So many myths and mistruths caught up in 2 simple questions. I'll attempt to tackle this one question at a time.
Many people will contend that heavy compound lifting is the only core exercise that some need (I sort of agree with this). Most core "isolation" is pointless, and mostly recruits the hip flexors anyhow. So, as long as bodybuilders continue to train with compound lifts, then yes, they are training their midsection.Is it true that bodybuilders do not really train the mid section since they want a tight small waist look ?
It is true that heavy squats and dead lifts will make your core stronger. These lifts require isometric contractions of the core in order to stabilize the load. If you were to rely on isometric contractions for hypertrophy in the rest of your body, you'd be pretty small.Also is it true that real heavy lifts like Squats and Dead lifts increase your waist size ?
Now, Poundstone has an interesting theory that people who rely on belts suffer greater distention because of always pushing your abs out against the belt. This is just a theory.. it makes sense, but there is more to it than that. Read this article from Kovacian to get more insight.
The Kovacian: Why Bodybuilders Get Distended Stomachs & How to Prevent It! - RX Muscle Mag