According to Professor Jeremy Bailenson, founding director of the Stanford Virtual Human Interaction Lab, there are several options to reduce online fatigue. He also explained why people generally feel more tired after meeting at Zoom.
First of all, when communicating via video communication, a person much more often than in real life looks at the screen, that is, as if in the eyes of the interlocutor, or at the camera. Therefore, you can not constantly look at the camera, but rather look away, as if thinking about something.
Also, at an online meeting, people often try to make their gestures and emotions more expressive so that the interlocutor understands them accurately. This is tiring too. The solution to this problem is to agree that when you are not performing, you will just listen with your webcam turned off.