Chapter Two, The Breath, discusses breathing, breath support, relaxation, air compression, blowing exercises, the diaphragm, the lungs, inhaling and exhaling air, circular breathing, the relaxed throat, the glottis, warm-up exercises and excessive tension.
Really low sagging, like practically with your pants at your kneecaps is not in style right now, but sagging to show a little underwear, or the more PC term low rise is still in. Sagging is purely a thug influenced thing, dudes do this look like wannabe thugs that lost their belts in prison. I won't even lie.
Pants worn this way are kept up by constant hitching, an act that becomes an integral part of the walking style of the wearer. While sagging did gain its start in the U.S. prison system, it was not a clothes-wearing style authored by imprisoned homosexuals intent upon advertising their interest in casual flings.