3 adjectives to describe robustness

These exercises added ten-fold robustness and vigour to his former qualifications.

Maurice, his first pupil, was a delicate and indolent child, and showed little robustness of character till his early manhood, when the necessity of a career forced him into the ranks of the great army.

She also had reached the autumn: she had the beaming smile and serene robustness of the valley.

3 adjectives to describe  robustness