I’ve been doing this for fun (and rest) since I was 12 in swim team. I enjoy the feeling of controlling whether I float or sink, and launching off the bottom is

I’ve been doing this for fun (and rest) since I was 12 in swim team. I enjoy the feeling of controlling whether I float or sink, and launching off the bottom is less strenuous than treading water. I had no idea it was a Navy standard procedure.