Chronological Age and its Relation to Results of Tokyo Olympic Games 2020 as a Basis for Preparing Female Judokas for Olympic Participation

: Aim : to analyze data and results of female judokas in Tokyo Olympics 2020 to identify the chronological age of younger / older judokas and its relation with results in all the seven weight categories in the Olympic Games. Methods : The researchers used the descriptive (survey) approach. Research community included data and results of female judokas (n=192) who participated in Tokyo Olympic Games 2020, held from 24 to 31 July 2021, representing (128) countries in (5) continents. Researchers used female judokas dates of birth and “DATEDIF” equation in “Microsoft Excel” to calculate chronological age of female judokas (day – month – year) on January 1 st 2020. Results : younger judokas won (118) matches (55.40%) on the following weight categories: (-48) kg (58.06%) – (-52) kg (62.50%) – (-57) kg (53.57%) – (-70) kg (74.07%) – (+78) kg (66.67%). Older judokas won (95) matches (44.60%) on (-63) kg weight category (61.67%). Chi2 results indicated statistically significant correlation between age and results on P ≤0.05 in favor of younger judokas on (-48 kg - -54 kg - - 70 kg - +78 kg) weight categories. Another statistically significant correlation between age and results on P ≤0.05 in favor of older judokas was shown for (-63) kg age category. No statistically significant correlation between age and results was shown for neither older no younger judokas on (-57) and (-78) kg weight categories. The researchers concluded that the mean age of younger judokas in the four weight categories (-48, -52, -70, +78) kg was (23.10) year/month and (26) days while the same value for older judokas on (-63) kg weight category was (28.11) year/month and (16) days. The researchers concluded that the best chronological age for peak competitive performance and best results was approximately (23.10) year/month. Therefore, the start of long-term planning process for Olympic participation should start at the age of (19). The chronological age for first Olympic participation should be revised to preserve the healthy development of musculoskeletal system and improving technical and tactical aspects required for elite competitive levels. This may also decrease early competitive pressure over athletes that may affect their physical and mental health negatively.


Introduction:
Among other factors including physical, technical, and mental aspects, chronological age is a major factor in selecting elite female judokas to be prepared for Olympic Games, as age differs among judokas chosen for the Olympics in case, we neglect choosing them on the basis of chronological age suitable for peak performance necessary for achieving Olympic medals.In general, Olympic Games are the best example that summarizes results of years of training and details of advances in technical and tactical performance among judokas.Therefore, it should be studied to identify current requirements and challenges that coaches and athletes should make use of to improve performance and achieve advance (Ghazy et al. 2023).
The twenty third Olympic Games (Tokyo 2020), held in July 2021, reminds us with the importance of following competition rules and fair play that characterize Olympic athletes.Athletic competitions are the oldest form of playing and winning as each athlete needs to master good technical and mental performance to achieve best results.This is what elite athletes do during pre-competition technical, physical and mental preparation (Schijven & Kikkawa 2021).
As for Tokyo Olympic 2020, only athletes committed to the Olympic Covenant had the right to qualify as qualification for the Olympics necessitates full commitment with the Olympic Covenant rules like, for example, rule no.41 (competitors' nationality) and rule no.43 (the antidoping international rule and the Olympic movement rule for preventing competition manipulation).All judokas qualified for Tokyo Olympics had to be born at or before December 31 st 2006 (IJF 2021).This means that qualified judokas had to be at least ( 15 Pushing young judokas to participate in national and international competitions, along with older judokas from higher age categories, and facing opponents who are older than them by 2-6 years may provide them with various experiences and develop them competitively to wing medals.But this training approach, depending on long competitive preparation, may have negative effects on their future results in addition to increasing young athletes' drop-out.Therefore, coaches should concentrate on preparing young judokas for international championships through participation in national and international competitions according to their age category.This ensures normal evolution of the musculoskeletal system of those young athletes and assures stable advances in technical and tactical aspects required for elite competitions (Simenko 2022).
Accordingly, it is clear that winning Olympic medals can be achieved with the combination of all factors participating in successful preparation of female judokas for Olympic tournaments.This starts with long-term and science-based planning.The researchers think that identifying the suitable chronological age is a major factor for starting judokas' preparation for Olympic tournaments as it contributes in successful longterm planning.A few studies dealt with effects of chronological age in judo on winning chances of older and younger judokas, the suitable age for achieving peak performance and results for female judokas and the relationship between age and winning results as a basis for good selection and long-term planning for participation in the Olympics.This led the researchers to perform this study.

Aim:
This study aimed at analyzing data and results of female judokas in Tokyo Olympics 2020 to identify the chronological age of younger / older judokas and its relation with results in all the seven weight categories in the Olympic Games.
What is the mean ages of winner female judokas in the seven weight categories in Tokyo Olympic Games 2020? 2.
What is the relationship between chronological ages of younger/older female judokas and results of Tokyo Olympic Games 2020 the seven weight categories?Methods: Approach: The researchers used the descriptive (survey) approach.

Match = Order of match on Scoresheet
Table (4) indicated that ages of female judokas in some matches were very close as it does not exceed 7 days as minimum difference and 9 months and 4 days as maximum difference.5) indicated statistically significant differences in the number of winning matches among older and younger female judokas in favor of younger judokas on four weight categories (-48, -54, -70 and +78) as chi 2 values were significant on p ≤ 0.05.this indicates a positive correlation between younger age and results as the least the age the better the results of female judokas in tokyo olympics 2020 in these weight categories.statistically significant differences on (-63) kg weight category were in favor of older female judokas as chi 2 values were significant on p ≤ 0.05.this indicates a positive correlation between younger age and results as the least the age the better the results of female judokas in tokyo olympics 2020 in this weight category.as for (-57) and (-78) kg weight categories, there were no statistically significant differences between the results of younger and older female judokas as frequency and percentages of winning came once in favor of younger judokas on (-57) weight category and anther in favor of older judokas on (-78) kg weight category.discussion: tables (3), ( 4) and ( 5) indicated that number of females matches in judo was (213) matches.number of matches won by older judokas was (95) (44.60%) while number of won matches by younger judokas was (118) (55.40%).number of matches won by judokas against opponents of the same birth year was (13). the following is detailed analysis of results for each weight category: (-48) kg weight category: younger judokas won (18) matches (58.06%) while older judokas won (13) matches (41.94%) out of (31) matches in this weight category.chi 2 value (0.806) was significant on p ≤ 0.01.these results indicated that younger and more talented judokas vectored older and more experienced opponents except for three matches as the two opponents were born in the same year: in match number (1), chibana gabriela (brazil) vectored the older bonface harriet (malawi) with difference in age approximately (6) months and (11) days and in match number ( 16), the older rishony shira (israel) vectored the younger figueroa julia (spain) with difference in age approximately (1) month and ( 12) days.in match number (35) (final), the younger krasniqi distria (kosovo) vectored the older tonaki funa (japan) with difference in age approximately (4) months and (9) days.
(-52) kg weight category: younger judokas won (20) matches (62.50%) while older judokas won ( 12) matches (37.50%) out of (32) matches in this weight category.chi 2 value (2.001) was significant on p ≤ 0.01.these results indicated that younger and more talented judokas vectored older and more experienced opponents except for two matches as the two opponents were born in the same year: in match number (13), cohen gili (israel) vectored the older babamuratova gulbadam (turkmenistan) with difference in age approximately (2) months and (5) days and in match number (24), the younger pupp reka (hungary) vectored the older park da-sol (republic of korea) with difference in age approximately (5) months and (5) days.
(-57) kg weight category: younger judokas won (15) matches (53.570%) while older judokas won (13) matches (46.43%) out of (28) matches in this weight category.chi 2 value (0.134) was non-significant.these results indicated that younger and more talented judokas vectored older and more experienced opponents except for one match as the two opponents were born in the same year: in match number ( 16), older gjakova nora (kosovo) vectored the younger verhagen sanne (netherlands) with difference in age of only one week.
(-63) kg weight category: older judokas won ( 21) matches (61.76%) while younger judokas won ( 13) matches (38.24%) out of (34) matches in this weight category.chi 2 value (1.882) was significant on p ≤ 0.01.these results indicated that older and more experienced judokas vectored younger and more talented judokas except for three matches as the two opponents were born in the same year: in match number (13), the older ozobablach agata (poland) vectored the younger garcia estefania (equador) with difference in age approximately (2) months and (6) days and in match number (18), the younger beaucheminpinard catherine (canada) vectored the older krssakova magdalena (austria) with difference in age approximately (3) months and ( 23) days.in match number (6) the older quadros ketleyn (brazil) vectored the younger david cergia (hondoras) by withdrawal as the later didn't pass the official weight and didn't get a rank in this competition.
(-70) kg weight category: younger judokas won (20) matches (64.52%) while older judokas won (11) matches (35.48%) out of (31) matches in this weight category.chi 2 value (2.613) was significant on p ≤ 0.01.these results indicated that younger and more talented judokas vectored older and more experienced opponents except for two matches as the two opponents were born in the same year: in match number (1), the younger matniyazova gulnoza (uzbekistan) vectored the older memneloum demos (chad) with difference in age approximately (4) months and in match number (11), the younger scoccimaparo giovanna (germany) vectored the older rodriguez elvismar (venezuela) with difference in age approximately (9) months and (4) days.
(-78) kg weight category: older judokas won ( 15) matches (55.56%) while younger judokas won ( 12) matches (44.44%) out of ( 27) matches in this weight category.chi 2 value (0.333) was non-significant.these results indicated that older and more experienced judokas vectored younger and more talented judokas except for one match as the two opponents were born in the same year: in match number (2), the younger prodan karla (croatia) vectored the older pekovic jovana (montenegro) with difference in age approximately (7) months and (13) days.
(+78) kg weight category: younger judokas won (20) matches (66.67%) while older judokas won ( 10) matches (33.33%) out of (30) matches in this weight category.chi 2 value (3.333) was significant on p ≤ 0.05.these results indicated that younger and more talented judokas vectored older and more experienced opponents except for two matches as the two opponents were born in the same year: in match number (12), the younger ortiz idalys (cuba) vectored the older nunes rochele (portugal) with difference in age approximately (3) months and (8) days and in match number ( 16), the younger kindzerska iryna (azerbaijan) vectored the older ceric larisa (bosnia and herzegovina) with difference in age approximately (4) months and (9) days.

conclusions:
according to analysis of birth dates for (192) female judokas and their results of ( 213) matches in tokyo olympics 2020 through extracting frequency and percentages (winning/losing) for older and younger judokas for each match, results indicated that average age of younger judokas was (23 years -6 months -26 days) while average age for older judokas was (28 years -2 months -20 days).
chi 2 results indicated statistically significant correlations on p ≤ 0.05 for the following weight categories: (-48 kg --54 kg --70 kg -+78 kg) in favor of younger judokas.this means a negative correlation as the younger the judoka the better the results.average age for this age category was (23 years -6 months -26 days).the researchers think that this correlation in favor of younger judokas in tokyo olympics in these weight categories indicates that these judokas are in a suitable age for winning as their mean age was (23 years -10 months -26 days).this age represented the peak of maturity of physical and technical qualities required for winning.on the contrary, the average age for older judokas was (28 years -1 month -18 days) and mean age was (28 years -6 months -19 days).this increase in mean age led to a decrease in judokas' physical abilities required in these weight categories and this increases the chances of winning in favor of younger judokas.
there is a positive correlation between age and results in (-63) kg weight category as the correlation was statistically significant on p ≤ 0.05 in favor of older judokas.this means the older the judoka the better the results.average age for this weight category was (28 years -11 months -16 days).the researchers think that this correlation is due to the older age of younger judokas as they were younger with only two years in comparison with other weight categories with mean age (24 years -9 months -3 days).this led to a decrease in their physical and technical qualities and affected their results negatively.
there was no correlation between age and results neither for older nor for younger judokas on two weight categories (-57 kg and -78 kg).average age for older judokas was (27 years -11 months -20 days) while the average age for younger judokas was (22 years -11 months -2 days) in those weight categories.the researchers think that this is due to the non-significance of chi 2 value for winning in younger judokas in (-57kg) weight group although they were superior in percentages and frequency of winning.but their mean age was less by two years compared with their counterparts in other weight categories.their mean age was (21 years -10 months -26 days).younger judokas played ( 17