Generally speaking, the interval of strength training should be 1-3 minutes. Specifically, if it is a big weight to stimulate muscles, if it is done by a group, it needs a big interval of 3 minutes. Such a long interval can effectively adjust the muscles and make the next group's heavy weight better. However, at present, the training method of stimulating muscles with heavy weight is not advocated, because it will cause great pressure on joints and damage the body due to its own or external factors, and the risk factor is relatively high. Personal fitness concept is: moderate weight, large groups, large times and small intervals to stimulate muscles and stimulate muscle expansion, so as to achieve the effect of muscle gain. What is medium weight? 120%- 140% of the warm-up weight is medium weight. For example, a 50KG warm-up, with a medium weight of 60KG-70KG (the specific weight can also be selected according to your own situation), the number of single action groups in this strength training is more than 4 groups, each group 12 times or more, and the interval is less than 2 minutes (recommended 1 minute interval). There is an old saying that "light muscles practice heavy muscles", which means that the best way to grow muscles is to stimulate them with a very light weight. Using the above methods can not only stimulate muscle growth, but also exercise good muscle lines, killing two birds with one stone. Emphasis is placed on raising the limit of strength and improving one's absolute strength, that is, increasing strength. As for the interval you mentioned, in the end, it depends on whether you choose the purpose of strength training, whether you want to grow muscles quickly or increase strength, and then choose the interval in combination with your own factors. Fitness should have a goal and achieve it. Choosing the right training method is the key. Your suggestions can be used for reference, and your own experience can be applied to training, which really suits you! I hope my suggestion can help you a little.