Fitness is a multifaceted thing. When you have a shoulder injury, that is to say, you can't do push-ups and weightlifting, but you can do squats, waist exercises and running. Running around doing nothing is a very good way to keep fit. There is no great burden on your body and it is easier. After running for a while, your arm strength may decrease a little, but after your shoulders recover, it will be fine to train for a while, and the decrease will not be much, only a little.
You need a lot of training and intensive training to improve the strength of your shoulders and arms. But your shoulder is injured, you can't train with high load, and you don't want to waste the strength of your arms and shoulders when you recover. Shoulder recovery training can be carried out, and the shoulder load is small, which can promote shoulder recovery, such as scapula training and pendulum training, which can help you recover well. But it must be noted that if there is intense pain, you must stop training, because pain is the self-protection of the brain. If the pain is severe, it means that your shoulder has been hurt more, so when you feel severe pain, you must stop training.
Fitness is a very good move, but you must be careful not to overdo it. Once overdosed, it is easy to get hurt, and it takes a long time to recover after injury, which often delays the progress of fitness. Moreover, the years are very long. Once injured, you'd better rest and do some rehabilitation training. Even if you regress, because you have a certain foundation, it is easy to train later. Don't train with pain, it's easy to leave permanent injuries.