Motion IS Lotion. I stole this saying from one of my favorite doctors in Tallahassee. When you move, your body creates more synovial fluid in the joints. This is what lubricates the joints and keeps them free from injury and pain.
Any kind of "safe" motion is good. Movement also makes your blood flow through your body more and this creates an all over healing. If you have any aches and pains, a lot of times you can ease them just by bringing blood and warmth to the area.
Also, if you are sore from a previous workout, running or carrying babies around, you can push the lactic acid (this is what gathers in the muscles when you create a sore muscle) out by moving more. Most people who get stiff and sore, don't want to do anything, but if you moved more while you are sore, you would be LESS sore.
This is John. He is one of my lovely clients. He is 88 years old. He doesn't need a strenuous workout. So we split the workout between simple, standing, balance moves and a chair workout. He is about to do a chair move that creates blood flow through his whole body while still sitting in the chair. He will take the weights, that my lovely and precious assistant is handing him, and lift one hand above his head while he lifts the opposite knee. He will then alternate, in kind of a marching motion. This works out his arms, core and legs.
If you are more advanced (in physical ability not age!) you can do this move standing. Try to kick your leg straight out in front of you while you lift the opposite arm. Remember to pull your stomach muscles in and try not bend forward. Use 5-8 lbs. weight in each hand (could be a can of soup or bag of rice). You will be getting a full body workout, which creates the most blood flow.
These are only a couple of suggestions. Like I said, any "safe" motion is good. Motion is Lotion!