When a couple having more sex, it will create a good health for both. However, if they masterbate, it's not good for health, as masterbating prevent them from exercise because one just lay down and masterbate in the bed.
Don't be shy to talk about sex. It's amazing for our human life. It's also good talk about it with your teenage kids to learn how to have sex and prevent them from disease. Sex is not something impolite or something bad, but it's something life give to us, so enjoy with it. But you should learn how to do with it to feel good and safe.
You can have sex often if you can to rate your heart beat. It's very good for health.