Predicting future stars: Probability and performance corridors for elite swimmers

What It Takes to Win: Examining Predicted Versus Actual Swimming Performances at the Paris 2024 Olympic Games, and What Comes Next

Predictions of performances should be evaluated to confirm their accuracy. Work by this group has resulted in 3 sets of predictions being generated for swimming events at the Paris 2024 Olympic Games, using the same statistical approach for each set.

PURPOSE

To examine the accuracy of swimming predictions for the Paris 2024 Olympic Games and generate updated predictions for both the Singapore 2025 World Aquatics Championships and Los Angeles 2028 Olympic Games.

METHODS

A linear regression and forecasting function was used to generate predictions for the Paris 2024 Olympic Games across 3 performance categories (rank 1st-3rd, 4th-8th, and 9th-16th). Mean absolute error was used to assess the accuracy of the predicted versus actual Paris 2024 Olympic Games times for all events across the 3 performance categories. New predictions for the 2028 Olympic cycle were subsequently generated using results from the World Championships and Olympic Games between 2011 and 2024.

RESULTS

Across all events, a mean absolute error value of 0.84% was observed between the Paris 2024 Olympic Games predicted and actual times. Predicted times were highly correlated with actual times (r2 = .99). Across the 3 sets of predictions (created in 2022, 2023, and 2024), the 2023 set of predictions had the lowest overall mean absolute error value (0.55%).

CONCLUSIONS

The methods used to create predictions for swimming performances at the Paris 2024 Olympic Games were deemed accurate. These methods enable national swimming federations to create a series of predictions for a given major championship, inform athlete identification and development pathways, and allocate appropriate resources, including sport-science provision.

Focus on One Swimming Stroke or Compete in Multiple: How Much Specialization Is Needed to Become a World-Class Female Swimmer?

Objectives: To investigate performance development and variety in swimming strokes of female swimmers from early junior to elite age. Methods: A total of 194,788 race times of female 200 m swimmers representing 77 nations were ranked at peak performance age and clustered into world-class finalists (>850 swimming points), international-class (750-850), national-class (650-750) and regional-class swimmers (550-650). Annual best times for each swimming stroke were retrospectively extracted throughout adolescence from 13 years of age. Longitudinal performance development and differences between the swimmers' main and their secondary swimming strokes were analyzed using linear mixed model. Results: World-class freestyle swimmers show significantly (p ≤ 0.042) higher swimming points across all age categories compared to international-, national- and regional-class swimmers. Linear mixed model analysis indicates a significant performance progression for international- and national-class freestyle swimmers up to the 19-20-year-old category (p ≤ 0.038), but an earlier plateau was observed for regional-class swimmers (p = 0.714). Comparing main and secondary swimming strokes, freestyle swimmers show the highest degree of specialization. For breaststroke and individual medleys, specialization increases with increasing performance level and the closer an athlete is to elite age. World-class butterfly and backstroke finalists show the lowest specializations in terms of the smallest number of significant differences compared to performances in their secondary swimming strokes. Conclusions: Higher ranked swimmers show a greater degree of specialization. As different specialization patterns are evident for the various swimming strokes, decision makers and talent specialists should align development guidelines accordingly and base them on the most advantageous combinations of swimming strokes.

Quantity of within-sport distance variety - what can pool swimmers and track runners learn from each other?

Objective

To determine the relationship between success at peak performance age and quantity of within-sport distance variety and compare the dose-time-effect between swimming and track running by determining probability of becoming an international-class female athlete based on the number of different race distances the athletes compete in each year throughout their development process.

Methods

Race times of female Tier 2 to Tier 5 freestyle pool swimmers (n = 2,778) and track runners (n = 9,945) were included in the present study. All athletes were ranked according to their personal best at peak performance age. Subsequently, number of different race distances during each year were retrospectively extracted from peak performance to early junior age. Personal best performance points at peak performance age were correlated with the number of different race distances across the various age categories. Poisson distribution determined the dose-time-effect of becoming an international-class athlete based on the number of different swimming strokes.

Results

At peak performance age, correlation analysis showed a larger within-sport distance variety for higher ranked athletes, particularly for track runners (r ≤ 0.35, P < 0.001). Despite reaching statistical significance, the effects were small to moderate. While swimmers showed a generally larger within-sport distance variety than track runners, Poisson distribution revealed a dose-time-effect for the probability of becoming an international-class swimmer. Sprint and middle-distance swimmers benefit from competing in three race distances during junior age and a transition to two race distances at 17-18, 18-19, 20-21 and 25-26 years of age for 50 m, 100 m, 200 m and 400 m races, respectively. Long-distance swimmers should maintain three different race distances throughout peak performance age. Probability analysis showed a consistent benefit of competing in one or two race distances for 100 m, 200 m, 400 m and 800 m track runners.

Conclusion

Within-sport distance variety is not a continuum but an ever-evolving process throughout the athletes' careers. While swimmers generally show larger variety than track runners, the progressive specialization towards peak performance age improves success chances to become an international-class swimmer.

Participation but not success in youth and junior World Championships is important for overall ranking in the biathlon World Cup during adult age

Purpose

The aim of this study was to investigate if competition rank in the youth (16-19 years) and junior (20-22 years) World Championships (WCH) and age of the athlete when reaching certain World Cup (WC) performance milestones (debut and top 40, 15, 6 and 3) were related to future World Cup total (WCT) performance.

Methods

All data was obtained from the International Biathlon Unions database. The biathletes ranked top 30 in the WCT (82 men, 98 women) during 10 consecutive competition seasons were selected for further analysis. Biathletes were divided into performance groups due to their best WCT ranking (WCT6, rank 1-6; WCT15, rank 7-15; WCT30, rank 16-30). The relation between youth and junior WCH ranking and age when reaching the WC performance milestones with WCT performance was investigated.

Results

63.3% and 86.1% of the biathletes in the WCT top 30 competed in the youth and/or junior WCH, respectively, but the correlation between junior and senior ranking was low. WCT6 reached most of the WC performance milestones at a younger age compared to WCT15 and WCT30 (p > 0.05) and reaching WC top15 at a younger age increased the chance of reaching WCT6 in the future.

Conclusion

It seems beneficial to compete internationally (i.e., participation in youth/junior WCH) and reach certain WC performance milestones at a young age to achieve a high ranking in the WCT during adult age. This highlights that biathletes need to have a certain performance level during junior years, although ranking in youth/junior WCH is not a prediction for senior WCT success.

Relative Age Effects and Place of Early Development Constrain Male Youth Italian Swimmers' Developmental Experiences

Italian swimming emphasizes the early specialization of selected children from approximately 6 to 7 years old. Such an approach often leads to selection biases (i.e., birth advantages), which may undermine swimmers' development and progression through the talent pathway. Accordingly, this study aimed to: (a) explore the presence of birth advantages at the annual Italian national age-group competition by observing the birth quarter (BQ) and place of early development (PED) distribution of 514 U15 swimmers; and (b) investigate how birth advantages affect swimmers' ability to maintain their national status by comparing the BQ and PED distributions of 555 U17 national-level swimmers to the expected values (i.e., U15 distribution). Chi-square statistics for the U15 revealed an overrepresentation of BQ1s and swimmers developing in north and central Italy (p-values < 0.0001). In contrast, the U17's BQ (p < 0.001) and PED (p = 0.01) distributions appeared skewed compared to the U15, favoring swimmers born in BQ3 and BQ4, and swimmers developing in north Italy (odds ratios: 1.69, 1.76, 1.39 respectively). The findings highlighted that cultural-contextual features of the environment shape Italian youth swimmers' development and their progression through the current talent pathway.

Performance pathways in elite middle- and long-distance track and field athletes: The influence of a successful youth

OBJECTIVES

There is limited information on the performance progression of athletics endurance athletes from junior-to-senior status and the determinants of success in adulthood. This study aimed to quantify the youth-to-senior transition rate, the likelihood of success and the relationship between youth and senior performance amongst world-class athletes competing in middle- and long-distance disciplines.

DESIGN

Retrospective design examining public data between 2000 and 2019.

METHODS

The performances of 4678 international athletes (45.3 % female) were analysed. World's all-time top 50 athletes were identified for U18 and Senior categories (age ≥ 20 years). Youth-to-senior transition rate and transition probabilities were calculated. Correlations between best U18 and Senior performances were determined to assess the stability of the performance.

RESULTS

The youth-to-senior transition rate for top U18 athletes was low for males and females (~19 % and 21 %). Nevertheless, the probability of transition to a top senior was ~7 times higher for top U18 athletes than for non-top U18 athletes. The correlations between youth and senior best performances were low-to-high.

CONCLUSIONS

Few top U18 athletes maintained top world ranking status during their senior careers. Still, they are more likely to become top senior athletes than those who did not perform at the top level in U18. The association between youth and senior performance is stronger when comparing the same discipline or when athletes competed over longer distances in their senior compared to U18 career. Being a successful youth athlete may represent a small advantage for future success, however, it does not guarantee advancement to the senior top level.