connected with running a race over a distance that is neither very short nor very long （赛跑）中距离的 a middle-distance runner (= for example, somebody who runs 800 or 1500 metre races) 中距离赛跑选手（如 800 米或 1 500 米跑选手）
Oxford Collocations DictionaryMiddle-distance is used with these nouns:- event
- runner
- running
- …