Physical activity ( non-contact sports ) is usually okay to continue when you get a new tattoo as long as you take extra good care of it. If you get sweaty, take a shower and clean it as soon as you can. If you're a body builder, just avoid lifting weights with that particular muscle for a few days so you don't stretch it too much. Keep it covered if it has to come in contact with any tight clothing that may rub during movement. Remove any covering as soon as your workout is completed. Contact sports like football and wrestling are much more potentially damaging for a new tattoo. In this case a tattoo would really not be a wise choice unless it was possible to avoid the sport for at least a couple of weeks.
You can decrease the risk of infection if you follow the home treatment steps for cleaning and caring for a wound. Prompt treatment of an infection can prevent more serious problems. If you have any signs of infection it is recommended to consult your tattoo artist before going to the doctor. Most tattoo artist have been trained to know the signs of infection. If the artist has confirmed you do have an infection, you will contact your doctor as they will be able to diagnose the infection and give you the proper tools for treatment.