Sucking it in puts a lot of stress on your lower back… i wouldn’t advise doing that.
No it doesn’t gouda. “Sucking it in” is a good exercise.
Running will work your cardio.
Walking is by far the best way to burn body fat, as body builders have known for years (a bodybuilder that goes to my gym, 6 weeks before a big contest he gets out and walks for 2 hours a day, drinking a shitload of water and downing protein shakes).
Although you dont need the protein shakes, walk, walk, and walk some more, while keeping a good diet will definitly shed those kilos very quickly.
And FYI, Pilates has any number of exercises that focus specifically on the deep abdominals. Since I started Pilates, I don’t think I’ve lost any weight, but I look a bit thinner since my deep abdominals are in better shape and are holding my trunk in a better position.
Whoops, missed this point when I was writing my earlier post. IANA Pilates instructor, but IME there are a couple of potential causes for this pain:
[ul]
[li]One of the deep abs (I forget which one) anchors in your lower back. If this muscle is weak, it can hurt (like any weak muscle can) when you work it.[/li][li]Sucking it in can stretch your lower back if it’s used to having an excess inward curve. This stretch can hurt a lot.[/li][/ul]
In any case, using proper form and keeping at it should alleviate the problems. Since I started doing Pilates, my back actually hurts a lot less than it used to.
(Insert standard disclaimer about seeing a doctor before beginning an exercise regimen, etc.)