The antonyms for the word "being recumbent" would be active, upright, erect, standing, and vertical. These words describe a completely opposite position to being recumbent or lying down. Someone who is active is involved in physical activity or engaging in something, while someone who is upright is sitting or standing straight. If someone is erect, they are standing up straight with their shoulders back. Similarly, someone who is standing is on their feet, while someone who is vertical is also up straight. These antonyms illustrate that there are many different ways to describe someone's physical position or level of activity.