RM is the abbreviation of "repetition maximum" in English, which is translated into "maximum repetition value" in Chinese. It is the highest number of repetitions of a certain exercise that the practitioner can do under a certain weight, and it is the RM of this action and this weight.
The reason why the concept of RM appears is because it is found through research that it is not effective to practice until exhaustion every time. The choice of weight and times (and the number of groups) has a great influence on the training results.
Extended data:
The relationship between RM selection and training effect;
1 and 1-4RM mainly train absolute muscle strength and volume.
2, 6- 12RM is mainly for training muscle mass.
3. 15-20RM is mainly used to train small muscle groups and enhance muscle lines and elasticity.
4, 30RM and above mainly play a role in reducing body fat and enhancing cardiopulmonary function.
Baidu encyclopedia -rm