Data from elite professional sports players provide a valuable source of information on human performance and ageing. Functional declines in performance have been investigated across a wide range of sporting disciplines that vary in their need for physical strength, endurance, cognitive ability and motor skills, but researchers do not always consider other sources of heterogeneity that can exist between individuals. Using information on all male bowlers to have played Test match cricket since the early 1970s, this study separated age-dependent variation in bowling performance at the population-level into within-individual and between-individual (age-class) changes. There was little evidence for senescence in bowling performance as measured via economy rate or wicket-taking ability, irrespective of the style of the bowler (fast or slow). Instead, analyses detected strong between-individual contributions to bowling performance as higher quality bowlers were able to compete at the elite level for longer, and were therefore over-represented in older age classes: how they accomplish this alongside the physical demands of Test cricket remains unresolved. Bowlers also experienced a deterioration in the last year of their Test careers. Lastly, multivariate models identified a negative correlation between slow bowlers in their economy rate and their wicket-taking ability, suggesting that in general, the most economical slow bowlers in the modern era of Test match cricket have also taken wickets at the fastest rate. The same is not true for fast bowlers, which is perhaps partly because bowling at high speed compromises accuracy and thus increases scoring opportunities for batters.

来自精英职业体育选手的数据提供了有关人类表现和年龄的有价值的信息来源。在各种体育学科中，由于对身体力量，耐力，认知能力和运动技能的需求而异，因此对功能下降的情况进行了研究，但研究人员并不总是考虑个体之间可能存在的其他异质性来源。该研究利用自1970年代初以来所有男子保龄球手打板球的信息，将人口水平上保龄球表现的年龄相关性差异分为个人内部和个人之间（年龄组）的变化。很少有证据表明，通过保龄球的风格（快速或慢速）可以通过经济性或检举能力来衡量保龄球性能的下降。反而，分析发现，保龄球运动员在个人之间对保龄球性能的贡献很大，因为更高质量的保龄球运动员能够在精英水平上竞争更长的时间，因此在老年年龄组中的比例过高：如何解决这些问题以及测试板球的身体要求尚待解决。保龄球运动员在职业生涯的最后一年也经历了恶化。最后，多变量模型确定了慢速保龄球运动员的经济率与检球能力之间的负相关关系，这表明，总体而言，现代的测试赛板球时代最经济的慢速球手也以最快的速度射门。对于快速投球手而言并非如此，这可能部分是因为高速打保龄球会降低准确性，从而增加击球手的得分机会。