the fastest time, highest score, best result, etc. that a particular person has ever achieved in a sporting event

Hayley won the silver medal, cutting almost 11 seconds off her personal best. 海莉获得银牌，比她之前的个人最好成绩缩短了近11秒。

She finished with personal bests in six out of the seven events. 她在7个项目中的6个都取得了个人最好成绩。