I am not certain I remember this correctly, but I think one of the Krauss papers stated that LDL pattern A (larger articles, and more health positive) can be converted to the negative small partile pattern B by a low fat, high carb diet. But it may be th tdiet tends not to change a person from negative pattern B to better pattern A.
Regarding exercise specifically, a paper by a different Dr. Kraus (William E Kraus, not Donald M Krauss), showed that at 3 hours of aerobic exercise (usually 3 one hour sessions) did increase average HDL significantly over and above the controls. The participants jogged or rode exercycles at 65-80% of maximum heart rate.
Ha