निषेधनं प्रपञ्चस्य रेचकाख्यः समीरणः ।ब्रह्मैवास्मीति या वृत्तिः पूरको वायुरीरितः ॥ ११९ ॥
In plain words
Negating the whole spread of the world — that is the out-breath, recaka. The one thought, 'I am Brahman alone' — that is declared to be the in-breath, pūraka.
Close to the Sanskrit
The negation of the manifold world is the breath called recaka; the mental modification which is 'I am Brahman alone' is declared to be the pūraka breath.