脉跳

例句：

1. 1. He was having a hard time keeping his heart rate down.
   他很难控制自己的心率。
2. 2. The doctor checked her pulse to make sure she wasn't having a heart attack.
   医生检查了她的脉搏，确保她没有心脏病发作。
3. 3. During the race, he kept his pace steady and controlled his pulse.
   比赛中，他保持了稳定的速度，控制了他的脉搏。