जो संयम से रहता हो।

संयमी व्यक्ति कभी बीमार नहीं पड़ता।
परहेजगार, परहेज़गार, परहेज़ी, परहेजी, संयमशील, संयमी

In full control of your faculties.

The witness remained collected throughout the cross-examination.
Perfectly poised and sure of himself.
More self-contained and more dependable than many of the early frontiersmen.
Strong and self-possessed in the face of trouble.
collected, equanimous, poised, self-collected, self-contained, self-possessed