Things done in a deliberate, rhythmic way are measured. When you're walking toward a deer in the woods, trying not to scare it off, you'll take slow, measured steps.
When you meditate, you take measured breaths and pay attention to the inhale and exhale. And your measured strides up the side of a mountain trail will carry you more quickly to the top than short, erratic bursts of walking and stopping. Measured also means "thoughtful" or "careful," like the measured words you use in your delicately worded resignation letter.