In which range is the normal heart rate of people around 20 years old? Does hot weather affect heart rate?

The resting heart rate of normal adults has significant individual differences, with an average of about 75 beats/min (between 60- 100 beats/min). Among adults, women's heart rate is generally slightly faster than that of men. The same person's heart rate slows down when he is quiet or sleeping, and increases when he is exercising or excited. Under the influence of some drugs or neurohumoral factors, his heart rate will increase. People who often engage in manual labor and physical exercise usually have a slow heart rate.