Some people are stiff. Some are on the other end of that spectrum and require work to reach higher joint stability.
The work is easy but consistency is required to achieve success.
Here is an example for loose shoulders:
Place yourself in a push up position, you can begin against a wall and work your way to the ground.
Now, with your breathing as rhythm, Tense and relax one shoulder and then the next for sixty breaths.
Continue, by pulling the arms together and pulling them apart to the sides. Inward with the inhale and outward with the exhale. Repeat for sixty breaths.
Continue, by pulling the arms up and down and switching the direction between the sides. Inhale one way and exhale with the exhale. Repeat for sixty breaths.
Continue, by bending the arms at the elbows to half the height of the push up and repeating the process and then hovering a feather width above the surface.
For added, dynamic stability, follow the same process while facing away from the wall or by holding a stick in different angles. More on that, in my online mobility classes.
Do this twice to three times a week and you will see the results soon.