Blkadr,
I know that to be true. I played football (soccer over here) for 30 years and I know that when I was on the field with some unexpressed emotion held in my body, my skills were compromised, nothing flowed right. I also recall that when I got on the field after clearing what was previously stuffed down, sometimes by crying a bit (gasp!), my game was fluid, faster, less effort and I scored many more goals.
Men who have the courage to let themselves cry usually experience life at a higher level because they haven't armored themselves against their own feelings, as well as others'. Similarly, being truly affected by music requires dropping one's guard and trusting that actually feeling something won't hurt you. Shutting down your emotions, whether in a relationship or listening to music, is the real cowardice.
And if that wasn't enough, women seem to seek masculine men who allow themselves to feel. What more would a man need to know?