The Diamond of Support is a killer exercise from Janice Chapman in her book Singing and Teaching Singing. It neatly explains in an easy-to-use exercise how the abdomen should be working in order to keep the voice healthy and strong. It also neatly cuts out tension from the rectus abdominis, a nasty centre for laryngeal tension. It's a great exercise - and here presented by Matt Pocock.
Singers who suffer from lots of bodily tension, who've been told that they tend to 'shout' the words, should really pay attention to the feeling of release in the centre of the body. Best of luck!