Does Junior Performance Predict Senior Performance in Olympic Sports?
Summary of a systematic review and meta-analysis
This blog provides a summary of a recent research paper for those who are interested in youth athletic development and understanding the science of predicting future champions.
It comes at the perfect time as the 2024 Olympic Games are upon us.
I am going to simply report a bit of the methods (how they did the study) and the key findings, while trying to simply explain the research methods and statistics for the non-science folks (but will include some of the statistical gobbly-gook).
Rationale for the Study
Quite simply, a lot of people are interested in predicting and identifying young athletes who may become future stars. But, does performance as a youngster predict performance as an adult athlete? Does the best 9-yr old 800-m runner become an Olympian?
Methods: How they did the study
This study is called a systematic review and meta-analysis. Think of it this way - 50 researchers from around the world all do single, independent studies examining if success as a young athlete predicts success as an adult athlete. A few years later, another researcher (or maybe one of the 50) collects all 50 of the single, independent research studies described and pools the results. A comprehensive statistic is calculated to represent all 50 studies - because more than likely they did not all result in the exact same result. So, instead of relying on the results of one or a few studies (cherry-picking the best results that may suit your cognitive bias!), we get a meta-statistic that represents the entirety of all the studies. Think of it as the “average of the averages”. [Click here for a 3-min animated video explaining meta-analysis]
In this systematic review and meta-analysis, 129 research results from a grand total of 13,392 athletes (62% male and 38% female) from a wide range of Olympic sports were analysed. In addition, the quality of the studies is graded and the authors reported that the quality of studies was high. (Note: just because an original study is published does not mean that it’s necessary a good study. Some published studies are quite flawed. Don’t ask …. maybe another time.)
Results: What did they find?
The authors reported the following key findings.
1. The pooled correlation statistic between junior and senior performance was 𝑟⎯⎯ = 0.148 ( r = 1.0 is a perfect correlation, thus 0.15 is weak). That is, junior performance explained only 2.2% of variance in senior performance. If the correlation (r) was 0.80, fairly strong, then it would explain 64% (square the r value to get the %) of the variance. Not bad but still leaves 36% of variance unexplained and due to other factors.
2. The finding (a weak relationship) was robust across types of sports, sexes, wider or narrower performance ranges, national or international samples, and performance measures. Thus, it was also a consistent finding.
3. Effects did vary across age categories: the younger the junior age category, the lower the correlation between junior and senior performance - that is, the further away from senior performance the less predictive ... kinda like trying to forecast the weather🌧️ 2-weeks out!
Headline: Junior performance has very little, if any, predictive value for senior performance.
As concluded by the authors …. “The findings run counter to claims from traditional theories of both giftedness and expertise. From an applied perspective, talent selection typically begins around puberty or younger—age ranges where youth performance is uncorrelated or negatively correlated with later senior performance. The evidence presented here raises serious questions about the use of junior performance for talent selection purposes.”
Implications: Keep as many in the pipeline for as long as possible.
For those interested in the full research paper by Barth and colleagues published in the journal Sports Medicine click here
Related content from IronMan Performance here:
The Tyranny of Talent - excerpts from Dr. Joe Baker's book on talent ID and youth athletic development
Tracking Hurricanes & the Stock Market and the Prediction of Future Athletes - a long-form blog providing a more detailed discussion about the science
The Influence of Maturation on Physical Performance during Adolescence - a 20-min video lecture
Brilliant summary and also thanks for the r=% square rule! As also a grassroots coach, I wish this weak correlation would better inform youth sports culture.