Resistance is like driving with one foot down on the accelerator and the other foot down on the brakes: pretty soon the engine just burns out!
Trying harder (pushing the accelerator) only accelerates the burn-out. But releasing resistance (the brakes) unleashes the engine's true power.
Whenever you start feeling burned out, ask yourself, "In what ways am I pressing down on the brakes?"
For example, say you're trying really hard to prevent your child from getting upset, and it's exhausting you. Maybe you perceive your child's upsets as a personal failure, and you're putting the brakes on that. Releasing the brakes would mean deciding not to resist failing — telling yourself, "It's okay if I fail... It's not the end of the world."
Paradoxically, releasing your resistance to failure would free up the energy you need to succeed!