Adherence

Increasing training frequency from 2x/week to 3x/week increases muscle hypertrophy but not maximal dynamic strength, regardless of muscle typology.

If your goal is to build muscle, training 3 times a week is likely more effective than 2 times a week, even if you only add one extra session. This benefit applies to everyone, regardless of their muscle fiber type. However, this extra frequency may not translate to greater strength gains, so prioritize hypertrophy if that is your goal.