Licensed plumbers are required by code to install water saver shower heads and faucets that introduce a high volume of air into the water stream, which is why it takes four days to fill a large coffee pot, but homeowners are allowed to do whatever they want to the shower head after it has been inspected (if an inspection is needed- such as new or remodel construction). You might find you can actually soothe achy muscles and spend less time in the shower because you can get the soap rinsed out of your hair!