These two terms describe different aspects of breathing — one is a movement pattern, the other is a rhythmic structure. They are complementary.
Diaphragmatic breathing describes how the body moves during a breath — the diaphragm is the primary driver and the belly rises with the inhale. It is contrasted with chest breathing, which is more common in stressed or anxious states.
Box breathing describes the timing of the breath — four equal phases. It says nothing about how the body should move. In theory, you could do box breathing with either a diaphragmatic or a chest pattern.
In practice, box breathing done correctly tends to encourage diaphragmatic engagement — the slow count gives the breath time to move into the lower lungs. Combining both — a belly-led 4-4-4-4 breath — is generally considered the most effective form of the practice.
Practice box breathing with guided sessions, streaks, and relaxing music.
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