In the reverse, the man with a larger frame and more solid build should increase by 10%, to roughly  (BMI 23.7). If one teeters on the edge of small/medium or medium/large, common sense should be used in calculating one's ideal weight.
Conversely, a man with a bigger frame and stronger build should increase his weight by 10%, reaching roughly (BMI 23.7). If someone is between small/medium and medium/large sizes, using common sense is important to determine their ideal weight.