Assuming the work you're doing is worth while, burnout and stress are due to having (or perceiving to have) responsibility but insufficient power or authority to actually meet it. Working hard does not lead to burnout. Working hard but being unable to achieve expected results does. Taking time off rarely helps, because that impossible to meet responsibility is still hanging over you.

Classic example is school teachers in US public schools. They have enormous responsibility with the children, but rarely have power or authority. Instead, they are essentially drones in a big machine.