Andrew C. Cornett

Large N: a strategy for improving regional sport performance.

UNLABELLED It has been hypothesized that large differences in maximal performance can arise between various geopolitical regions solely on the basis of differing numbers of participants in the target activity. While there is evidence in support of this hypothesis for a measure of intellectual performance, the same relationship has not been examined for a measure of physical performance. PURPOSE To determine whether the number of participants is a predictor of the best athletic performance in a region. METHODS The 2005-2010 USA Swimming Age Group Detail reports were used to determine the number of competitive swimmers participating in each age group for the 59 local swimming communities in the United States. The USA Swimming performance database provided 50-yd-freestyle times in each community for boys and girls for each age (6-19 y). Simple linear regression was used to examine the relationship between the outcome variable (fastest time) and the predictor variable (log of the number of swimmers) for each combination of age, sex, and calendar year. RESULTS The log of the number of swimmers in a region was a significant predictor of the best performance in that region for all 168 combinations of age, sex, and calendar year (P<.05) and explained, on average, 41%, and as much as 62%, of the variance in the fastest time. CONCLUSION These findings have important implications for the development of regional sport strategic policy. Increasing the number of participants in the target activity appears a viable strategy for improving regional performance.

Lane bias in elite-level swimming competition

ABSTRACT Performance outcomes at the 2013 World Swimming Championship were previously shown to be biased depending on the swimmer’s lane assignment. The purpose of this study was to determine if this kind of bias was unique, and if not, if the bias was related to the temporary or permanent nature of the pool. The effect of lane on the average odd-length split minus the preceding even-length split in the 800- and 1500-m freestyle events, and on the relative change from qualifying to preliminary performance in the 50-m events, was determined for 16 other elite-level competitions. Depending on the swimmers’ direction, split times were on average 0.16 s slower or faster in at least one lane at each of the 16 competitions, and in 49% of all lanes analysed. In 5 competitions, swimmers were shown to be faster in a majority of lanes in one direction as compared to the other. Analysis of the 50-m events at these 5 competitions indicate that preliminary performances were between 0.5 and 0.9% slower or faster than qualifying times, which is consistent with the direction effect observed in the distance freestyle events. Further, lane biases occur more often in temporary pools (70% of lanes) than in permanent pools (35% of lanes), with water currents as the most plausible cause. The prevalence of lane bias at elite-level swimming competition highlights the need for the implementation of policies and procedures to prevent such bias from occurring again in the future.