If you have bursitis on your elbow or your knee, change the activity that caused it -- such as leaning on your elbows while reading or crawling on your knees in the garden.
If you enjoy throwing long in the pick-up football game at the park, consider handing the ball off to your trusted running back or tossing a shorter pass to the tight end. Sure, you have some comfortable habits, but they're not altogether necessary.
You can read sitting up in a different position. You can place a padded mat in the area you're gardening or simply sit sideways next to the flower bed. Adaptation is the key.