I really improved my abdominals while driving, simply by holding my gut in as far as I can, (go easy
on this the first day - if you try it yourself).
Of course, anyone can make their abs look better in 2 seconds simply by holding them in; I'm
talking about the long term effect over weeks or longer.
Anyway, most people drive their vehicles at least 30 minutes a day, and driving is a pretty low
concentration activity, so all that freeway time should make getting the ol' midsection to look better
easier. Also, if I have something to do which requires lots of back stress, holding the gut tight
takes a tremendous load off my back. (For example, I'm currently deadlifting 350 to 425, assuming
I've warmed up well, etc.). Not bad for a 62 year old body.
Of course, in addition to this "driving ab technique", I find it necessary to work out pretty
intensely 5 days a week for about 1 hour and 25 minutes to achieve a reasonable level of fitness and
strength. Lots of body weight exercises - push ups, pullups, sit ups, free weights, etc., are the way to go.
The other idea which helps my whole body (abdominals especially), tremendously is chewing my food
really well - roll it around in my mouth, try to coat it with saliva as you're chewing it. In this fast and faster society, we tend to forget such things.