feb Mar-May Jun-Aug

Source: Premiership Clubs Websites

Rugby Union Page 11 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Elite Judo Players (Seniors) Males (male) 2003-2006 n=172

26% 26% 23% 25% Judo Elite Judo Players (Juniors) 16-20 yrs (male) 2003-2006 n=93 32% Evidence of a RELATIVE 29% AGE EFFECT? No Elite Judo Players (Cadet) 12-16 yrs (male) 2003-2006 20% 18% Q1 Q2 Q3 Q4 n=367 Jan-Mar Apr-Jun Jul-Sep Oct-Dec 30% 27% 23% Evidence of a RELATIVE Source: John Bramall, British Judo Association 20% AGE EFFECT? No

Q1 Q2 Q3 Q4 Evidence of a RELATIVE Jan-Mar Apr-Jun Jul-Sep Oct-Dec AGE EFFECT? Yes Source: John Bramall, British Judo Association Q1 Q2 Q3 Q4 Jan-Mar Apr-Jun Jul-Sep Oct-Dec

Source: John Bramall, British Judo Association Page 12 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

ASA Age Championship 39% Swimmers (11-14 yrs) Senior International Swimmers (male) 2004 (male) 1986-2004 n=186 Males 28% n=96 35% 22% 30%

11% 21% Evidence of a RELATIVE AGE EFFECT? Yes 14%

ASA Youth Championship Evidence of a RELATIVE Q1 Q2 Q3 Q4 Swimmers (15-18 yrs) AGE EFFECT? Yes Aug-Oct Nov-Jan Feb-Apr May-Jul (male) 2004 33% Q1 Q2 Q3 Q4 Source: Amateur Swimming Association n=119 26% Jan-Mar Apr-Jun Jul-Sep Oct-Dec 23% 18% Source: Amateur Swimming Association Swimming Evidence of a RELATIVE AGE EFFECT? No

Q1 Q2 Q3 Q4 Aug-Oct Nov-Jan Feb-Apr May-Jul

Source: Amateur Swimming Association Page 13 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Elite Junior Tennis Players (male) 2003 Males 33% n=237 30% 22% 15%

Evidence of a RELATIVE AGE EFFECT? Yes Elite Senior Tennis Players (male) 2002 / 2003 Q1 Q2 Q3 Q4 n=237 Jan-Mar Apr-Jun Jul-Sep Oct-Dec 29% 29% 25% Source: Edgar and O'Donoghue, 2005 17%

Evidence of a RELATIVE AGE EFFECT? Yes

Q1 Q2 Q3 Q4 Tennis Jan-Mar Apr-Jun Jul-Sep Oct-Dec Source: Edgar and O'Donoghue, 2005 Page 14 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Athletics U20 Finalists English Schools Athletics (female) 2002 Females 37% n=133 U15 Finalists English Schools 28% Athletics (female) 23% 33% 2002 n=110 13% 25% 20% 22% U17 Finalists English Schools Evidence of a RELATIVE Athletics (female) AGE EFFECT? Yes 2002 Evidence of a RELATIVE n=156 Q1 Q2 Q3 Q4 28% 28% Sep-Nov Dec-Feb Mar-May Jun-Aug AGE EFFECT? No 24% 21% Sources: http:www.esaa.net; Whittingham & Matthews Q1 Q2 Q3 Q4 (Eds.) British Athletics Statistical Review 1999-2005 Sep-Nov Dec-Feb Mar-May Jun-Aug Evidence of a RELATIVE Sources: http:www.esaa.net; Whittingham & Matthews AGE EFFECT? No (Eds.) British Athletics Statistical Review 1999-2005

Q1 Q2 Q3 Q4 Sep-Nov Dec-Feb Mar-May Jun-Aug

Sources: http:www.esaa.net; Whittingham & Matthews (Eds.) British Athletics Statistical Review 1999-2005 Page 15 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Senior Athletes Ranked in Top 20 in their (ESAA) Event (female) 2002 n=320 31% 30% Females 20% 20%

Evidence of a RELATIVE AGE EFFECT? Yes Senior Athletes Ranked in Top Q1 Q2 Q3 Q4 20 in their Event (female) Sep-Nov Dec-Feb Mar-May Jun-Aug 2002 32% n=380 Source: Whittingham & Matthews (Eds.) British 30% Athletics Statistical Review 2002 19% 20%

Evidence of a RELATIVE AGE EFFECT? Yes

Athletics Q1 Q2 Q3 Q4 Sep-Nov Dec-Feb Mar-May Jun-Aug

Source: Whittingham & Matthews (Eds.) British Athletics Statistical Review 2002 Page 16 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

English International Footballers Gymnastics (U15-U21) (female) 2002 / 2004 n=113 Females Elite Gymnasts (Female) 27% 27% 2004 26% n=177 21% 29% 25% 26% 20% Evidence of a RELATIVE AGE EFFECT? No English Premiership Footballers (female) Evidence of a RELATIVE Q1 Q2 Q3 Q4 2004 / 2005 AGE EFFECT? No Jan-Mar Apr-Jun Jul-Sep Oct-Dec n=1537 26% 26% 26% Q1 Q2 Q3 Q4 Source: D. Scott, The Football Association 22% Jan-Mar Apr-Jun Jul-Sep Oct-Dec Medical and Exercise Science Department Source: J. Prescott, British Gymnastics

Evidence of a RELATIVE Football AGE EFFECT? No

Q1 Q2 Q3 Q4 Sep-Nov Apr-Jun Jul-Sep Oct-Dec

Source: D. Scott, The Football Association Medical and Exercise Science Department Page 17 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Elite Judo Players (Seniors) Females (female) 2003-2006 n=143 30% Judo 25% 24% Elite Judo Players (Juniors) 21% 16-20 yrs (female) 2003-2006 n=96 33% Evidence of a RELATIVE AGE EFFECT? No Elite Judo Players (Cadet) 12-16 yrs (female) 2003-2006 26% 24% n=281 Q1 Q2 Q3 Q4 30% 17% Jan-Mar Apr-Jun Jul-Sep Oct-Dec 26% 23% Source: John Bramall, British Judo Association 21% Evidence of a RELATIVE AGE EFFECT? No

Evidence of a RELATIVE Q1 Q2 Q3 Q4 AGE EFFECT? No Jan-Mar Apr-Jun Jul-Sep Oct-Dec

Q1 Q2 Q3 Q4 Source: John Bramall, British Judo Association Jan-Mar Apr-Jun Jul-Sep Oct-Dec

Source: John Bramall, British Judo Association Page 18 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

ASA Age Championship Swimmers (11-13 yrs) 45% (female) 2004 Senior International Swimmers n=145 (female) 1986-2004 Females n=95 26% 31% 27% 24% 16% 13% Evidence of a RELATIVE 16% AGE EFFECT? Yes Evidence of a RELATIVE Q1 Q2 Q3 Q4 ASA Youth Championship AGE EFFECT? No Aug-Oct Nov-Jan Feb-Apr May-Jul Swimmers (14-17 yrs) (female) 2004 Q1 Q2 Q3 Q4 Source: Amateur Swimming Association n=111 Jan-Mar Apr-Jun Jul-Sep Oct-Dec 26% 27% 27% Source: Amateur Swimming Association 20% Swimming Evidence of a RELATIVE AGE EFFECT? No

Q1 Q2 Q3 Q4 Aug-Oct Nov-Jan Feb-Apr May-Jul

Source: Amateur Swimming Association Page 19 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Elite Junior Tennis Players (female) 2003 Females 31% n=239 28% 25% 17% Elite Senior Tennis Players Evidence of a RELATIVE (female) 2002 / 2003 AGE EFFECT? Yes 33% n=211 28% Q1 Q2 Q3 Q4 Jan-Mar Apr-Jun Jul-Sep Oct-Dec 22% 17% Source: Edgar and O'Donoghue, 2005 Evidence of a RELATIVE AGE EFFECT? Yes

Q1 Q2 Q3 Q4 Tennis Jan-Mar Apr-Jun Jul-Sep Oct-Dec Source: Edgar and O'Donoghue, 2005 Page 20 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Summary of the research presented in the figures above which has investigated the “Relative Age Effect” in sport; √ = a relative age effect was found in the population group studied; X = no relative age effect was found in the population group studied.

Sport Sex Age Evidence of a Sport Sex Age Evidence of a Relative Age Effect Relative Age Effect Athletics Male Junior √ √ √ Athletics Female Junior X X √ Male Senior √ √ Female Senior √ √ Baseball Male Senior √ √ Cricket Male Senior √ Football Male Junior √ √ Football Female Junior X Male Senior √ √ Female Senior X

Gymnastics Female Elite X Ice Hockey Male Junior √ Male Senior √ Judo Male Junior √ X Judo Female Junior X X Male Senior X Female Senior X Rugby Union Male Senior √ Swimming Male Junior √ X Swimming Female Junior √ X Male Senior √ Female Senior X Tennis Male Junior √ Tennis Female Junior √ Male Senior √ Female Senior √ Page 21 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Relative Age - What is the evidence to effect is evident in many sports the exact mechanisms higher levels of competition. While the skills and suggest it exists in sport? (continued) through which it favours the older individuals remains self-confidence of the age-advantaged performer to be elucidated. develops, their age-disadvantaged peer may The figures and table above clearly demonstrate experience lack of opportunity, discouragement and that the relative age effect exists in a number of What is the cause of the relative age possibly disillusionment, perhaps eventually leading different sports. It is also clear that the relative age effect in sport? to dropout. effect is more prevalent among males than females. Interestingly, only in a weight classified sport such A large amount of research evidence demonstrates It should be noted that the research into the relative as Judo did the relative age effect not seem to be the existence of a relative age effect. However, little age effect typically limits its analysis to ‘chronological’ strong in males. The analysis also demonstrates of the research conclusively shows why this effect age. That is the actual age of the individual. However, that in many sports (for example athletics, baseball, exists. There appear to be a number of possible individuals will develop and mature (increase cricket, football, ice hockey, rugby union and tennis) reasons. It has been suggested that the relative age their functional ability to the point where they can the relative age effect persists into adulthood such effect occurs because, on the average, children and successfully procreate and rear offspring [Cameron, that senior players with a date of birth early in a young people with birth dates early in a selection 2002]) at differing rates. Differences in maturation, selection year are present in far greater numbers in period are those who are most likely to be more which are particularly evident during puberty, professional and senior leagues and competitions, mature and therefore stronger and faster and have mean that two young people can have exactly the and ranking lists, than would be expected based on more developed motor and co-ordination skills. As a same chronological age but, because they are national birth rates. result during selection trials they are the performers experiencing puberty at different times, have very most likely to catch the eye especially against age- different ‘biological’ ages. Because maturation affects The voluntary nature of sports participation compared disadvantaged peers. To compound the problem it physical function it obviously can have major impacts with the compulsory attendance required in education can be argued that talent selection procedures in (both positive and negative) on sports performance. may explain the persistence of the relative age many sports focus largely on physiological superiority. Therefore, biological age / maturation is also a key effect into adulthood in sport but not so obviously in Relatively younger individuals with equivalent or issue to be considered in talent identification and education. In other words while children must persist better technical, tactical and psychological skills development procedures. in education and hence may achieve success at a (which at the adult level may be the critical factors) later date, they may choose to drop out of a sport, may be overlooked as a result. In addition, as [Discussion continued on page 23] and therefore be lost to that sport, if they are not Thompson and colleagues (1991) note once an selected and deemed to be ‘unsuccessful’ at a young age-advantaged performer has been ‘selected’ they age. However, while the existence of a relative age are likely to be provided with better coaching and Page 22 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Relative Age - A hypothetical example an average boy. However, we can measure the when the boys reach adulthood there will be of the possible effect of relative age: height and weight of large numbers of children no differences in height and weight because (thousands) and from this calculate growth they are identical. However, if their physical Let us consider the effects of relative age in a curves, which give a reasonable indication of the characteristics in year 9 influenced selection to a simple theoretical way. In order to emphasise pattern of height or weight change that could be team (as is suggested in our theoretical example the potential impact of even 11 months worth expected in a child or young person at a certain described graphically in the figure below) it of growth let us consider an ‘average’ boy born age]. From the figure below we can see that is possible that Boy 2 would be deprived of on the 1st September 1990 (‘Boy 1’), and an the 11 months difference in chronological age chances given to Boy 1 simply because he was identical boy born 11 months later (‘Boy 2’). [Let results in substantial differences in height and born in August rather than 11 months earlier in us also recognise that there is no such thing as weight on the 1st September 2004. However, September.

Boy 2 is identical Entry to Year 9 Secondary School Selected Selected for Adult Characteristics Adult to Boy 1 1st September 2004 for School Professional Football except for Football Club Experience Relative Age being 11 Born Age Height Weight Team? Academy Age Height Weight Team? - A hypothetical months example of the younger. m

possible effect of c Professional m c Yes Yes 21 years 6 relative age: 1st September 14 years . player 'Boy 1' 4 7 . 7 1990 0 month 2 70.3 kg 1

The calculations are 6 49.2 kg 1 based on the British Growth Reference 1990 Dropped out

(revised Sept 1996) m of competitive c 1st August 13 years m c

'Boy 2' 4 assuming the Boy 1 (or . football at 15. No No 6 1991 5 21 years 1 month 43.4 kg X . 5 th 7 No longer 1 2) is on the 50 centile. 7 70.3 kg "Good player 1 plays football but too small" at all. Difference between boys at time indicated. 11 months 7.0 cm 5.7 kg 0 cm 0 kg Page 23 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Boucher and Mutimer (1994) argue that while other suggested that selection years should be performers capable of winning at senior authors offer a variety of reasons for the relative based on a period such as 9 months such level? These two aims may not always be age effect the underlying cause is actually an that each year different individuals in a compatible. That is not to say young people amalgamation of physical, cognitive, emotional, particular group will be age-advantaged. should not learn how to compete and be biological and sociological factors. Also, despite the However, such a system would be very exposed to competition. However, in the belief that differences in physical maturity explain demanding to administer and is perhaps an young, an over emphasis on competition, the relative age effect very few people have provided unrealistic option in most sports. competitive superiority, and the development evidence to support such an assertion. of an ethos of winning at all costs, which • Reduced Age Ranges: Age group squads replace the opportunity to train, to develop A number of issues relating to the relative age effect based on smaller age bands (6 months technique and improve skill may not create need to be clarified: Why does the relative age effect rather than 12 or 24) might alleviate some of the most appropriate environment in which to appear more evident in some sports than others? Are the effects of relative age. mould the young sports performers of today issues such as the type of sport and the size of the into the senior champions of tomorrow. competition field (i.e. the number of individuals who • Establish ‘Current’ and ‘Potential’ participate in the sport at particular representative Squads: The creation of 2 squads in a • Age on Date of Competition: Certainly levels) confounding factors? The point at which sports selection group rather than just one is a in sports where performers compete as start selecting for higher level performance squads is another suggested means of reducing an individual, eligibility should probably also likely to be a factor. The sex of the competitors the impact of relative age; one squad is be based on ‘age on date of competition’. may well be important with the relative age effect deliberately selected on potential rather than Therefore during a year different performers seemingly less evident in females involved in elite current ability and probably includes younger will be age-advantaged at different periods sport. performers who are technically proficient but during a year. A similar approach could be physically immature. used in team sports although the fact that teams are reliant on interaction between What to do about the ‘Relative Age Winning is not Everything!: An adjustment Effect’ - Possible Solutions: • individuals for success might make this of the “winning is everything focus” often difficult to implement. A number of suggestions have been made with evident in junior sport among performers, respect to minimising the effect of relative age: coaches, parents and others is probably • Altered Competition Structures: a move necessary. What is the purpose of junior away from a single national competition at • Rotating Cut-Off Dates: It has been elite sport: to win at junior level or to produce one time of year to a series of important Page 24 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

competitions spread throughout a year, child’s participation is heavily dependent on the ability References: where eligibility for participation is dependent of their family to accommodate the activity patterns on age on date of competition. Both required by the sport (Kay, 2000). Boucher, J.L. and Mutimer, B.T.P. (1994). The relative age phenomenon in sport: A replication and extension with Ice- individual and team sports could take this Hockey players. Research Quarterly for Exercise and Sport. approach. Simple factors such as geography can also play a part 65: 377-381.

in opportunity: poor access to facilities, such as a 50 Brewer, J., Balsom, P. and Davis, J. (1995). Seasonal birth m swimming pool, and poor access to coaches and distribution amongst European soccer players. Sports The influence of other factors on Exercise and Injury. 1: 154-157. sporting opportunity: high quality clubs are often a key impediment to the development of young performers. Cameron, N. (2002). Human growth curve, canalization, and catch-up growth. In: Human Growth and Development. Ed. It was noted at the beginning of this document that a Therefore it seems that a number of factors can and Noel Cameron. Academic Press. pp. 1-20. wide variety of factors can and do influence selection do influence the opportunities for high-level sporting Collins, M. (2004). Driving up participation: Soical exclusion. and progression in elite sport. Clearly the relative performance. It is also obvious that the greater the In: Driving Up Participation: The Challenge for Sport. Sport age effect is one such factor. However, it is not the England, April, 2004. number of barriers encountered by a young performer only factor which may influence the opportunities for the more difficult it will be for them to progress to Dudink, A. (1994). Birth date and sporting success. Nature high-level sporting performance. Collins (2004) has 368: 592. senior international level. argued that while factors such as physical location Edgar, S. and O’Donoghue, P. (2005). Season of birth and environment are important many individuals distribution of elite tennis players. Journal of Sports excluded from sport are poor (in terms of income). Acknowledgements: Sciences. 23: 1013-1020. Recently it has been estimated that the development Giles, R. (1993). The effect of date of birth on performance of an elite sports performer from child to adult will A number of individuals and organisations have within the secondary school. School Science Review. 75: 133-135. cost £250,000 over a 14 year period (Mike Turner, helped in the preparation of this report: Matt Jinks, P.C. (1964). An investigation into the effect of date personal communication). Clearly, such expenditure Sedgwick; Natalie Dunman; Mike Peyrebrune, of birth on subsequent school performance. Educational can only be afforded by certain individuals. Chelsea Warr and The Amateur Swimming Research. 6: 220-225. Association; Jo Prescott and British Gymnastics; Kay, T. (2000). Sporting excellence: A family affair? Interestingly it has also been shown that young Elizabeth Broomhead and the All England Netball European Physical Education Review. 6: 151-169. sportsmen and sportswomen who achieve high levels Association Ltd.; Dawn Scott, Mark Hulse and The Musch, J. and Hay, R. (1999). The relative age effect of performance are more likely to be from families Football Association Medical and Exercise Science in soccer: Cross-cultural evidence for a systematic drawn from the wealthier socio-economic classes Department; John Bramall and the British Judo discriminator against children born late in the competition (Yang et al., 1996). It has also been shown that a Association; year. Sociology of Sport Journal. 16: 54-64. Page 25 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Rowe, N., Adams, R. and Beasley, N. (2004). Driving up Yang, X, Telama, R. and Laasko, L. (1996). ‘Parents’ participation in sport: the social context, the trends, the physical activity, socio-economic status and education as prospects and the challenges. In: Driving Up Participation: predictors of physical activity and sport among children and The Challenge for Sport. Sport England, April, 2004. youths: a 12-year follow-up study. International Review of the Sociology of Sport. 31: 273-287. The Lever Faberge Family Report: Parenting under the microscope. (2004). Russell, R. J. H. and M. J. Startup. (1986) Month of birth and academic achievement. Personality and Individual Differences. 7: 839-846. Thompson, D. (1971). Season of birth and success in the secondary school. Educational Research. 14: 56-60.

Thompson, A.H., Barnsley, R.H. and Stebelsky, G. (1991). “Born to Play Ball” The relative age effect and major league baseball. Sociology of Sport Journal. 8: 146-151.

Whittingham, R. and Matthews, P. (2005). British Athletics 2005 (Statistical review of 2004 complied by the National Union of Track Statisticians). Umbra Athletics Limited.

Whittingham, R. and Matthews, P. (2004). British Athletics 2004 (Statistical review of 2003 complied by the National Union of Track Statisticians). Umbra Athletics Limited.

Whittingham, R. and Matthews, P. (2003). British Athletics 2003 (Statistical review of 2002 complied by the National Union of Track Statisticians). Umbra Athletics Limited.

Whittingham, R. and Matthews, P. (2002). British Athletics 2002 (Statistical review of 2001 complied by the National Union of Track Statisticians). Umbra Athletics Limited.

Whittingham, R. and Matthews, P. (2001). British Athletics 2001 (Statistical review of 2000 complied by the National Union of Track Statisticians). Umbra Athletics Limited.

Whittingham, R. and Matthews, P. (2000). British Athletics 2000 (Statistical review of 1999 complied by the National Union of Track Statisticians). Umbra Athletics Limited. Page 26 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Appendix 1: Summary of the research which has investigated the “Relative Age Effect” in Sport Sport Study authors Sex Subjects Subject Percentage of performers found in Selection Evidence Characteristics each quarter of the selection year Year Start Of Relative Date Age Effect Q 1 Q 2 Q 3 Q 4 Baseball Thompson et al. M Adults 1985: 682 major league 29 % 27 % 23 % 21 % 1st August Yes 1991 baseballers M Adults 1990: 837 major league 29 % 25 % 23 % 22 % 1st August Yes baseballers Ice Hockey Boucher & M Junior Players 1988-89 season: 951 37 % 28 % 23 % 12 % 1st January Yes Mutimer 1994 (8-17 years) players

M Adults 1988-89 season: 884 34 % 31 % 20 % 15 % 1st January Yes NHL players Athletics Morris et al., (IYS) M Adult 2002: 400 athletes UK 32 % 24 % 23 % 21 % 1st September Yes 2006 unpublished Top 20 in event M Adult 2002: 340 athletes UK 34 % 24 % 21 % 20 % 1st September Yes Top 20 in schools event M U20 2002: 130 English 45 % 28 % 17 % 9 % 1st September Yes Schools Finalists M U17 2002: 172 English 38 % 32 % 17 % 13 % 1st September Yes Schools Finalists M U15 2002: 133 English 55 % 23 % 14 % 8 % 1st September Yes Schools Finalists Cricket Morris et al., (IYS) M Senior 2006: 276 English 34 % 22% 26% 18% 1st September Yes 2006 unpublished First Class players Field Hockey Leslie et al., (IYS) M Senior 1993-95 & 2004: 21 19 % 24% 48% 10% 1st January No 2006 unpublished international players M Junior 1993-95: 48 40 % 19% 35% 6% 1st January No international players Page 27 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Judo Morris et al., (IYS) M Senior 2003-06: 172 Elite 26 % 26 % 23 % 25 % 1st January No 2006 unpublished Senior Internationals M 16-20 2003-06: 93 Elite 32 % 20 % 29 % 18 % 1st January No Players M 12-16 2003-06: 367 Elite 30 % 27 % 23 % 20 % 1st January Yes Players Rugby Union Morris et al., (IYS) M Senior 2006/2007: 299 30 % 27 % 25 % 18 % 1st September Yes 2006 unpublished Premiership players Swimming Dunman et al., (IYS) M Adult 1986-2004: 96 Senior 30 % 35 % 14 % 21 % 1st January Yes 2004 unpublished Internationals M 15-18 2004: 119 ASA Youth 18 % 26 % 23 % 33 % 1st August No Championship ‘Age on Date’ M 11-14 2004: 186 ASA Age 39 % 28 % 22 % 11 % 1st August Yes Championship ‘Age on Date’ Tennis Edgar & M Adult 2002/2003: 237 Grand 29 % 29 % 25 % 17 % 1st January Yes O’Donoghue 2005 Slam Entrants M Junior 2003: 237 Elite Junior 33 % 30 % 22 % 15 % 1st January Yes Men Football Dudink, 1994 M Adults 621 Dutch Professional 31 % 28 % 25 % 17 % 1st August Yes Football Players M Adults 1991-92: 2777 English 37 % 25 % 20 % 19 % 1st September Yes Professional Footballers Football Brewer et al., M Adults 16 Swedish Senior 50 % 19 % 19 % 13 % Not given Yes 1995 International Players M Junior 59 Swedish U17 58 % 20 % 20 % 2 % Not given Yes International Players M Junior 103 FA School Players 67 % 21 % 10 % 2 % 1st September Yes Page 28 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Appendix 1 (continued): Summary of the research which has investigated the “Relative Age Effect” in Sport Sport Study authors Sex Subjects Subject Percentage of performers found in Selection Year Evidence Characteristics each quarter of the selection year Start Date Of Relative Age Effect Q 1 Q 2 Q 3 Q 4 Football Musch & Hay M Adults 1995-96: 355 German ~32 % ~25 % ~22 % ~23 % 1st August Yes 1999 Professional Footballers M Adults 1995-96: 486 Brazilian ~30 % ~27 % ~25 % ~19 % 1st August Yes Professional Footballers M Adults 1995-96: 360 Japanese ~37 % ~30 % ~17 % ~18 % 1st April Yes Professional Footballers M Adults 1988-89: 207Australian ~31 % ~27 % ~25 % ~18 % 1st January Yes Professional Footballers M Adults 1995-96: 61 Australian ~38 % ~22 % ~20 % ~22 % 1st August Uncertain Professional Footballers Weak Football Hulse et al., (IYS) M Adults 2004-05: 277 Premiership 35 % 27 % 21 % 16 % 1st September Yes 2005 unpublished Footballers M Junior 2002-04: 1765 English 48 % 25 % 16 % 11 % 1st September Yes (8-18) Academy Footballers Football Hulse et al., (IYS) M Adults 2006-07: 348 Premiership 32 % 25 % 24 % 20 % 1st September Yes 2006 unpublished Footballers Athletics Morris et al., (IYS) F Adult 2002: 380 athletes UK Top 30 % 32 % 19 % 20 % 1st September Yes 2006 unpublished 20 in event F Adult 2002: 320 athletes UK Top 31 % 30 % 20 % 20 % 1st September No 20 in schools event F U20 2002: 133 English Schools 37 % 28 % 23 % 13 % 1st September Yes Finalists F U17 2002: 156 English Schools 28 % 28 % 24 % 21 % 1st September No Finalists F U15 2002: 110 English Schools 33 % 25 % 20 % 22 % 1st September No Finalists Page 29 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

F 12-16 2003-06: 281 Elite Players 26 % 30 % 23 % 21 % 1st January No

Netball Morris et al., (IYS) F 18-Senior 1999-2004: 209 Elite 28 % 20 % 27 % 24 % 1st January No 2004 unpublished Netball Players Swimming Dunman et al., (IYS) F Senior 1986-2004: 95 Senior 31 % 27 % 16 % 24 % 1st January No 2004 unpublished Internationals F 14-17 2004: 111 ASA Youth 26 % 27 % 27 % 20 % 1st August No Championship ‘Age on Date’ F 11-13 2004: 145 ASA Age 45 % 26 % 16 % 13 % 1st August Yes Championship ‘Age on Date’ Tennis Edgar & F Adult 2002/2003: 211 Grand 33 % 28 % 22 % 17 % 1st January Yes O’Donoghue 2005 Slam Entrants F Junior 2003: 239 Elite Junior 31 % 25 % 28 % 17 % 1st January Yes Women Page 30 Enhancing opportunities for high-level sporting performance: influence of ‘Relative Age’

Appendix 2 1.) 11-15 yr olds in UK population 2005 HYPOTHETICAL IMPACT OF THE RELATIVE AGE EFFECT IN SPORT: 3,895,000 males females 1. Number of 11-15 year olds in the UK 1,998,000 1,897,000 population:

[based on Statistics in Education: Education and Training Statistics for the United Kingdom 2005 Edition, London:TSO] 2.) distribution of population by birth date - assuming an even distribution

Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 2. Distribution of 11-15 year olds in the UK e.g. Sep-Nov e.g. Dec-Feb e.g. Mar-May e.g. Jun-Aug e.g. Sep-Nov e.g. Dec-Feb e.g. Mar-May e.g. Jun-Aug population by Birth Date: OR Jan-Mar OR Apr-Jun OR Jul-Sep OR Oct-Dec OR Jan-Mar OR Apr-Jun OR Jul-Sep OR Oct-Dec [assuming an even distribution of births] 499,500 499,500 499,500 499,500 474,250 474,250 474,250 474,250

3. Assume that the top 10% of 11-15 year olds in the UK population form a hypothetical 3.) distribution of birth dates in a gifted and talented cohort (Top 10%) - assuming an even distribution 'gifted and talented' in PE and Sport cohort.

Therefore, the expected distribution of 'gifted and talented' performer numbers by Birth Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Date would be [assuming an even distribution of 49,950 49,950 49,950 49,950 47,425 47,425 47,425 47,425 births]:

4. Research suggests that often birth date 4.) in sport birth distributions are often uneven - fewer performers with birth dates in Q4 distributions are not even in sport.

Let us assume that the distribution of births for this hypothetical gifted and talented Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 cohort resembles that seen in the research 69,930 49,950 49,950 29,970 56,910 47,425 47,425 37,940 literature. Therefore, the distribution of performers by birth date might be: 5. HYPOTHETICAL IMPACT OF THE RELATIVE AGE EFFECT IN SPORT: males: Q1-35%; Q2-25%; Q3-25%; Q4-15% Therefore, this hypothetical example suggests that potentially 20,000 boys and 10,000 girls might not females: Q1-30%; Q2-25%; Q3-25%; Q4-20% be selected on the basis of their age / birth date.