Research has shown that training a particular muscle results in increased levels of blood flow and lipolysis in the area (the breakdown of fat cells into energy you can use), however the difference it makes does not warrant it for reasoning to train abs frequently.
In an ideal world you would enter the gym with your set program, you would then swan around the gym switching from dumbbells to racks to machines, get all sweaty, leave and continue with your day. Seriously though, when does this ever happen?
Being too fat is a continuum or a scale where morbid obesity is at one end, and being completely ripped lean is at the other. This is not something new, it's just a different perspective. You could have a 60kg lean body mass consisting of muscle, bone, and organs, which, is either covered by 4kg of body fat, and you'd be classed as shredded, or, be covered by 40kg of body fat and be classed as obese. Losing body fat is often peoples main goal, and as you start to get leaner you move along the continuum from obese to ripped.
What I mean by this is, if your training program is progressive, and hits most major body parts frequently enough, it will do the job. The real reason you're not seeing progress is that you just don't train hard enough. You are not stressing your muscles enough to 'need' to grow.
Most people tend to cheat and swing through the back and shoulders in order to move too much weight, and by doing so, you fail to engage the arms fully. Take your time in each rep, use a full range of movement and finish each lift by contracting hard against the weight at the peak of your lift. Try to avoid your arms losing tension at either the top or bottom range.
How can we stop this craziness and go back to squatting 200kg for reps I hear you ask... Simple sit less! ha ha, well not so stupid... but, there are also a few things that can help get you back to having a healthy spine.
Maybe this explains why you've not been losing weight when you've been so damn good most of the week. Don't worry, you're not the only one. It's just that most of us have no idea how many calories are in the things we eat, even the innocuous ones like dips and sauces.
In order to function as animals we must consume some protein. Proteins literally are the building blocks needed for all physical parts of our bodies. This ranges from skin, hair, nails, nerves, enzymes, antibodies, blood, muscle....everything.
As you can see there is nothing glamorous about getting super lean, it isn't even that complicated and I promise this is what I actually do and what my clients will do. It is all about your start point, pure determination, and consistency.
This would not be one of my articles if there weren't a few brutal home truths before I get into the nuts and bolts of how to do it. I can speak honestly on this as I am a seasoned natural bodybuilder and I know what is needed to get shredded.