(06) OPTIMIZING BODYWEIGHT CATEGORIES FOR USE IN PARA POWERLIFTING COMPETITIONS TO IMPROVE ‘FAIRNESS’

Background: Bodyweight categories (BCs) are used in many sports to ensure competitive fairness. This is especially true in strength sports such as powerlifting. However, in Para Powerlifting it is unclear if the current BCs used by the World Para Powerlifting organization are optimal.

Purpose: This investigation sought to analyse and refine Para Powerlifting BCs while retaining the same number of overall BCs (n=10) for each sex. The key defining principles of refined BCs were a more even distribution the athlete pool and minimization of any impacts of body weight on performance.

Methods: Retrospective competition records from 2013 onwards comprising a total of n=2,012 athletes (senior elite males = 1177, senior elite females = 577, junior males = 198, and junior females = 60) competing in World Para Powerlifting sanctioned competitions were collated and used for analyses. An evolutionary strategy, with a specific ‘fitness function’ and grandchild schemes was employed independently for elite senior male and females to develop new optimized BCs. Chi-squared (χ²) goodness of fit tests were used to determine distribution of the athlete pool across current and optimized BCs for each sex. Spearman’s rank correlations determined if performance was related to bodyweight. These optimized BCs were also tested against junior athletes to determine suitability, again using Chi-squared goodness of fit tests for each sex. For all tests significance was set at p< 0.01.

Results: Optimized BCs (males: < 50.5kg, < 57kg, < 62.5kg, < 68kg, < 72kg, < 79kg, < 86kg, < 94.5kg, < 105kg and >105kg), and (females: < 42kg, < 46.5kg, < 51kg, < 54.5kg, < 60kg, < 65.5kg,< 71.5kg, < 77.5kg, < 85kg, and >85kg) differ from those currently used (males: < 49kg, < 54kg, < 59kg, < 65kg, < 72kg, < 80kg, < 88kg, < 97kg, < 107kg and >107kg) and (females: < 41kg, < 45kg, < 50kg, < 55kg, < 61kg, < 67kg, < 73kg, < 79kg, < 86kg, and >86kg). The optimized BCs allow better distribution of the athlete pool (χ² of p >0.01 for both males and females indicated an even distribution) and fewer BCs with a significant bodyweight-performance correlation (4 in current versus 1 in optimized scheme across sexes). However, neither the current nor optimized BCs enable an even distribution of the junior athlete pool (χ² of p >0.01).

Conclusions: Optimized Para Powerlifting BCs may improve the distribution of the elite senior male and female athlete pool with less of an impact of bodyweight on performance. However, the senior elite BCs (both current and optimized) are not suitable for junior athletes likely due to physical immaturity resulting in lower junior athlete bodyweights. PRACTICAL APPLICATIONS: Sports using athlete bodyweight, or other classification methods, should closely consider the efficacy of categorization methods in use. We suggest an analytical approach is adopted in such sports to ensure competitive fairness.

Acknowledgements: None