I've done a lot of breathing exercises due to freediving. I think the main benefit for me was that it's almost like meditating. While lying there and breathing

I've done a lot of breathing exercises due to freediving. I think the main benefit for me was that it's almost like meditating. While lying there and breathing up or holding my breath, my mind is completely clear. No thoughts, just staying as relaxed as possible focusing on my diaphragm. No scrolling on my phone thinking about my day, nothing. Just relaxing. Except the last minutes when the body screams at you to breathe because of the co2 buildup, heh. But not sure if there's anything more to it than that? I don't do it as often anymore, but get the same focus from working out.