Abstract: We started from the definition of HIT,and the historical development of HIT,and reviewed the relative literatures on HIT with different populations.We define HIT as a training method,which consists of multiple efforts with intensity of≥ anaerobic threshold or maximal lactate steady state and with durations from seconds to minutes,and is interspersed with rest or low-intensity exercise between each two efforts.As indicated by the literatures,the training effect of HIT is different on different training populations.Although HIT may be a time-efficient and effective training/exercise method for the non-elite athletes and the public populations,the effect of HIT on elite athletes is still open for research.As for the people with health disorders,HIT could be preferred progressively if the safety is guaranteed.Further investigations,especially with elite athletes,are required in the future to know the mechanism of HIT in enhancing the exercise capacity.