Here are some simple exercises that you can do to prevent shoulder pain and keep your shoulders mobile and strong.
1. Roll your shoulders in backwards circles. This is most easily done in the standing position with your arms down at your sides. Repeat 10 times.
2. Squeeze your shoulder blades backwards and together. Hold the position for 5-10 seconds. Repeat 5-10 times.
3. With your thumbs pointed upward, reach up in front of you until your arms are stretched overhead. Hold the position for 3 seconds. Repeat 3 times.
Be sure to do all of these in a slow and controlled way, in order to minimize risk for injury during the exercise. If you already do shoulder exercises, be sure to check your technique. I go to a gym regularly, and I often see people performing exercises incorrectly, which increases their risk for pain and injury. If you hurt yourself, you will limit your ability to work out in the future, so prevention is the key!